Why do I keep getting pimples on my butt?

No study tracked a general group of people to see how often buttock pimples come back. But friction from tight clothing or sitting, sweating, and obesity were each linked to more frequent outbreaks in small studies, and bumps that keep returning in the same spot can be a sign of hidradenitis suppurativa rather than ordinary pimples.

Why do I have so many pimples on my butt?

Studies found folliculitis was far more common in children with obesity than in normal-weight children, and heavy sweating or friction (seen in sailors after weeks at sea) was linked to more outbreaks. No study set a number for what counts as 'too many.'

Can you get a pimple in your butt crack?

Yes. Studies describe the fold between the buttocks (the gluteal cleft) as a site for folliculitis, hidradenitis suppurativa, and pilonidal disease, a separate condition involving hair and cysts near the tailbone.

Should I stop treating it like facial acne?

If scrubs or spot treatments aren't helping after a few weeks, stop and see a doctor rather than continuing them. These studies suggest persistent or painful bumps in this area are sometimes a different condition, hidradenitis suppurativa, that doesn't respond to acne treatment and may need antibiotics, biologics, or surgery instead.

Why do I get pimples on my butt?

Name: Why do I get pimples on my butt?
Published: 2026-10-13
Keywords: why do i get pimples on my butt, why do i keep getting pimples on my butt, why do i have so many pimples on my butt, can you get a pimple in your butt crack

In adolescents and adults who develop recurrent pimple-like bumps on the buttocks or gluteal cleft, what proportion are due to folliculitis versus other causes such as acne mechanica, hidradenitis suppurativa, or keratosis pilaris, and how do these conditions differ in clinical course and response to treatment?

How people search for this, in their own words

“why do i get pimples on my butt”
“why do i keep getting pimples on my butt”
“why do i have so many pimples on my butt”
“can you get a pimple in your butt crack”

Evidence review in plain language · compiled 2026-10-13 · checked 2026-10-13 · next 2026-11-13 · automated review, how it works

Bottom line

No study has measured what share of buttock bumps are ordinary folliculitis versus other causes — almost all the research found instead describes hidradenitis suppurativa, a distinct, more severe chronic condition, studied only in people already diagnosed with it.

The certainty here is very low. The only study to directly examine non-pilonidal causes of gluteal-area bumps was a single 21-patient case series, which found ordinary folliculitis alongside several unrelated diagnoses. One study of competitive sailors found more buttock folliculitis after weeks of friction from racing gear, and small case reports describe hidradenitis suppurativa flaring at sites of mechanical friction from a hernia belt or a bra strap. In people already diagnosed with hidradenitis suppurativa, obesity has been linked to higher rates of folliculitis in children, and long-standing, severe buttock lesions have in some reported cases been linked to skin cancer and, in one small study, to lower sperm quality — but none of this tells you how common ordinary folliculitis is compared with other causes, and no trial has compared any treatment for common buttock folliculitis against doing nothing.

How certain

Very low

The only direct evidence is 1 small or uncontrolled study.

What it shows

Signal of harm

11 studies reported harm or tissue damage, including laboratory evidence.

studies found: 120studies found
randomised trials: 0randomised trials
people studied: 119,336people studied
reviews of trials: 6reviews of trials
years covered: 2012–2026years covered

Read this first

Long-standing, untreated hidradenitis suppurativa in the buttock area has, in reported cases, progressed to a type of skin cancer (squamous cell carcinoma), sometimes fatal.
Men with severe hidradenitis suppurativa affecting the buttocks and genitals had worse sperm quality and a high rate of erectile dysfunction in one small study.
Friction from tight clothing, bra straps, or prolonged sweating (as in sailors on a long voyage) was linked to new or worsening boil-like bumps in case reports.
Obesity was linked to significantly more folliculitis in children in one study.

What the research shows

Proportion of buttock pimples due to folliculitis vs other causes (acne mechanica, hidradenitis suppurativa, keratosis pilaris)
No study surveyed a general group of people with buttock pimples and sorted out how many had each cause. The closest study looked at 21 adolescents already referred to a specialist pilonidal clinic, which is not a general population.[1]
Not studied
Clinical features that tell the causes apart (location, tenderness, recurrence pattern)
Some studies describe patterns — tunnels and blackhead-like openings point toward hidradenitis suppurativa, fistulas and ulcers point toward bowel-disease-related lesions — but these come from people already diagnosed with a specific severe disease, not people trying to work out what their bumps are.[1,2,3]
Insufficient evidence
Response of keratosis pilaris (rough small bumps) to topical treatment
A survey of dermatologists found lactic acid and salicylic acid creams were the most commonly used and generally felt to help, though bumps often returned within three months of stopping. A registered trial comparing treatments has not yet reported results.[1,2]
Possible improvement
Resolution with topical or oral antimicrobial treatment
No trial tested antibiotics against a placebo for ordinary buttock folliculitis. The only antibiotic-related findings come from hidradenitis suppurativa cohorts, a different and more severe disease, where antibiotics were described as helpful but not tested in a controlled way.[1,2]
Insufficient evidence
Recurrence rate over 6 to 12 months
No study followed a general group of people with buttock pimples for 6-12 months to track recurrence. Recurrence figures that do exist come from surgery for severe, longstanding hidradenitis suppurativa, which is not the same as ordinary pimples.[1,2,3]
Not studied
Link to friction, sweating, or occlusive clothing
Sailors developed more buttock folliculitis after three weeks at sea, a man developed boil-like lesions exactly where a hernia and tight trousers rubbed, and a woman developed boils where her bra strap pressed. These point to friction and moisture as triggers.[1,2,3]
Possible harm
Link to obesity and other health conditions
Children with obesity had folliculitis far more often than normal-weight children, and children with Down syndrome had much higher rates of recurrent folliculitis, most often on the buttocks.[1,2]
Possible harm
Whether persistent bumps could signal a more serious condition needing medical care
Case reports and chart reviews describe long-standing, untreated hidradenitis suppurativa in the buttock area turning into skin cancer, and severe buttock/genital disease being linked to lower sperm quality and erectile difficulty in men. These harms were seen in diagnosed, severe, long-term cases, not typical mild pimples.[1,2,3,4,5,6]
Possible harm

What it may help with

For keratosis pilaris specifically, a survey of dermatologists found lactic acid and salicylic acid creams were the most commonly used treatments and were generally considered helpful, though bumps often returned within three months of stopping treatment.[1]

Important limitations

None of the 120 studies found is a randomised trial, so none can prove what causes buttock pimples or fairly test one treatment against another.[1,2,3]
Most of the studies found are about hidradenitis suppurativa — a chronic, progressive skin disease affecting an estimated 1-4% of people, with painful nodules that recur, rupture and drain, often in the armpits, groin and buttocks — rather than about simple, occasional pimples in that area.[1,2,3]
Most participants were already diagnosed with hidradenitis suppurativa at specialist clinics, so these studies cannot say what share of 'buttock pimples' in the general population are folliculitis, keratosis pilaris, or something else.[1,2,3]
A large share of the evidence is single-patient case reports, which describe one person's experience and cannot show how common any cause, treatment response, or harm actually is.[1,2,3,4]

What the studies found

Found a benefit34 · 28%
Found no clear effect1 · 1%
Mixed or unclear74 · 62%
Found possible harm11 · 9%

What kind of studies

Case series44 · 37%
Retrospective27 · 23%
Narrative review24 · 20%
Case-control7 · 6%
Prospective cohort4 · 3%
Meta-analysis3 · 3%
Systematic review3 · 3%
Registry3 · 3%
Guideline2 · 2%
Laboratory study2 · 2%
Registered trial, no results posted1 · 1%

The studies that decided it

Emengo et al. 2025
Adolescent Gluteal Cleft Pathologies Not Due to Pilonidal Disease: A Case Series and Diagnostic Algorithm
Butt bumps can have many causes.Case seriesLow qualityRelated question
21 people2025
21 patients had non-pilonidal diagnoses including neurological conditions, skin diseases like folliculitis, inflammatory bowel disease, sacral dimples, and a pressure ulcer; researchers built an algorithm to distinguish these from pilonidal disease
Who was studied
adolescent patients with gluteal cleft problems seen at a pediatric pilonidal clinic
What they received
diagnostic work-up for non-pilonidal causes of gluteal cleft symptoms
Compared with
none (descriptive case series)
Main outcome
final diagnosis causing gluteal cleft symptoms other than pilonidal disease
Quality
This is a small retrospective case series without a comparison group, so it can describe possible causes but not prove how common any one cause is.
Limitations
Retrospective review; small number of patients; no comparator group; focused on a specialty pilonidal clinic population, which may not reflect general cases of buttock pimples.
Taken word for word from the abstract
- n We identified 21 patients who had diagnoses other than pilonidal disease
- population We performed a retrospective review of all patients who presented to our pediatric Pilonidal Clinic from 1/2019 to 12/2023.
- intervention Patients who received a work-up for diseases separate from pilonidal disease were included in our study.
- comparator We reported a series of adolescent patients with non-pilonidal gluteal cleft pathologies.
- primaryOutcome Patient demographics, clinical work-up, and treatment outcomes were recorded.
- result 4 patients had neurological diseases (schwannoma, central disk protrusion, arachnoid cyst, Tarlov cyst); 7 patients had dermatological diseases (folliculitis, moisture-associated skin damage); 5 patients had inflammatory bowel disease; 4 patients had sacral dimples; and 1 patient had a sacral pressure ulcer.
Clin Med Insights Pediatr · PMID 40861268 · Read it on PubMed ↗
Lotan et al. 2023
Association between Hidradenitis Suppurativa and Abnormalities in Semen Parameters and Sexual Function: A Pilot Study
Worse sperm quality, erectile dysfunction.Case-controlLow qualityRelated question
72 people2023
men with severe buttock/genital lesions had worse sperm quality than those without such lesions or healthy controls, and 93% reported erectile dysfunction
Who was studied
men with hidradenitis suppurativa (a chronic skin condition), compared to healthy men
What they received
having hidradenitis suppurativa, including some with lesions on the buttocks and genitals
Compared with
healthy men who were spouses of infertile women undergoing IVF
Main outcome
sperm quality, hormone levels, testicular ultrasound, and erectile function
Quality
this was a small pilot study comparing patients to controls who were not perfectly matched, so it cannot prove HS causes these problems.
Limitations
small pilot study; patients with HS were younger and more often smokers than controls; controls were drawn from an infertility clinic, not the general population
Taken word for word from the abstract
- n 28 men attending a tertiary HS clinic during the period April 2019 to April 2021, and 44 healthy controls
- population Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease affecting patients of reproductive age
- intervention Patients with HS were divided based on the absence or presence of gluteal and genital lesions
- comparator 44 healthy controls, spouses of infertile women undergoing semen evaluation before in vitro fertilization
- primaryOutcome findings on semen and hormonal analysis, testicular ultrasound, and the International Index of Erectile Function (IIEF-15)
- result Semen parameters in patients with gluteal-genital lesions, specifically those with severe scrotal involvement necessitating surgery, were lower than the WHO reference values and significantly lower than in patients without gluteal-genital lesions and controls. Erectile dysfunction was reported by 93% of patients with HS.
Acta Derm Venereol · PMID 37974484 · Read it on PubMed ↗
Güven et al. 2022
Cutaneous manifestations of obesity in Turkish children: A comparative study
More skin bumps if obese.Case-controlLow qualityRelated question
168 people2022
Folliculitis was significantly more common in obese children than in normal-weight children (31.7% vs 5.8%)
Who was studied
Turkish children, comparing those with obesity to normal-weight children
What they received
having obesity
Compared with
normal-weight children
Main outcome
presence of various skin conditions, including folliculitis (a cause of pimple-like bumps)
Quality
This is a single cross-sectional comparison in children, so it can show an association with obesity but not prove obesity causes the skin bumps, and it does not specifically study buttock pimples in the general population.
Limitations
Cross-sectional design with no follow-up, no treatment tested, and findings are about multiple skin conditions in obese vs normal-weight children rather than specifically about buttock pimples in a general population.
Taken word for word from the abstract
- n 82 children with obesity and 86 normal-weight healthy control children were enrolled
- population 82 children with obesity and 86 normal-weight healthy control children were enrolled
- intervention children with obesity
- comparator normal-weight healthy control children
- primaryOutcome We aimed to determine the prevalence of skin manifestations in children with obesity by comparing them to normal-weight children.
- result folliculitis (31.7% vs. 5.8%, p < .001)
Pediatr Dermatol · PMID 35285075 · Read it on PubMed ↗
Sachdeva et al. 2021
Squamous cell carcinoma arising within hidradenitis suppurativa: a literature review
Rare skin cancer in long-term HS.Systematic reviewVery low qualityRelated question
95 people2021
Nearly half of the skin cancers occurred in the buttock area, and most patients who developed this cancer had high rates of spread or death
Who was studied
people with longstanding hidradenitis suppurativa lesions
What they received
having chronic hidradenitis suppurativa lesions (no treatment studied)
Main outcome
development of squamous cell carcinoma (skin cancer) within HS lesions, and related metastasis, recurrence, and death
Quality
This is a review of scattered past case reports without a control group, so it can't reliably show cause and effect.
Limitations
Based on pooled case reports with incomplete outcome reporting; no control group or statistical pooling across studies.
Taken word for word from the abstract
- population Of the 95 patients (mean age: 52.9 years) who developed a total of 122 SCCs within HS lesions, the majority were males (77.9%, n = 74/95).
- intervention SCC development in pre-existing HS lesions
- primaryOutcome characteristics and outcomes of SCC development within HS lesions
- result The most common sites of SCC were the gluteal region (47.5%, n = 58/122), the perianal region (18.9%, n = 23/122), and the genitals (13.9%, n = 17/122).
- result 58.7% (n = 44/75) experienced a mortality outcome
- n Of the 95 patients (mean age: 52.9 years) who developed a total of 122 SCCs within HS lesions
Int J Dermatol · PMID 34075588 · Read it on PubMed ↗
Sechi et al. 2019
Disseminate Recurrent Folliculitis and Hidradenitis Suppurativa Are Associated Conditions: Results From a Retrospective Study of 131 Patients With Down Syndrome and a Cohort of 12,351 Pediatric Controls
Down syndrome linked to more butt folliculitis.RetrospectiveLow qualityRelated question
12,482 people2019
People with Down syndrome had much higher rates of both skin conditions than controls, and buttocks were the most commonly affected area for the recurrent folliculitis
Who was studied
Children, teens, and young adults with Down syndrome, compared to a large group of pediatric patients without Down syndrome
What they received
Having Down syndrome (trisomy 21)
Compared with
Pediatric patients without Down syndrome
Main outcome
How common disseminated recurrent folliculitis (DRF) and hidradenitis suppurativa (HS) were in each group, and which body areas were affected
Quality
This was a single-center retrospective study without randomization, so it can show an association but not prove why it happens.
Limitations
Retrospective design from one center; does not describe the general population asking about buttock pimples, only people with Down syndrome versus pediatric controls.
Taken word for word from the abstract
- n 131 patients with DS
- n 12,351 pediatric controls
- population 131 patients with DS, aged 4-36 years, followed at the Dermatology Unit and Down Syndrome Regional Center of Bologna University
- intervention patients carrying trisomy 21
- comparator 12,351 pediatric controls
- primaryOutcome To assess the prevalence of HS and DRF by comparing a cohort of patients carrying trisomy 21 vs pediatric controls
- result In DS patients, DRF and HS showed a prevalence of, respectively, 6.8% and 24.4%, while 5.3% of patients presented both diseases. In the control group the prevalence for HS+ and DRF+ was 0.5% and 1.2%, respectively
- result Buttocks were the most frequently affected body area for DRF followed by the inguinocrural area
Dermatol Pract Concept · PMID 31384491 · Read it on PubMed ↗
De Vita et al. 2018
Mechanical Stress as a Cause of Hidradenitis Suppurativa: A Lesson from a Patient with a Monster Hernia
Friction and pressure may cause boils.Case seriesVery low qualityRelated question
1 people2018
The patient developed inflammatory nodules, cysts, and scars specifically in the skin area under constant friction and pressure from the hernia and clothing, supporting mechanical stress as a cause.
Who was studied
a 54-year-old man with a giant abdominal hernia and no prior history of hidradenitis suppurativa
What they received
ongoing mechanical stress (friction and pressure) on the skin from the hernia and tight trousers/belt
Compared with
none reported
Main outcome
development of hidradenitis suppurativa-like skin lesions (nodules, cysts, scars)
Quality
This is a single patient case report, so it cannot reliably show cause and effect for the general population.
Limitations
Single case with no comparison group; conclusions are based on clinical reasoning about one patient's hernia-related skin lesions.
Taken word for word from the abstract
- n A 54-year-old man without any previous history of HS developed chronic, recurrent, inflammatory nodules, cysts, and depressed scars at the location of a giant abdominal hernia
- population A 54-year-old man without any previous history of HS developed chronic, recurrent, inflammatory nodules, cysts, and depressed scars at the location of a giant abdominal hernia
- intervention the mechanical stress in the abdominal region was greater than the one occurring at the other folds due to the pressure of the trousers and belt
- primaryOutcome developed chronic, recurrent, inflammatory nodules, cysts, and depressed scars at the location of a giant abdominal hernia
- result suggesting that mechanical stress was an important pathogenic factor for HS development
- comparator No lesions occurred in other inverse areas generally affected by HS, such as the axillary and anogenito-crural regions.
Acta Dermatovenerol Croat · PMID 30390729 · Read it on PubMed ↗
Boer et al. 2016
Boils at Frictional Locations in a Patient with Hidradenitis Suppurativa
Friction may trigger boil-like skin lesions.Case seriesVery low qualityRelated question
1 people2016
she developed new boil-like lesions exactly where her bra strap rubbed, suggesting friction can trigger these lesions in people prone to hidradenitis suppurativa
Who was studied
33-year-old obese woman with long-standing hidradenitis suppurativa affecting armpits, groin, and buttocks
What they received
having hidradenitis suppurativa plus mechanical friction from a bra strap
Compared with
no comparator, single case observation
Main outcome
location and development of boil-like inflamed skin lesions
Quality
This is a single patient case report, so it cannot reliably show what causes lesions in general.
Limitations
Single case report; friction as a cause is based on anecdotal evidence and this patient already had a diagnosed chronic condition, obesity, smoking, and family history that could also contribute.
Taken word for word from the abstract
- n A 33-year old woman presented with an 18-year history
- population A 33-year old woman presented with an 18-year history of chronic, recurrent, inflammatory nodules in the axillae, the groin, the pubic region, and to a lesser extent the abdomen and buttocks.
- intervention a superficial nodule and follicular papules were observed, exactly coinciding with the red stripe caused by mechanical stress (friction and pressure) of the bra edge
- comparator There was no skin fold present on the location of the HS lesions, and there were no lesions observed in the intermammary region or on the side of the breasts in contact with the skin of the thorax (skin to skin contact)
- primaryOutcome HS-like lesions at the position of the bra strap, suggesting that mechanical stress was an external pathogenic factor for HS development
- result It is postulated that these lesions may have been induced by mechanical stress, additionally triggered by the pro-inflammatory state of the obese body.
Acta Dermatovenerol Croat · PMID 28128084 · Read it on PubMed ↗
Loddé et al. 2016
Skin Diseases Affecting High-Level Competition Sailors: Descriptive Study Carried Out During the 2012 AG2R Transatlantic Boat Race
More butt folliculitis after sailingProspective cohortVery low qualityRelated question
28 people22 to 24 days later
more buttock folliculitis, fungal infections, and hand hyperkeratosis seen after the race than before
Who was studied
competitive sailors during a long ocean race
What they received
no treatment tested; observed skin conditions before and after the race
Compared with
skin condition at departure versus at arrival after 22-24 days at sea
Main outcome
skin disorders seen in sailors, including buttock folliculitis
Quality
small, non-randomized descriptive study with incomplete follow-up (only 18 of 32 completed) and no statistical comparison, so it can't prove why acne-like bumps happen.
Limitations
Only 56% of sailors completed the arrival questionnaire, there was no control group, and conditions on a transatlantic race (poor hygiene, friction gear, sweat) differ from everyday life.
Taken word for word from the abstract
- n Twenty-eight of 32 skippers (88%) participated in departure data collection
- population a population of sport sailors
- intervention Clinical examinations were conducted, photographs taken, and questionnaires containing 34 questions were handed out before departure and on arrival
- comparator before departure and on arrival, 22 to 24 days later
- primaryOutcome The primary objective of this study was to identify skin disorders encountered in a population of sport sailors.
- result Compared with skin diseases documented on departure, there was an increased amount of folliculitis on the buttocks, fungal infections, and hyperkeratosis of the hands on arrival.
- followUp 22 to 24 days later
Wilderness Environ Med · PMID 26948552 · Read it on PubMed ↗

All 120 studiesEvery study that answered the question, with its design, size and result.

The other 112 studiesEverything else the search returned, including anything retracted.

Zhang et al. 2026
Successful treatment of hidradenitis suppurativa with vunakizumab: a case report and literature review
Skin lesions cleared, no recurrence.Case seriesVery low quality
1 people10 months
complete resolution of nodules, abscesses, and tunnels and no recurrence or significant adverse events during 10 months of follow-up
Who was studied
a 17-year-old boy with 5-year history of recurrent painful nodules and abscesses on the buttocks
What they received
vunakizumab, an anti-IL-17A monoclonal antibody
Compared with
no direct comparator; previously treated with conventional antibiotics
Main outcome
resolution of nodules, abscesses, and tunnels
Quality
This is a single patient case report, so it cannot show whether the treatment would work for others.
Limitations
Single case report with no control group, making it impossible to know if improvement was due to the drug.
Taken word for word from the abstract
- population a 17-year-old boy with a 5-year history of recurrent painful nodules and abscesses on the buttocks
- intervention vunakizumab, a domestically developed anti-IL-17A monoclonal antibody
- comparator had responded poorly to conventional antibiotics
- primaryOutcome complete resolution of nodules, abscesses, and tunnels
- result complete resolution of nodules, abscesses, and tunnels and no recurrence or significant adverse events during 10 months of follow-up
- n 17-year-old boy
Front Immunol · PMID 42591326 · Read it on PubMed ↗
Fuchs et al. 2026
Two-Stage Surgical Management of Anogenital Hidradenitis Suppurativa in Patients on Biologic Therapy: A Retrospective Case Series
Surgery healed severe gluteal HS.Case seriesVery low qualityRelated question
5 people19.2 months
all patients healed well with over 90% graft success and no disease came back during follow-up
Who was studied
men with severe, long-term hidradenitis suppurativa (boil-like skin disease) affecting the perineal, anorectal, genital or gluteal area that hadn't responded to biologic drugs
What they received
two-stage surgical removal of the affected skin, wound vacuum therapy, then skin grafting
Compared with
none reported (single-arm case series, no comparison group)
Main outcome
wound healing and recurrence of disease after surgery
Quality
Only five patients were studied in a retrospective series with no comparison group, so the results can't be generalized.
Limitations
Retrospective design, very small sample of five male patients, no control group, single centre.
Taken word for word from the abstract
- n This single-centre retrospective case series included five male patients
- population five male patients with Hurley stage III perineal, anorectal, genital or gluteal disease treated surgically between 2021 and 2023 following failure of biologic therapy
- intervention two-stage radical excision, negative-pressure wound therapy and reconstruction with meshed split-thickness skin grafts
- comparator This single-centre retrospective case series included five male patients
- primaryOutcome All patients achieved more than 90% graft take and complete wound healing.
- result No recurrence occurred during a median follow-up of 19.2 months.
- followUp median follow-up of 19.2 months
Int Wound J · PMID 41884971 · Read it on PubMed ↗
Lim et al. 2026
Presentations of Cutaneous Disease in Various Skin Pigmentations: Keratosis Pilaris
Describes keratosis pilaris, a bump mimic.Narrative reviewVery low qualityRelated question
size not given2026
the abstract describes clinical features and mimics of keratosis pilaris, not a treatment outcome
Who was studied
people with keratosis pilaris across different skin tones
What they received
not applicable (descriptive review of skin findings)
Main outcome
visual identification of keratosis pilaris across skin pigmentations
Quality
this is a descriptive review of skin appearance, not a study testing a treatment or cause, so it cannot show why pimples occur or what works.
Limitations
abstract does not report a study design with participants, comparison, or measured outcome; it is an educational review of disease appearance.
Taken word for word from the abstract
- population The clinical images in this review focus on identifying KP across the spectrum of skin tones.
- primaryOutcome The clinical images in this review focus on identifying KP across the spectrum of skin tones.
- result Common mimicking diagnoses include folliculitis, acne vulgaris, and milia.
- intervention Education about KP and its treatment may alleviate psychological distress and reduce symptoms.
HCA Healthc J Med · PMID 41810251 · Read it on PubMed ↗
Flor et al. 2025
A Case of Porokeratosis Ptychotropica Treated with Cryotherapy
Rare skin patches cleared after freezing treatment.Case seriesVery low qualityRelated question
1 people2025
the lesions completely cleared after two rounds of cryotherapy, leaving only mild lighter skin patches and no significant scarring
Who was studied
a 76-year-old woman with skin lesions between the buttocks and near the vulva
What they received
freezing treatment (cryotherapy) applied to the skin lesions
Compared with
no comparison treatment; lesions had previously not responded to topical or oral antifungal treatment
Main outcome
whether the skin lesions cleared up after treatment
Quality
This is a single patient case report, so it cannot show whether this treatment or condition applies to most people with similar skin problems.
Limitations
Only one patient was studied, there is no comparison group, and the condition described (porokeratosis ptychotropica) is a rare, specific skin disorder rather than common pimples or acne on the buttocks.
Taken word for word from the abstract
- population A 76-year-old female with no prior relevant history was referred due to a one-year-long history of cutaneous lesions in the intergluteal region
- intervention Two cycles of cryotherapy were performed (20 seconds per lesion).
- comparator which had not responded to topical or oral antifungal
- primaryOutcome On follow-up, total resolution of lesions was observed
- result On follow-up, total resolution of lesions was observed, with residual hypopigmentation without significant scarring being observed.
- n A 76-year-old female
Acta Dermatovenerol Croat · PMID 41804627 · Read it on PubMed ↗
Du et al. 2026
Efficacy and safety of the Exfoliate-Dissolve-Repair skin care approach in the treatment of keratosis pilaris: a randomized controlled clinical trial study protocol
No results yet, trial plannedRegistered trial, no results postedLow quality
72 people4 weeks
This is a trial protocol; no results are reported yet
Who was studied
Adults aged 18-35 with keratosis pilaris (bumpy skin on arms, thighs, buttocks)
What they received
Exfoliate-Dissolve-Repair skin care (body scrub plus moisturizing lotion)
Compared with
0.1% retinoic acid cream
Main outcome
Improvement in follicular bumps and skin roughness/keratinization
Quality
This is only a study protocol for a planned trial, so no outcome data exist yet to judge effectiveness.
Limitations
Single center study; only a protocol, so no results, effectiveness, or safety data are yet available.
Taken word for word from the abstract
- population targeting cases of KP aged 18-35 years
- n Participants (n = 72) were randomly assigned
- intervention The treatment group received EDR comprehensive skin care intervention
- comparator the control group received 0.1% retinoic acid cream intervention
- primaryOutcome The main outcome measures include the improvement index of follicular papules and evaluation of skin keratinization degree
- result This protocol has been registered prospectively in ISRCTN under the ISRCTN14455606 on April 6, 2025.
- followUp The trial includes a 4-week treatment period
Trials · PMID 41736049 · Read it on PubMed ↗
Safir et al. 2026
Fractional Microneedling Radiofrequency for Hidradenitis Suppurativa: A Real-World Retrospective Study Demonstrating Clinical Efficacy and Safety Across Diverse Anatomical Sites
Improved hidradenitis suppurativa lesions, not ordinary pimples.RetrospectiveLow qualityRelated question
17 people2026
94.1% of patients showed clinical improvement and 52.9% achieved a ≥55% reduction in severity score
Who was studied
patients with moderate-to-severe hidradenitis suppurativa (a chronic inflammatory skin condition, not simple pimples)
What they received
fractional microneedling radiofrequency (Morpheus8) treatment
Compared with
no comparator group; outcomes measured before and after treatment
Main outcome
change in hidradenitis suppurativa severity score (IHS4) and proportion achieving ≥55% reduction (IHS4-55)
Quality
This was a small, retrospective study with no control group, so it can't reliably show the treatment caused the improvement.
Limitations
Retrospective design, small sample size, no control group, and it studies a specific severe disease (hidradenitis suppurativa) rather than common buttock pimples.
Taken word for word from the abstract
- population This retrospective analysis included 25 HS patients treated at a tertiary dermatology center.
- n Seventeen patients who completed ≥ 2 FMR sessions were included in the efficacy analysis.
- intervention To evaluate the real-world efficacy and safety of Morpheus8-based FMR treatment in patients with HS.
- comparator This retrospective analysis included 25 HS patients treated at a tertiary dermatology center.
- primaryOutcome Outcomes were assessed by the International Hidradenitis Suppurativa Severity Score System (IHS4) and IHS4-55 (≥ 55% reduction).
- result Sixteen of the 17 patients (94.1%) evaluated for efficacy showed clinical improvement, and nine (52.9%) achieved an IHS4-55 response.
J Cosmet Dermatol · PMID 41732823 · Read it on PubMed ↗
Lai et al. 2026
The Roles of Keratinocytes in the Initiation, Progression and Maintenance of Hidradenitis Suppurativa
Skin cell abnormalities may drive this condition.Narrative reviewLow qualityRelated question
size not given2026
review concludes keratinocytes contribute to inflammation and disease progression through genetic, metabolic and cytokine abnormalities
Who was studied
people with hidradenitis suppurativa (a skin condition causing nodules and abscesses in armpits, groin and buttock areas)
Main outcome
understanding how skin cells (keratinocytes) contribute to disease development
Quality
this is a narrative review summarizing existing research rather than a study with its own patient data or statistical testing.
Limitations
abstract states the exact cause of the disease remains unclear and this is a synthesis of other evidence, not new patient data
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is an autoinflammatory skin disease characterised by deep-seated and painful nodules, abscesses and draining tunnels that extensively penetrate the dermis in the axillae, inguinal and gluteal areas.
- primaryOutcome This review synthesises current evidence on KCs in HS, emphasising their genetic background and metabolic dysregulation.
- result The initiation, progression and maintenance of the disease may involve functional abnormalities in keratinocytes (KCs), significantly contributing to the production of proinflammatory cytokines within and around the affected tissue and increased infiltration of immune cells.
- limitations The exact aetiology remains unclear.
Exp Dermatol · PMID 41560364 · Read it on PubMed ↗
Nichols et al. 2026
Verruciform Xanthoma Within the Cyst Lining of Hidradenitis Suppurativa
Describes one rare skin finding, not a cause.Case seriesVery low qualityRelated question
1 people2026
the cyst lining showed an unusual pattern called verruciform xanthoma, not previously described in hidradenitis suppurativa
Who was studied
56-year-old man with long-standing severe hidradenitis suppurativa affecting the buttock area
What they received
not applicable - this is a pathology case report, not a treatment study
Compared with
none
Main outcome
microscopic appearance of tissue removed from a draining sinus tract
Quality
this is a single patient case report describing a tissue finding, not a treatment or outcome study, so it cannot show what causes or helps buttock pimples.
Limitations
single case, no treatment tested, does not address typical acne/pimples, focuses on a severe chronic condition (HS) with rare microscopic finding
Taken word for word from the abstract
- n a 56-year-old man with long-standing, Hurley Stage 3 HS affecting the gluteal region
- population a 56-year-old man with long-standing, Hurley Stage 3 HS affecting the gluteal region
- intervention Following surgical excision of a draining sinus tract, histopathology revealed a squamous-lined follicular cyst consistent with HS
- comparator Retrospective review of prior HS specimens did not show similar changes.
- primaryOutcome histopathology revealed a squamous-lined follicular cyst consistent with HS, with approximately 10% of the cyst lining displaying features characteristic of VX
- result approximately 10% of the cyst lining displaying features characteristic of VX, including papillomatous acanthosis, parakeratosis with neutrophils, and underlying foamy macrophages
J Cutan Pathol · PMID 41400110 · Read it on PubMed ↗
Chang et al. 2026
Ethnic Differences in Hidradenitis Suppurativa: Comorbidities, Lesion Distribution, and Disease Severity in a Taiwanese Population
Men, smokers more prone to butt lesions.RetrospectiveLow qualityRelated question
512 people2026
Men and smokers were more likely to have buttock lesions, while women and obese patients were more likely to have armpit/groin lesions; male sex, smoking, and armpit involvement predicted more severe disease
Who was studied
Taiwanese patients diagnosed with hidradenitis suppurativa compared to matched people without it
What they received
being male or a current smoker
Compared with
being female or a non-smoker
Main outcome
whether skin lesions occurred on the buttocks (gluteal area) versus armpits/groin, and disease severity
Quality
It's a retrospective records review comparing groups, which can show links but not prove what actually causes the lesions.
Limitations
Retrospective design using clinical records, and it studies a specific chronic inflammatory disease (hidradenitis suppurativa) rather than typical acne-like pimples.
Taken word for word from the abstract
- n A total of 512 patients with HS and 1,536 reference individuals were identified.
- population We conducted a retrospective analysis of clinical records for patients with HS diagnosed between 2006 and 2022 at two tertiary referral hospitals in Taiwan.
- intervention Men had 4.2 times the odds of developing gluteal lesions but only 0.5 times the odds of axillary or inguinal involvement compared to women.
- comparator Current smokers had 2.8 times the odds of gluteal involvement but 0.6 times the odds of having axillary lesions.
- primaryOutcome logistic regression identified predictors for lesion distribution and disease severity
- result Male sex and active smoking could predict for gluteal involvement, while female sex and obesity for axillary involvement.
Dermatology · PMID 41248121 · Read it on PubMed ↗
Gunnarsdottir et al. 2025
[Severe hidradenitis suppurativa treated with acellular fish skin - A case report and discussion of the disorder]
Fish-skin graft healed severe hidradenitis suppurativa.Case seriesVery low qualityRelated question
1 people21 months after surgery on the right side and 7 months after surgery on the left side
symptom-free on the right side 21 months after surgery and minimal symptoms on the left side 7 months after surgery
Who was studied
a man with severe hidradenitis suppurativa on both buttocks who had already been treated with biologics
What they received
debridement (surgical cleaning) combined with acellular fish skin graft
Compared with
usual extensive surgery with skin transplantation or flap closure
Main outcome
symptom resolution after surgery
Quality
This is a single patient case report with no control group, so it cannot show whether the treatment truly works better than alternatives.
Limitations
Only one patient was treated and described, limiting how much the result can be generalized.
Taken word for word from the abstract
- n This case report presents a patient with severe disease on both buttocks
- population a patient with severe disease on both buttocks, already treated with biologics
- intervention treatment with debridement and acellular fish skin
- comparator requiring skin transplantation or flaps for closure
- primaryOutcome symptom-free on the right side 21 months after surgery
- result symptom-free on the right side 21 months after surgery and has minimal symptoms on the left side 7 months after surgery
Laeknabladid · PMID 41201033 · Read it on PubMed ↗
Abeledo et al. 2025
[Hidradenitis Suppurativa: Most Relevant Epidemiological Characteristics of an Underdiagnosed Disease. A Cross-Sectional Study]
Butt lesions seen in some HS patientsRetrospectiveLow qualityRelated question
205 people2025
the gluteal (buttock) area was affected in 13.7% of patients, less often than the armpits or groin
Who was studied
patients diagnosed with Hidradenitis Suppurativa at a university hospital
What they received
none - observational review of diagnosed patients' records, treatments described but not compared
Main outcome
how common and where Hidradenitis Suppurativa lesions occur, plus treatment response
Quality
this is a retrospective, descriptive chart review with no comparison group, so it can describe patterns but not prove what causes or treats the lesions
Limitations
retrospective design based on medical records, no control group, and it studies people already diagnosed with a specific chronic disease rather than the general population asking about buttock pimples
Taken word for word from the abstract
- population based on the medical records of patients diagnosed with HS at the Hospital Universitario Austral between 2000 and 2024
- n A total of 205 patients were analyzed
- intervention evaluate the treatments used and their therapeutic responses
- primaryOutcome determine the prevalence of HS in a hospital population, describe its most relevant clinical and ultrasound characteristics, and evaluate the treatments used and their therapeutic responses
- result The most affected areas were the axillae (74.6%), inguinal region (34.1%), and gluteal region (13.7%)
Rev Fac Cien Med Univ Nac Cordoba · PMID 41032437 · Read it on PubMed ↗
Sin-Soler et al. 2025
Hidradenitis suppurativa in paediatric patients with Down syndrome: a comparative study of 116 participants
Linked to hidradenitis suppurativa, not typical acneRetrospectiveLow qualityRelated question
116 people2025
32 of 116 children with Down syndrome developed hidradenitis suppurativa, most commonly affecting the groin and buttocks, usually mild
Who was studied
Children under 18 with Down syndrome
What they received
Having Down syndrome (studied for hidradenitis suppurativa development)
Compared with
Children with Down syndrome alone (without HS)
Main outcome
Presence, characteristics and severity of hidradenitis suppurativa (a skin condition causing boil-like bumps, often in groin and buttocks)
Quality
This is a small, single-centre retrospective study describing a specific population (children with Down syndrome), which limits how much it can tell us about butt pimples in general.
Limitations
Retrospective nature, small sample size and data collection from a single centre
Taken word for word from the abstract
- n HS was diagnosed in 32 of 116 patients with DS.
- population children (aged < 18 years) with DS
- intervention Hidradenitis suppurativa (HS) seems to be more prevalent in patients with Down syndrome (DS)
- comparator make comparisons with children with DS alone
- primaryOutcome To describe the demographics, clinical characteristics and severity of HS in children with DS
- result The groin (n = 24/32; 75%) and buttocks (n = 21/32; 66%) were the most commonly affected areas.
- limitations The limitations of this study include its retrospective nature, small sample size and data collection from a single centre.
Clin Exp Dermatol · PMID 40498928 · Read it on PubMed ↗
Aşkın et al. 2025
The comorbidities of hidradenitis suppurativa
Not about ordinary butt pimples.Narrative reviewVery low qualityRelated question
size not given2025
the abstract lists conditions that often occur with hidradenitis suppurativa, including obesity, diabetes, depression, and a rare risk of skin cancer in perianal/gluteal lesions, but does not test or report on acne/pimples on the buttocks specifically
Who was studied
people with hidradenitis suppurativa (a chronic inflammatory skin disease)
Main outcome
what other health conditions and complications occur alongside hidradenitis suppurativa
Quality
this is a narrative review listing associated conditions, not a study testing any treatment or cause, and it does not address ordinary buttock pimples at all
Limitations
abstract does not describe methods, study selection, or evidence quality; it does not address common buttock pimples, only hidradenitis suppurativa, a distinct and more severe condition
Taken word for word from the abstract
- population Hidradenitis suppurativa is a chronic inflammatory disease that dramatically decreases the quality of life of afflicted patients.
- result A number of factors may coexist with hidradenitis suppurativa, including stigmatization, social isolation, tobacco use, alcohol abuse, suicidal ideation, depression, other psychiatric disorders, and medical comorbidities such as obesity, diabetes mellitus, hypertension, dyslipidemia, metabolic syndrome, coronary artery disease, and polycystic ovarian syndrome.
- result A rare but important long-term complication of hidradenitis suppurativa is squamous cell cancer; men with perianal, gluteal, or perineal lesions are at increased risk, and multiple biopsies should be taken in case of any suspicious lesions.
- primaryOutcome These comorbidities should be kept in mind while planning the treatment.
Clin Dermatol · PMID 40414610 · Read it on PubMed ↗
Nielsen et al. 2025
Hidradenitis suppurativa among patients with new-onset inflammatory bowel disease-results from the IBD Prognosis Study
Butt boils linked to bowel disease.Prospective cohortModerate qualityRelated question
527 people2025
Hidradenitis suppurativa was found in 5.5% of patients with Crohn's disease and 8% with ulcerative colitis, most often affecting the groin and buttocks, and these patients had higher BMI, more other inflammatory conditions, and more severe bowel disease
Who was studied
adults newly diagnosed with inflammatory bowel disease (Crohn's disease or ulcerative colitis)
What they received
having hidradenitis suppurativa (a chronic skin condition causing boils, often in the groin and buttocks)
Compared with
IBD patients without hidradenitis suppurativa
Main outcome
how common hidradenitis suppurativa is and its clinical features in people with new IBD
Quality
It's a large population-based cohort study, but it only shows an association between skin boils and bowel disease, not what causes either one.
Limitations
Observational cohort study showing association only; no data on causes of hidradenitis suppurativa in people without IBD.
Taken word for word from the abstract
- n Of 527 patients with new-onset IBD
- population a population-based cohort of newly diagnosed IBD patients
- intervention Hidradenitis suppurativa was prevalent in 5.5% (n = 29), 8% (n = 16), and 3.9% (n = 12) of patients with CD and UC
- comparator Statistical comparisons were performed between IBD patients with and without HS
- primaryOutcome This study aimed to assess the prevalence and clinical characteristics of HS in a population-based cohort of newly diagnosed IBD patients
- result Patients with concomitant HS were most frequently affected in the groin area and buttocks, had significantly higher body mass index (BMI) (26.4 vs 24.2 kg/m², P = .036), and had higher prevalence of EIMs (79.3% vs 41.2%, P < .001) compared to patients with IBD alone.
J Crohns Colitis · PMID 40251895 · Read it on PubMed ↗
Peng et al. 2025
Porokeratosis ptychotropica and concurrent condyloma acuminata respond well to photodynamic therapy
Rare skin condition improved with light therapyCase seriesVery low qualityRelated question
1 people6-months follow-up
significant clinical and symptom improvement at 2 months, and symptom-free at 6 months
Who was studied
a 73-year-old man with patchy hyperkeratotic lesions and verrucous growths over his buttocks, perianal area, gluteal cleft, and scrotum
What they received
photodynamic therapy using 5-aminolevulinic acid gel and red light sessions
Main outcome
clinical and symptom improvement of the skin lesions
Quality
This is a single case report of one patient, so it cannot show whether this treatment works in general.
Limitations
Single patient case report with no control group, describing a rare condition (porokeratosis ptychotropica with genital warts) rather than common buttock pimples.
Taken word for word from the abstract
- n a 73-year-old man
- population Here we present the case of a 73-year-old man with patchy hyperkeratotic lesions and verrucous growths over his buttocks, perianal area, gluteal cleft, and scrotum
- intervention Three monthly topical photodynamic therapy (PDT) sessions with 78 mg/g 5-aminolevulinic acid (5-ALA) gel and 635 nm red light (total 78 J/cm2) were performed over the patient's perianal and buttock region, and two monthly PDT sessions were performed over his scrotum.
- primaryOutcome At 2-month follow-up, the patient reported significant clinical and symptoms improvement
- result At 2-month follow-up, the patient reported significant clinical and symptoms improvement, and remains symptom-free at 6-months follow-up.
Photodiagnosis Photodyn Ther · PMID 40204208 · Read it on PubMed ↗
Wang et al. 2025
Multidisciplinary approach to squamous cell carcinoma originating in hidradenitis suppurativa lesions: a case report
Rare cancerous HS wound healed with treatment.Case seriesVery low qualityRelated question
1 people201 days
the wound fully healed after 201 days with no recurrence seen during follow-up
Who was studied
30-year-old man with long-term hidradenitis suppurativa and a non-healing wound on his buttock
What they received
combined treatment by a team of specialists (chemotherapy, wound care, and surgery to remove the lesions)
Compared with
no comparison group
Main outcome
complete healing of the wound and no cancer recurrence
Quality
this is a single patient's case report, so it cannot show whether this approach works in general.
Limitations
only one patient was studied, and this involved a rare cancer arising from long-standing hidradenitis suppurativa, not ordinary buttock pimples.
Taken word for word from the abstract
- n a 30-year-old male patient with HS
- population a 30-year-old male patient with HS, with an eight-year history of a recurrent abscess and a nonhealing ulcer-like wound on his right buttock
- intervention administer various treatments including chemotherapy, wound care, and surgical removal of lesions
- comparator A multidisciplinary team was established, comprising an oncologist, a plastic surgeon and two enterostomal therapists
- primaryOutcome The wound completely healed 201 days later, without any recurrence observed during follow-up.
- result The wound completely healed 201 days later, without any recurrence observed during follow-up.
J Wound Care · PMID 40047818 · Read it on PubMed ↗
Radhakrishna et al. 2025
Impaired Molecular Mechanisms Contributing to Chronic Pain in Patients with Hidradenitis Suppurativa: Exploring Potential Biomarkers and Therapeutic Targets
Found gene markers tied to chronic pain in HS, not pimples.Case-controlVery low qualityRelated question
48 people2025
found 253 genes with different methylation patterns in HS patients, many linked to pain, inflammation, and other body processes
Who was studied
people with hidradenitis suppurativa (a chronic skin condition affecting hairy, sweat-gland-rich areas like armpits, groin, buttocks) compared to healthy people
What they received
having hidradenitis suppurativa (not a tested treatment)
Compared with
healthy people without the condition
Main outcome
patterns of DNA chemical markers (methylation) on genes linked to pain sensitivity
Quality
This is a small, exploratory lab study of blood DNA markers in only 24 patients, not a study of acne or pimple causes or treatments.
Limitations
Small sample size (24 patients, 24 controls); exploratory molecular/epigenetic study not testing any treatment or directly addressing pimple formation on the buttocks.
Taken word for word from the abstract
- population 24 patients with HS and 24 healthy controls
- intervention Hidradenitis suppurativa (HS) is a chronic skin condition that primarily affects areas with dense hair follicles and apocrine sweat glands, such as the underarms, groin, buttocks, and lower breasts.
- comparator 24 healthy controls
- primaryOutcome We aim to identify molecular markers of chronic pain in HS patients.
- result We identified 253 significantly differentially methylated CpG sites across 253 distinct genes regulating pain sensitization in HS, including 224 hypomethylated and 29 hypermethylated sites.
- n a group of 24 patients with HS and 24 healthy controls
Int J Mol Sci · PMID 39940809 · Read it on PubMed ↗
Maskan Bermudez et al. 2025
Management of hidradenitis suppurativa in the inpatient setting: a clinical guide
Guidance only, no outcome data.GuidelineLow qualityRelated question
size not given2025
the abstract gives management guidance but does not report trial results or outcome data
Who was studied
people hospitalized with severe flares of hidradenitis suppurativa, a chronic skin condition affecting armpits, groin, buttocks and thighs
What they received
inpatient management including specialist consultations, pain control, rescue therapy, surgical planning, and early biologic drugs
Main outcome
improved flare management and clinical outcomes
Quality
this is an expert guidance review, not a study testing treatment effects, so it can't show whether a specific treatment works.
Limitations
it is a narrative clinical guide for inpatient care of severe disease, not a study of causes or typical mild cases of buttock pimples.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic inflammatory disease that affects the axilla, inframammary folds, buttocks, inner thighs, and anogenital regions.
- intervention multimodal treatments, particularly biologics, are needed to achieve clinical remission in severe disease.
- primaryOutcome Streamlining care during hospitalization for the early initiation of these therapies can significantly improve flare management and overall clinical outcomes for HS patients.
- result This review aims to improve care for HS by providing clear and comprehensive guidance on its management in the inpatient setting.
Arch Dermatol Res · PMID 39777571 · Read it on PubMed ↗
Zahid et al. 2025
Questionnaire-Based Global Prevalence of Hidradenitis Suppurativa: A Systematic Review and Meta-Analysis
About 2.5% have hidradenitis suppurativa.Meta-analysisModerate qualityRelated question
49,971 people2025
pooled prevalence of hidradenitis suppurativa was 2.5% of people surveyed
Who was studied
adults surveyed with a validated questionnaire about recurring boils/abscesses in skin folds (armpits, groin, genitals, buttocks)
What they received
no treatment tested; this is a prevalence survey of hidradenitis suppurativa symptoms
Compared with
none - no comparison group, just prevalence estimation across studies
Main outcome
how common hidradenitis suppurativa (recurrent boils) is worldwide
Quality
it pools many large surveys but the authors warn of heterogeneity between studies and missing data from some world regions.
Limitations
heterogeneity and sparse data from the Global South; estimate should be interpreted with caution
Taken word for word from the abstract
- n The meta-analysis encompassing 49,971 participants revealed a global HS prevalence of 2.5% (95% CI, 1.8-3.5%).
- population "Have you for the past 6 months had 2 or more boils/abscesses in any of the below locations: in the axilla, in the groin, around your genitals, on the buttocks, several locations i.e., first the buttocks then the axilla, etc.?"
- intervention This systematic review was prospectively registered on PROSPERO and adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.
- comparator A pooled prevalence with 95% confidence interval (CI) was calculated with a random-effects model.
- primaryOutcome Thus, we aimed to estimate a global HS prevalence based on studies using homogeneous validated questions.
- result revealed a global HS prevalence of 2.5% (95% CI, 1.8-3.5%)
Dermatology · PMID 39715604 · Read it on PubMed ↗
Radhakrishna et al. 2024
DNA methylation patterns of circadian and ultradian genes are altered in the peripheral blood of patients with hidradenitis suppurativa
Immune gene changes found in HS patientsCase-controlLow qualityRelated question
48 people2024
several circadian and ultradian genes showed altered (mostly reduced) methylation in HS patients, linked to inflammation and immune pathways
Who was studied
people with hidradenitis suppurativa (a chronic inflammatory skin condition affecting areas like underarms, groin, and buttocks) compared to healthy people
What they received
none (this study did not test a treatment; it measured DNA methylation patterns)
Compared with
healthy control subjects
Main outcome
patterns of DNA methylation (chemical marks on genes) in blood, focusing on circadian and ultradian clock genes
Quality
This is a small observational study of blood samples, not a treatment trial, so it cannot tell us whether anything helps or causes buttock pimples.
Limitations
Small sample size (24 cases, 24 controls); studies hidradenitis suppurativa specifically, not ordinary acne/pimples; blood methylation rather than skin tissue; no intervention tested.
Taken word for word from the abstract
- population peripheral blood from 24 HS cases and 24 controls
- n peripheral blood from 24 HS cases and 24 controls
- comparator 24 HS cases and 24 controls
- primaryOutcome genome-wide DNA methylation patterns
- result several circadian and ultradian genes were differentially methylated in HS patients, predominantly exhibiting hypomethylation
- intervention We analyzed genome-wide DNA methylation patterns in peripheral blood from 24 HS cases and 24 controls
Front Immunol · PMID 39669567 · Read it on PubMed ↗
Lamberg et al. 2024
Nivolumab-induced hidradenitis suppurativa: a case report
Cancer drug triggered butt boils.Case seriesVery low qualityRelated question
1 people2024
he developed symmetric recurrent nodules and boils in intertriginous areas, diagnosed as stage II hidradenitis suppurativa of the groin and gluteal cleft
Who was studied
a 44-year-old man with metastatic clear cell renal cell cancer
What they received
nivolumab immunotherapy
Compared with
none
Main outcome
development of hidradenitis suppurativa (boils/nodules) in skin folds
Quality
This is a single patient case report, so it cannot show how common or likely this cause is for anyone else.
Limitations
Single case report; no control group; cancer immunotherapy patient, not a general population with buttock pimples.
Taken word for word from the abstract
- population a 44-year-old man with metastatic clear cell renal cell cancer undergoing treatment with nivolumab immunotherapy
- intervention nivolumab immunotherapy
- result he developed symmetric recurrent nodules and boils in intertriginous areas, diagnosed as stage II hidradenitis suppurativa of the groin and gluteal cleft
- primaryOutcome diagnosed as stage II hidradenitis suppurativa of the groin and gluteal cleft
- n a 44-year-old man
- comparator We present a 44-year-old man
Dermatol Online J · PMID 39644467 · Read it on PubMed ↗
Alpsoy et al. 2025
Clinical Features and Natural Course of Hidradenitis Suppurativa in Turkey: A Multicenter Study
Butt bumps may be hidradenitis suppurativa.RetrospectiveLow qualityRelated question
827 people2025
Disease most often started in the armpit, then groin and buttock areas, and was more severe in men; antibiotics improved symptoms while stress worsened them
Who was studied
patients diagnosed with hidradenitis suppurativa in Turkey
What they received
various treatments and factors such as antibiotics, biological therapy, and laser epilation
Compared with
comparison between male and female patients
Main outcome
the natural course and severity of hidradenitis suppurativa
Quality
This was a retrospective, cross-sectional study that relied on patient memory and had no control group, so it can't prove cause and effect.
Limitations
The chronological order of symptoms was recorded retrospectively, which can introduce recall bias, and there is no comparison group of people without hidradenitis suppurativa.
Taken word for word from the abstract
- n This cross-sectional study included 827 patients.
- population This cross-sectional study included 827 patients.
- intervention Biological therapy in men, laser epilation and pregnancy in women were significant alleviating factors
- comparator investigate the natural history of HS and its gender differences
- primaryOutcome we aimed to investigate the natural history of HS and its gender differences
- result The axilla was the most common onset area followed by the inguinal and gluteal regions.
- result The disease ran a more severe course in men.
- limitations The chronological order of the clinical manifestations for each patient was recorded retrospectively.
Dermatology · PMID 39571540 · Read it on PubMed ↗
Loh et al. 2024
Malignant Transformation in Porokeratosis Ptychotropica: A Systematic Review
Rare skin lesion, not ordinary pimples.Systematic reviewLow qualityRelated question
59 people2024
about 1.7% of cases turned cancerous, and lovastatin/cholesterol cream looked promising as treatment
Who was studied
people with a rare skin condition called porokeratosis ptychotropica, median age 49
What they received
various treatments tried, including topical lovastatin/cholesterol cream
Compared with
no direct comparator, review of reported cases
Main outcome
risk of the condition turning into skin cancer and treatment effectiveness
Quality
it pools rare case reports on an uncommon condition, which carries a high risk of bias and can't be weighed like a controlled study.
Limitations
abstract notes significant bias in estimating rare occurrences in rare diseases, and best treatment remains uncertain
Taken word for word from the abstract
- n A total of 59 cases of porokeratosis ptychotropica have been reported
- population The median age of patients affected with porokeratosis ptychotropica was 49 years.
- intervention the use of topical lovastatin/cholesterol cream appears promising
- primaryOutcome The risk of malignant transformation in porokeratosis ptychotropica is approximately 1.7%
- result The risk of malignant transformation in porokeratosis ptychotropica is approximately 1.7% but there is significant bias in estimating rare occurrences in rare diseases.
- comparator This study aimed to characterize the worldwide distribution, epidemiology, clinical features, and treatments attempted for all reported cases of porokeratosis ptychotropica.
Acta Derm Venereol · PMID 39387668 · Read it on PubMed ↗
Martora et al. 2024
Hidradenitis Suppurativa in Elderly Patients: Clinical and Therapeutical Outcomes-A Review of the Literature
Review of HS treatment in elderly.Narrative reviewLow qualityRelated question
size not given2024
the abstract discusses treatment considerations and challenges but does not report a specific outcome result
Who was studied
elderly patients with hidradenitis suppurativa
What they received
treatments for hidradenitis suppurativa including antibiotics and biologic drugs
Quality
This is a narrative literature review without original data or statistical results, so it cannot show whether treatments work.
Limitations
No original patient data, no outcome measures, and focuses specifically on elderly patients rather than the general population asking about this condition.
Taken word for word from the abstract
- population The management of hidradenitis suppurativa (HS) in elderly patients presents unique challenges due to its chronic inflammatory nature, heterogeneous clinical presentation and comorbidities.
- population elderly patients may exhibit atypical features such as the involvement of the neck, mammary area and gluteal region
- intervention While systemic antibiotics remain a mainstay of HS treatment, biologic agents such as TNFα inhibitors and secukinumab offer promising options for refractory cases.
- result their safety and efficacy in elderly patients, particularly those with multiple comorbidities, require careful consideration
Medicina (Kaunas) · PMID 39336506 · Read it on PubMed ↗
Yamanaka-Takaichi et al. 2025
Differentiating clinical characteristics of perianal inflammatory bowel disease from perianal hidradenitis suppurativa
Different skin clues separate acne-like bumps from bowel disease.RetrospectiveLow qualityRelated question
263 people2025
HS was linked to tunnels and comedones (whiteheads/blackheads) and lesions near the armpits and groin, while IBD was linked to fistulas, abscesses, ulcers, and lesions on the buttocks and perineum
Who was studied
patients with perianal skin problems evaluated at a clinic, some with hidradenitis suppurativa, some with inflammatory bowel disease, some with both
What they received
having hidradenitis suppurativa (HS) type perianal lesions
Compared with
having inflammatory bowel disease (IBD) related perianal fistulas
Main outcome
identifying which clinical features tell apart HS from IBD-related perianal disease
Quality
it is a retrospective review from patient records at one clinic, which can miss or misclassify details and doesn't test a treatment.
Limitations
Retrospective chart review from a single academic center, so findings may not generalize and causal relationships can't be confirmed.
Taken word for word from the abstract
- n A total of 263 patients were included (98 with HS, 100 with IBD, and 65 with both IBD and HS).
- population patients with perianal disease evaluated at Mayo Clinic from January 1, 1998, through July 31, 2021
- intervention Patients with HS had a higher mean body mass index, a higher smoking rate, and more commonly showed cutaneous manifestations of tunnels and comedones
- comparator fistulas, abscesses, induration, anal tags, ulcers, and anal fissures were more common in patients with IBD
- primaryOutcome random forests were used to select the 15 most important clinical features to construct the diagnostic prediction model to distinguish perianal HS from fistulizing perianal IBD
- result patients with IBD often had lesions in the buttocks and perineum, while those with HS had additional lesions in the axillae and groin
Int J Dermatol · PMID 39306801 · Read it on PubMed ↗
Lai et al. 2024
Adopting adalimumab combined surgery in the management of moderate to severe hidradenitis suppurativa: Experience from a single medical center in southern Taiwan
Biologic drug plus surgery improved severe boils.RetrospectiveLow qualityRelated question
19 people2024
68.4% of patients improved, 15.8% stayed stable, 15.8% did not respond as expected, with no severe side effects
Who was studied
Adults with moderate to severe hidradenitis suppurativa (a chronic inflammatory skin condition often affecting the buttocks and groin)
What they received
Adalimumab (a biologic injection) combined with surgical excision
Compared with
No control group; outcomes compared to expected treatment response
Main outcome
Clinical improvement after treatment
Quality
This was a retrospective chart review of a small group with no comparison group, so it can't prove the treatment caused the improvement.
Limitations
Retrospective nature and lack of a control group
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic inflammatory disorder primarily affecting the intertriginous and anogenital regions.
- n Nineteen patients received excision with pre-surgical adalimumab; their average age at diagnosis was 31.1, with a gender ratio of 5.3:1.
- intervention Nineteen patients received excision with pre-surgical adalimumab
- comparator our study was limited by its retrospective nature and the lack of a control group
- primaryOutcome investigated clinical features and treatment response
- result Adalimumab and surgery combined yielded a 68.4% improvement rate, while 15.8% remained stable and 15.8% did not respond as expected.
- limitations our study was limited by its retrospective nature and the lack of a control group
J Dermatol · PMID 39032108 · Read it on PubMed ↗
Brusasco et al. 2024
A Case of Noonan Syndrome and Kyrle's Disease: Coincidence or Causality?
Rare condition, cleared by light therapy.Case seriesVery low qualityRelated question
1 people2024
Complete and long-lasting resolution of symptoms, though with some residual atrophic scarring
Who was studied
A 39-year-old woman with Noonan Syndrome who developed itchy bump-like skin lesions
What they received
Narrowband UVB phototherapy
Compared with
No comparison treatment
Main outcome
Resolution of the itchy perforating skin lesions (Kyrle's disease)
Quality
This is a single case report of one rare patient, so it cannot reliably show what causes or treats typical buttock pimples.
Limitations
Single patient case report; rare condition (Kyrle's disease) linked to Noonan Syndrome, not typical acne or folliculitis; no control group; no clear causal mechanism established.
Taken word for word from the abstract
- n A 39-year-old Caucasian woman affected by Noonan Syndrome (NS) mutated in RAF1 was referred to us with itchy lesions on her limbs that had appeared two months earlier.
- population A 39-year-old Caucasian woman affected by Noonan Syndrome (NS) mutated in RAF1 was referred to us with itchy lesions on her limbs that had appeared two months earlier.
- intervention The patient underwent narrowband UVB (NB-UVB) phototherapy with residual atrophic scars (Figure 1, c-d) but with complete and long-lasting resolution of symptoms as well.
- comparator The patient underwent narrowband UVB (NB-UVB) phototherapy with residual atrophic scars (Figure 1, c-d) but with complete and long-lasting resolution of symptoms as well.
- primaryOutcome with complete and long-lasting resolution of symptoms as well
- result The patient underwent narrowband UVB (NB-UVB) phototherapy with residual atrophic scars (Figure 1, c-d) but with complete and long-lasting resolution of symptoms as well.
Acta Dermatovenerol Croat · PMID 38946190 · Read it on PubMed ↗
Wong et al. 2024
A review of surgical and reconstructive techniques for hidradenitis suppurativa
Surgery works best for this skin condition.Narrative reviewLow qualityRelated question
size not given2024
surgery, especially wide excision, gave the best long-lasting control and healing compared to other treatments, though best reconstruction method is still debated
Who was studied
people with hidradenitis suppurativa (chronic inflammatory skin condition affecting armpit, groin, buttock areas)
What they received
surgical treatment (excision, laser, deroofing) and reconstructive techniques
Compared with
medical/non-surgical management
Main outcome
long-term control and healing of skin lesions
Quality
this is a narrative review summarizing existing surgical techniques without new patient data or controlled comparisons.
Limitations
review does not report original patient numbers or controlled trial data; focuses on surgical technique discussion rather than diagnosing causes of buttock pimples.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is an inflammatory follicular dermatological condition that typically affects the intertriginous and anogenital regions of the apocrine gland-bearing skin.
- intervention surgical therapy, which is the gold standard of treatment for HS, has proven to be the most effective treatment
- comparator While medical treatments are recommended for this multimodal disease
- primaryOutcome it provides long-lasting local disease control, reduces the recurrence of lesions, and ensures complete healing of lesions
- result Among these surgical procedures, wide surgical excision is the best option since it can eradicate all the affected lesions.
Arch Dermatol Res · PMID 38796609 · Read it on PubMed ↗
Erol Mart et al. 2024
Demographic and Clinical Features and Factors Affecting the Quality of Life of Patients With Hidradenitis Suppurativa: A Cross-sectional Study
Severe cases hurt quality of life moreRetrospectiveLow qualityRelated question
176 people2024
quality of life was worse in patients with more advanced disease stage, lesions in the buttock/leg area, and more affected body areas
Who was studied
adults aged 18 to 65 with hidradenitis suppurativa
What they received
none - observational study examining demographic and clinical characteristics
Compared with
none - no treatment comparison, patients compared by disease severity and location
Main outcome
quality of life as measured by the Dermatology Life Quality Index
Quality
this is a cross-sectional observational study without a control or follow-up, so it can only show associations, not prove what causes the condition or how to treat it.
Limitations
abstract does not describe study limitations such as recall bias, generalizability, or confounding
Taken word for word from the abstract
- n One hundred seventy-six patients with HS aged between 18 and 65 years were included in the study.
- population One hundred seventy-six patients with HS aged between 18 and 65 years were included in the study.
- primaryOutcome The Dermatology Life Quality Index (DLQI) was used to evaluate QoL.
- result Mean DLQI scores were significantly higher in patients with advanced Hurley stages, lesions in the gluteal region and legs, and with more than 2 affected areas ( p < .001).
- intervention The patients' demographic and clinical characteristics, treatments, and comorbidities were recorded.
- comparator Correlations between patient-reported treatment outcomes and clinical characteristics of the patients were assessed.
Dermatol Surg · PMID 38563434 · Read it on PubMed ↗
Brusasco et al. 2023
A Case of Noonan Syndrome and Kyrle Disease: Casualty or Causality?
Rare condition, not typical acne.Case seriesVery low qualityRelated question
1 people2023
the lesions completely and lastingly cleared after treatment, though some scarring remained
Who was studied
39-year-old woman with Noonan Syndrome who developed itchy skin lesions on her arms and legs
What they received
narrowband UVB phototherapy for the skin lesions
Main outcome
resolution of the itchy skin lesions
Quality
This is a single patient case report, so it cannot show whether this applies to other people or to typical buttock pimples.
Limitations
Only one patient was described, the condition (Kyrle disease) is rare and linked to other illnesses, and the lesions were on the limbs rather than the buttocks.
Taken word for word from the abstract
- population A 39-year-old Caucasian woman affected by Noonan Syndrome (NS) mutated in RAF1 was referred to us with itchy lesions on her limbs that had appeared two months earlier.
- intervention The patient underwent narrowband UVB (NB-UVB) phototherapy
- result with residual atrophic scars (Figure 1, c-d), but with a complete and long-lasting resolution of symptoms.
- primaryOutcome complete and long-lasting resolution of symptoms
- n A 39-year-old Caucasian woman
Acta Dermatovenerol Croat · PMID 38439730 · Read it on PubMed ↗
Zundell et al. 2024
A New Tool to Improve Communication Between Hidradenitis Suppurativa Patients and Health Care Providers
Communication tool improved patient-doctor visits.Case seriesLow qualityRelated question
30 people9-month long period
Higher questionnaire helpfulness ratings were linked to better overall clinical experience ratings
Who was studied
People with hidradenitis suppurativa (HS) seen at a dermatology clinic
What they received
A new patient questionnaire ('Shine a Light on HS' as modified by IDEOM) completed before the doctor visit
Compared with
No comparison group; patients rated the tool after using it
Main outcome
Patient-rated helpfulness of the questionnaire and overall quality of the clinical visit
Quality
Small single-site study of 30 patients with no comparison group, relying on self-reported ratings.
Limitations
Single site, small sample (n=30), no control group, self-reported outcome scales.
Taken word for word from the abstract
- n The analysis cohort (n=30) consisted of a racially and ethnically diverse patient population.
- population Patients with HS presenting to Mount Sinai Union Square over a 9-month long period
- intervention the Shine a Light on HS as Modified by the IDEOM HS Workgroup Questionnaire
- comparator After the visit, patients rated their overall clinical experience and the helpfulness of the survey on a 5-point scale.
- primaryOutcome the mean helpfulness rating was 3.1 (SD=1), and the mean clinical experience rating was 3.5 (SD=0.78)
- result There was a positive correlation between survey helpfulness and overall clinical experience and a moderately strong relationship by linear regression analysis (r=0.73, R2=0.53).
J Drugs Dermatol · PMID 38306140 · Read it on PubMed ↗
Greenzaid et al. 2023
Keratosis Pilaris: Treatment Practices of Board-Certified Dermatologists
Bumps often return after treatment.Case seriesLow qualityRelated question
size not giventhree months
Lactic acid was the most common first choice, laser therapy was rarely used, and over 60% saw bumps return within three months of stopping salicylic acid or moisturizer treatment
Who was studied
board-certified dermatologists treating keratosis pilaris (bumps often on buttocks)
What they received
topical treatments such as lactic acid and salicylic acid, plus laser therapy
Compared with
different topical and laser treatment options compared to each other
Main outcome
which treatments dermatologists use most and how well they work
Quality
This is just a survey of doctors' opinions and habits, not a controlled study testing whether treatments actually work.
Limitations
Based on a survey of dermatologists' reported practices and perceptions rather than measured patient outcomes, with no control group.
Taken word for word from the abstract
- population Keratosis pilaris (KP) is a chronic disorder of follicular hyperkeratinization and perifollicular erythema with lesions affecting the extensor surfaces of arms, upper legs, and buttocks
- intervention topical lactic acid is the most used first-line therapy for KP (43.63% of survey respondents), followed by salicylic acid (20.72%)
- comparator which topical treatments dermatologists utilize the most
- primaryOutcome to determine which topical treatments dermatologists utilize the most, the duration of therapy needed with various treatment modalities, and the effectiveness of topical and laser therapy for treating KP
- result over 60% of respondents found recurrence of KP lesions within three months of stopping salicylic acid treatment and OTC moisturizer treatment
- followUp recurrence of KP lesions within three months of stopping salicylic acid treatment and OTC moisturizer treatment
J Drugs Dermatol · PMID 37801530 · Read it on PubMed ↗
Riera-Martí et al. 2024
Gluteal Hidradenitis Suppurativa: Analysis of 83 Patients
Describes two subtypes of gluteal boils.RetrospectiveLow qualityRelated question
83 people2024
gluteal patients split into two distinct clinical subtypes, with differences in age, sex and lesion type compared to other hidradenitis suppurativa patients
Who was studied
patients with gluteal hidradenitis suppurativa (boil-like skin disease)
Compared with
compared gluteal-phenotype patients to the rest of the hidradenitis suppurativa patient group
Main outcome
clinical characteristics and subtypes of gluteal hidradenitis suppurativa
Quality
this was a small, retrospective study from only two hospitals looking at classification, not treatment effectiveness.
Limitations
retrospective nature, bicentric design, and small sample size
Taken word for word from the abstract
- n We designed a bicentric study gathering all LC3 patients (n=83) from two hospitals.
- population We designed a bicentric study gathering all LC3 patients (n=83) from two hospitals.
- comparator We conducted a two-step cluster analysis among them and also compared their characteristics with the rest of the HS patients (n=661).
- primaryOutcome To improve the classification of the gluteal phenotype (LC3) patients given their diverse lesion types and differences in clinical profile.
- result The analysis of LC3 patients yielded two clusters: cluster 1 (38.3%) included elderly female patients, with later diagnosis of the disease and more sinus tracts; cluster 2 (61.7%) encompassed more men with earlier disease onset and more nodules and folliculitis lesions.
- limitations The study's limitations include its retrospective nature, bicentric design, and small sample size.
Actas Dermosifiliogr · PMID 37797882 · Read it on PubMed ↗
Krueger et al. 2024
Hidradenitis suppurativa: new insights into disease mechanisms and an evolving treatment landscape
Chronic inflammatory skin disease, not simple acne.Narrative reviewLow qualityRelated question
size not given2024
review states HS is driven by immune pathways (TNF-alpha and IL-17) and causes chronic bumps and abscesses in areas like the armpits, groin and buttocks
Who was studied
people with hidradenitis suppurativa (also called acne inversa), a chronic skin condition
What they received
various treatments including topical medications, antibiotics, retinoids, hormonal therapy, biologics and surgery
Compared with
no specific comparator described
Quality
this is a general review summarizing current understanding and treatments, not a study testing a specific treatment's effect.
Limitations
abstract does not describe original study methods, population size, or statistical results; it is a review of a specific diagnosed disease rather than general pimples.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic disabling and debilitating inflammatory disease with a high unmet medical need.
- intervention treatment options include topical medications; systemic therapies, including repeated and/or rotational courses of systemic antibiotics, retinoids and hormonal therapies; and various surgical procedures
- result HS is characterized by persistent, painful cutaneous nodules, abscesses and draining tunnels commonly affecting the axillary, anogenital, inguinal and perianal/gluteal areas
- result the tumour necrosis factor (TNF)-α and interleukin (IL)-17 pathways have an important role, involving multiple cytokines
- comparator The anti-TNF-α antibody adalimumab is currently the only biologic approved by both the US Food and Drug Administration and the European Medicines Agency for HS
Br J Dermatol · PMID 37715694 · Read it on PubMed ↗
Witte et al. 2023
Targeting Metabolic Syndrome in Hidradenitis Suppurativa by Phytochemicals as a Potential Complementary Therapeutic Strategy
Possible link to metabolic syndrome, not proven.Narrative reviewLow qualityRelated question
size not given2023
the review describes mechanisms and summarizes existing preclinical and trial data but does not report a direct result for hidradenitis suppurativa patients
Who was studied
people with hidradenitis suppurativa, a chronic skin disease causing painful lumps in the groin, buttocks, and underarms
What they received
plant-derived compounds (phytochemicals) aimed at improving metabolic syndrome
Compared with
not a controlled comparison; review discusses findings from other studies in healthy people and patients without hidradenitis suppurativa
Main outcome
whether phytochemicals could help metabolic syndrome in hidradenitis suppurativa patients
Quality
it is a narrative review that mostly discusses mechanisms and evidence from other conditions rather than testing a treatment directly in people with this skin problem
Limitations
abstract states results on phytochemicals come from preclinical studies and trials in healthy people or patients without hidradenitis suppurativa, not from patients with the condition itself
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterized by the appearance of painful inflamed nodules, abscesses, and pus-draining sinus tracts in the intertriginous skin of the groins, buttocks, and perianal and axillary regions.
- intervention evaluates the potential of phytomedical drug candidates to alleviate its components
- comparator the outcomes of respective randomized controlled clinical trials in healthy people and patients without HS are presented
- primaryOutcome evaluates the potential of phytomedical drug candidates to alleviate its components
- result the results from the preclinical studies with phytochemicals on MetS parameters are evaluated and the outcomes of respective randomized controlled clinical trials in healthy people and patients without HS are presented
- limitations the outcomes of respective randomized controlled clinical trials in healthy people and patients without HS are presented
Nutrients · PMID 37686829 · Read it on PubMed ↗
Aung et al. 2023
Scaly erythematous eruptions of intertriginous locations
Steroid cream cleared rash in one case.Case seriesVery low qualityRelated question
size not given4 weeks
Management with potent topical steroid and avoidance of inciting triggers offered resolution in 4 weeks in this case.
Who was studied
flaky erythematous eruptions in a female adult
What they received
potent topical steroid and avoidance of inciting triggers
Main outcome
resolution
Quality
this is a single patient case report, so it cannot show whether the treatment works in general.
Limitations
single case report with no control group, so findings may not generalize.
Taken word for word from the abstract
- population We here present a case of flaky erythematous eruptions in a female adult
- intervention Management with potent topical steroid and avoidance of inciting triggers
- primaryOutcome offered resolution in 4 weeks in this case
- result Management with potent topical steroid and avoidance of inciting triggers offered resolution in 4 weeks in this case.
N Z Med J · PMID 37501251 · Read it on PubMed ↗
Mintoff et al. 2023
NCSTN In-Frame Deletion in Maltese Patients With Hidradenitis Suppurativa
Rare gene variant linked to unusual HS patternCase seriesLow qualityRelated question
113 people2023
The gene variant was found in about 12% of patients and was linked to earlier onset and an unusual pattern involving the scalp, neck, torso and elbow creases
Who was studied
Adults with hidradenitis suppurativa (a condition causing lumps and boils in areas like the buttocks, groin, armpits) in Malta
What they received
Genetic testing for a specific NCSTN gene deletion
Compared with
Patients with hidradenitis suppurativa who did not carry the gene variant
Main outcome
How common the NCSTN gene variant is and whether it links to a distinct disease pattern
Quality
This is a single-center study of one ethnic population looking at genetics, not a treatment trial, so it can't tell us whether any intervention helps.
Limitations
Conducted in a single ethnic (Maltese) population at one reference center, so findings on this specific gene variant may not generalize, and the study does not address general causes or treatment of buttock pimples.
Taken word for word from the abstract
- n A total of 113 patients with HS (56 women [49.6%]) met the inclusion criteria and were enrolled in this study.
- population patients 18 years or older with a diagnosis of HS as defined by recurrent nodules, abscesses, and/or draining tunnels in typical (axilla, breast, groin, buttock, thighs, and inframammary folds) and less typical (scalp, ear pinnae, neck, arms, antecubital fossae) sites
- intervention targeted genetic analysis for an NCSTN deletion
- comparator The variant was not identified in an ethnically matched reference genomic data set of disease-free individuals.
- primaryOutcome To determine the prevalence of the NCSTN:c.671_682del variant and establish possible genotype-phenotype associations in the ethnically Maltese HS cohort.
- result The NCSTN variant was identified in the heterozygous state in 14 patients (12.4%) from 5 unrelated, nonconsanguineous families of Maltese ethnicity.
- result Variant carriers manifested HS symptoms earlier and were more likely to exhibit a distinctive HS phenotype, which was characterized by involvement of the scalp, neck, torso, and antecubital fossae.
JAMA Dermatol · PMID 37494055 · Read it on PubMed ↗
Fabian et al. 2023
Hidradenitis suppurativa. A case report
Severe case fixed with surgery.Case seriesVery low qualityRelated question
1 people2023
the case was successfully managed with combined surgical and conservative treatment
Who was studied
a 28-year-old man with advanced, persistent hidradenitis suppurativa
What they received
combined conservative and surgical treatment including wide excisions and flap reconstruction surgeries
Compared with
none
Main outcome
resolution of the disease/wound closure
Quality
this is a single patient case report, so it cannot show whether the treatment works in general.
Limitations
single case report with no comparison group; describes a severe surgical case, not typical mild buttock pimples.
Taken word for word from the abstract
- n a 28-year-old man
- population a 28-year-old man who presented with an advanced and persistent form of hidradenitis treated in a general surgery department
- intervention Solving the case combined conservative and surgical treatment (wide excisions, plasties with fasciocutaneous superior gluteal artery perforator flap, thoracodorsal artery perforator flap, free anterolateral thigh flap).
- comparator Solving the case combined conservative and surgical treatment
- primaryOutcome Solving the case combined conservative and surgical treatment
- result Solving the case combined conservative and surgical treatment (wide excisions, plasties with fasciocutaneous superior gluteal artery perforator flap, thoracodorsal artery perforator flap, free anterolateral thigh flap).
Ann Ital Chir · PMID 37226509 · Read it on PubMed ↗
Smiley et al. 2023
Positive Predictive Value of Diagnosis Codes for Hidradenitis Suppurativa and Cutaneous Abscess
Did not study causes of buttock pimples.RetrospectiveLow qualityRelated question
200 people2023
the diagnosis-code algorithm correctly identified hidradenitis suppurativa 88% of the time and cutaneous abscess 75% of the time, compared to doctor chart review
Who was studied
patients with diagnosis codes for hidradenitis suppurativa or cutaneous abscess in the buttock, groin, axilla, or perineum region
What they received
a diagnosis-code based algorithm to identify hidradenitis suppurativa or cutaneous abscess cases in a health system database
Compared with
dermatologist chart review as the gold-standard diagnosis
Main outcome
accuracy (positive predictive value) of diagnosis codes for correctly identifying hidradenitis suppurativa or cutaneous abscess
Quality
this is a small retrospective check of medical record coding accuracy, not a study of causes or treatments, so it offers very little direct evidence for the actual question.
Limitations
abstract does not describe how records were selected beyond the coding algorithm, nor any info on causes or treatment of buttock pimples.
Taken word for word from the abstract
- n Among 100 HS patients, median age
- n Median age among 100 CA patients
- population identify HS and cutaneous abscess (CA) case cohorts
- intervention a case-finding algorithm for HS which included the presence of at least one diagnosis code for HS and no diagnosis codes for CA of the axilla, groin, perineum, or buttock at any time
- comparator the dermatologist's chart-based adjudication as the reference standard
- primaryOutcome The positive predictive values (PPVs) of the ICD code-based case definitions were calculated
- result The PPVs of the ICD-based case-finding algorithms for HS and CA were 88% (95% CI 81.6-94.4%) and 75.0% (95% CI 66.5-83.5%), respectively.
Dermatology · PMID 36538899 · Read it on PubMed ↗
de Oliveira et al. 2022
Transcriptome Meta-Analysis Confirms the Hidradenitis Suppurativa Pathogenic Triad: Upregulated Inflammation, Altered Epithelial Organization, and Dysregulated Metabolic Signaling
Inflammation and skin-barrier genes altered in HSMeta-analysisLow qualityRelated question
size not given2022
confirmed three combined problems: too much inflammation, disrupted skin-barrier genes, and abnormal metabolism signaling
Who was studied
people with hidradenitis suppurativa, a skin condition causing painful lumps in areas like the armpits, groin, and buttocks
What they received
gene-expression (RNA-sequencing) meta-analysis of HS-affected skin
Main outcome
patterns of gene activity underlying the disease
Quality
This is a lab-based gene study of a different, more severe condition (hidradenitis suppurativa) rather than ordinary pimples, and it does not report how many patients were studied.
Limitations
No patient numbers given, no clinical outcomes measured, and findings are specific to hidradenitis suppurativa rather than common acne/pimples.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is an inflammatory skin condition clinically characterized by recurrent painful deep-seated nodules, abscesses, and sinus tracks in areas bearing apocrine glands, such as axillae, breasts, groins, and buttocks.
- intervention we performed a meta-analysis, set analysis, and a variant calling on selected RNA-Sequencing (RNA-Seq) studies on HS skin
- primaryOutcome Our findings corroborate the HS triad composed of upregulated inflammation, altered epithelial differentiation, and dysregulated metabolism signaling.
- result Our findings corroborate the HS triad composed of upregulated inflammation, altered epithelial differentiation, and dysregulated metabolism signaling.
Biomolecules · PMID 36291580 · Read it on PubMed ↗
Świerczewska et al. 2022
Immunomodulatory Drugs in the Treatment of Hidradenitis Suppurativa-Possibilities and Limitations
Reviews drugs for a different skin disease.Narrative reviewVery low qualityRelated question
size not given2022
The abstract does not report specific outcome data; it is a review describing current and emerging drug targets rather than reporting results of a particular treatment trial.
Who was studied
people with hidradenitis suppurativa (acne inversa), a skin condition affecting skin folds including buttock/groin areas
What they received
immunomodulatory drugs and biologics (such as adalimumab) targeting the immune pathways of the disease
Main outcome
effectiveness of drugs in treating hidradenitis suppurativa
Quality
This is a narrative review describing drug targets and mechanisms without presenting original trial data or outcomes.
Limitations
The abstract does not report specific patient numbers, trial results, or direct comparisons; it is a review of molecular mechanisms and treatment possibilities rather than a study of causes of butt pimples.
Taken word for word from the abstract
- population Hidradenitis suppurativa, also known as acne inversa, is a chronic, progressive, debilitating, recurrent inflammatory skin disease characterized by the occurrence of very severe, persistent, painful nodules, abscesses, and fistulas, most commonly found in the skin folds of the axilla, groin, gluteal, and perianal areas.
- intervention The safety and efficacy of adalimumab, still the only U.S. Food and Drug Administration approved biologic in the hidradenitis suppurativa treatment, paved the way for new drugs to be compared with it.
- primaryOutcome The aim of the article was to present the current and future targets of acne inversa treatment, simultaneously providing insights into the molecular pathomechanisms of the disease.
- result Several more drugs with new immunological targets are currently under investigation for the treatment of acne inversa.
Int J Mol Sci · PMID 36077114 · Read it on PubMed ↗
Witte et al. 2022
Phytotherapeuthics Affecting the IL-1/IL-17/G-CSF Axis: A Complementary Treatment Option for Hidradenitis Suppurativa?
Proposes herbal treatment idea, no results yetNarrative reviewVery low qualityRelated question
size not given2022
the review discusses and evaluates immune pathway as a possible target for plant-based treatment, but does not report trial results
Who was studied
people with hidradenitis suppurativa, a chronic skin disease causing painful lesions in armpit, groin, buttock and genital areas
What they received
plant-based (phytomedical) drugs targeting certain immune signals
Compared with
current standard treatments (antibiotics, surgery, TNF-alpha blockers)
Main outcome
whether plant-based drugs could help treat hidradenitis suppurativa by targeting specific immune pathways
Quality
This is a conceptual review describing a disease pathway and proposing a treatment idea, with no original patient data or trial results.
Limitations
No original research data, patient numbers, or outcome measurements are reported; this is a theoretical/review discussion, and hidradenitis suppurativa is a distinct, more severe condition than ordinary pimples.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS; also designated as acne inversa) is a chronic inflammatory disease characterized by painful skin lesions that occur in the axillary, inguinal, gluteal and perianal areas of the body.
- intervention phytomedical drugs display potent immunoregulatory properties and have been suggested as complementary therapy in several chronic disorders
- comparator Therapeutic options for HS are limited, comprising long-term antibiotic treatment, the surgical removal of affected skin areas, and neutralization of TNF-α, the only approved systemic treatment.
- primaryOutcome we describe the IL-1/IL-17/G-CSF axis and evaluate it as potential target for an integrated phytomedical treatment of HS
- result In this review, we describe the IL-1/IL-17/G-CSF axis and evaluate it as potential target for an integrated phytomedical treatment of HS.
Int J Mol Sci · PMID 36012322 · Read it on PubMed ↗
Johnston et al. 2022
Practical Guidelines for Managing Patients With Hidradenitis Suppurativa: An Update
Guideline for diagnosing and managing this skin condition.Narrative reviewVery low qualityRelated question
size not given2022
the abstract does not report outcome data, only that the guideline aims to improve diagnosis and management
Who was studied
people with hidradenitis suppurativa, a chronic inflammatory skin condition affecting armpits, groin, under breasts, and buttock areas
What they received
a structured approach to diagnosing and managing the condition, including a medical record template
Main outcome
improving diagnosis and quality of care for the condition
Quality
this is an expert guideline/review, not a study testing a treatment, so it provides no data on whether any intervention works
Limitations
abstract does not describe any treatment outcomes, patient numbers, or comparative data; it is a practical guideline document
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease that is characterized by the formation of comedones, papules, nodules, abscesses and sinus tracts in the axillary, inframammary, groin, and gluteal areas.
- intervention A sample electronic medical record template for HS management was developed by the Canadian Hidradenitis Suppurativa Foundation Executive Board and is intended for use in clinical settings.
- primaryOutcome The aim of this review is to provide a practical approach for all healthcare providers to diagnose and manage HS and its associated comorbidities.
- result This will help to increase collaboration between primary healthcare providers, dermatologists, and other medical specialists and ultimately improve the quality of care that HS patients receive.
J Cutan Med Surg · PMID 36000460 · Read it on PubMed ↗
van Straalen et al. 2022
Insights into hidradenitis suppurativa
Explains why these bumps form, no treatment testedNarrative reviewLow qualityRelated question
size not given2022
The abstract describes the biology and risk factors of hidradenitis suppurativa rather than reporting a treatment trial result
Who was studied
people with hidradenitis suppurativa, a chronic skin condition affecting underarms, groin, and buttock areas
Quality
this is a narrative review summarizing disease background, not a study testing any treatment, so it offers no outcome data to weigh
Limitations
The abstract does not test any intervention or report trial outcomes; it is a descriptive/background review
Taken word for word from the abstract
- population Characteristic lesions such as inflammatory nodules, abscesses, and sinus tracts develop in the axillae, inguinal, and gluteal areas, typically during or after puberty.
- result HS is considered to arise from an intrinsic defect within the hair follicle, leading to follicular plugging, cyst formation, and subsequent rupture that in turn induce an acute inflammatory response characterized by elevated levels of IL-1β, IL-17, and TNF.
J Allergy Clin Immunol · PMID 35189127 · Read it on PubMed ↗
Lewandowski et al. 2022
Hidradenitis suppurativa: a review of current treatment options
No single treatment works well.Narrative reviewLow qualityRelated question
size not given2022
no single treatment works well for everyone; best results need a multidisciplinary approach
Who was studied
people with hidradenitis suppurativa (a chronic skin disease with painful lumps, often in skin folds including the buttock/groin area)
What they received
various treatments for hidradenitis suppurativa
Compared with
different treatment options compared to each other
Main outcome
effectiveness of treatment / disease management
Quality
this is a narrative review summarizing treatment options, not a study testing a specific treatment, so it can't show whether any one approach works.
Limitations
no original data, no quantitative results, and it is about treating an existing diagnosed disease rather than explaining why pimples occur in the first place
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic, progressive, debilitating, recurrent inflammatory skin disease characterized by the occurrence of very severe, persistent, painful nodules, abscesses, and fistulas, most commonly found in the skin folds of the axilla, groin, gluteal, and perianal areas.
- intervention This article aims to provide updates on the current treatment options of acne inversa to raise awareness and improve the management of the disease.
- comparator Regardless of the fact that there are multiple treatment options for HS, no uniformly effective therapy has been found.
- primaryOutcome the selection of the appropriate therapy is extremely important in these patients
- result Regardless of the fact that there are multiple treatment options for HS, no uniformly effective therapy has been found. All the guidelines underline the need for a multidisciplinary approach to the disease, which enables providers to create the right management of HS.
Int J Dermatol · PMID 35128643 · Read it on PubMed ↗
Barmatz et al. 2022
The Bacteriology of Skin Lesions in Patients with Hidradenitis Suppurativa Is Associated with Previous Antibiotic Treatment in the Community Setting: A Referral Center Experience
Prior antibiotics shifted lesion bacteria.RetrospectiveLow qualityRelated question
97 people2022
patients previously treated with antibiotics had more gram-negative bacteria and more types of bacteria per lesion than untreated patients
Who was studied
patients with hidradenitis suppurativa (a chronic skin disease with nodules and abscesses, often in genitalia, buttocks/groin, and underarms)
What they received
previous antibiotic treatment in the community before referral
Compared with
patients not previously treated with antibiotics
Main outcome
type of bacteria found in skin lesion cultures
Quality
this is a retrospective, uncontrolled study of bacterial cultures from one referral clinic, not a trial testing whether any treatment reduces pimples or lesions.
Limitations
Retrospective, single referral-center cohort; antibiotic use was nonstandardized and not randomized; no comparison to healthy skin or control group without HS.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic skin disease characterized by inflammatory nodules and abscesses
- population the most active lesions concentrated in the genitalia, gluteal/perineal area, and axilla
- intervention Seventy-eight patients (80.4%) had been treated in the community setting prior to referral with a median (range) of 2 (1-8) lines of antibiotics
- comparator Compared to the previously untreated patients
- primaryOutcome The correlation between the location of the skin lesion and the bacteriologic profile was analyzed, and the effects of previous antibiotic treatment on the bacteriologic profile of the lesions and susceptibility patterns of the cultured bacteria were evaluated.
- result cultures of lesions from the previously treated patients yielded a higher percentage of gram-negative Enterobacterales (the most common isolates in this group) (31.3% vs. 10.3%) and a significantly higher median number of isolates per culture (2 vs. 1, p < 0.0001)
- n Pus (or tissue) from inflammatory lesions of 97 patients with HS was cultured.
Dermatology · PMID 35086093 · Read it on PubMed ↗
Hayashi et al. 2022
Real-world safety and effectiveness of adalimumab in patients with hidradenitis suppurativa: 12-week interim analysis of post-marketing surveillance in Japan
Reduced symptoms with adalimumab treatment.Prospective cohortLow qualityRelated question
83 people12 weeks
at 12 weeks, 57.4% of patients had a clinical response, with significant reductions in skin pain, quality-of-life impact, and inflammation markers; no serious infections and no new safety concerns
Who was studied
Japanese patients with hidradenitis suppurativa, a chronic painful skin disease causing abscesses and nodules, often affecting buttocks and groin
What they received
adalimumab (anti-TNF-alpha injection) given under the skin
Compared with
before-and-after comparison, no control group
Main outcome
safety of adalimumab in routine clinical practice
Quality
This was an open-label, real-world observational study without a comparison group, so improvement cannot be clearly separated from natural disease fluctuation.
Limitations
Open-label, observational, post-marketing study with no control group; this is an interim 12-week analysis.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a painful chronic skin disease characterized by abscesses, nodules, and tunnels in the skin.
- population The most common affected sites were the axilla (60.2%), buttocks (59.0%), and the inguinal and femoral regions (47.0%).
- intervention Patients with HS were treated with s.c. doses of adalimumab according to the dosage described in the package insert.
- comparator This multicenter, open-label, post-marketing, observational study
- primaryOutcome The primary end-point was safety (data cut-off, December 2020).
- result At week 12, 57.4% of patients achieved HiSCR, and significant reductions from baseline in skin pain, DLQI (both p < 0.0001), and CRP (p = 0.0029) were observed.
- n A total of 84 eligible patients from 65 sites were enrolled; 83 patients were included in this analysis.
J Dermatol · PMID 35040156 · Read it on PubMed ↗
Chu et al. 2021
Hidradenitis suppurativa: Disease pathophysiology and sex hormones
Butt pimples may be hidradenitis suppurativa, more common in men.Narrative reviewVery low qualityRelated question
size not given2021
men were more likely to have buttock lesions while women were more likely to have armpit, groin, and under-breast lesions, and disease severity varied with menstruation, pregnancy, and menopause
Who was studied
people with hidradenitis suppurativa, a chronic inflammatory skin disease
What they received
review of disease pathophysiology and sex hormone effects (no specific treatment tested)
Compared with
comparison between men and women with hidradenitis suppurativa
Main outcome
patterns of disease location and severity by sex and hormonal status
Quality
this is a descriptive review summarizing existing knowledge rather than a study that tested a treatment or measured a specific outcome.
Limitations
abstract does not describe study methods, sample size, or how sex-difference claims were derived; it is a narrative summary, not original controlled research.
Taken word for word from the abstract
- population Hidradenitis suppurativa is a cutaneous chronic inflammatory disease that is estimated to affect about 1% of the population
- intervention This review introduces the skin appendages and pathophysiology of hidradenitis suppurativa and then focuses on the sex difference and the effects of sex hormones on hidradenitis suppurativa and current hormone-associated treatments.
- comparator Men are prone to have buttock involvement while women are prone to have axillary, groins, and submammary lesions.
- primaryOutcome the phenotypes are different among men and women with hidradenitis suppurativa
- result Men are prone to have buttock involvement while women are prone to have axillary, groins, and submammary lesions.
- result The disease severity can be affected by menstruation, pregnancy, and menopause.
Chin J Physiol · PMID 34975118 · Read it on PubMed ↗
Friedman et al. 2021
Optimizing Outcomes With the 1550/1927 nm Dual Wavelength Non-Ablative Fractional Laser: Experienced User Recommendations
Not relevant to buttock pimple causes.GuidelineVery low qualityRelated question
8 people2021
survey of experienced users suggested the laser can treat many skin issues including acne or surgical scarring, and can be used on areas including the buttocks
Who was studied
dermatologists experienced with a specific laser device, not patients with buttock acne
What they received
1550 nm/1927 nm dual wavelength non-ablative fractional laser
Compared with
none reported
Main outcome
expert recommendations and best practices for using the laser device
Quality
this is a small expert opinion survey about laser technique, not a study testing why pimples occur on the buttocks or how to treat them.
Limitations
small survey of only 8 dermatologists, opinion-based position paper, not a controlled study, and does not address causes of buttock pimples
Taken word for word from the abstract
- n sent to eight (8) US board certified dermatologists
- population An online survey addressing use of a 1550 nm /1927 nm dual wavelength, non-ablative, fractional laser was sent to eight (8) US board certified dermatologists with extensive experience in the use of the device.
- intervention 1550 nm /1927 nm dual wavelength, non-ablative, fractional laser
- comparator The survey included 39 questions, addressing experience, best practices and recommendations for use.
- primaryOutcome This position paper provides practical real-world guidelines resulting from a small survey of experienced users
- result It can be used on both facial and non-facial areas, including neck, chest, hands, arms, abdomen, legs, and buttocks.
J Drugs Dermatol · PMID 34784135 · Read it on PubMed ↗
Lovrić et al. 2021
Two Cases of Hidradenitis Suppurativa Treated with Adalimumab at the Department of Dermatology and Venereology, Clinical Hospital Mostar
Boils and skin lesions improved with treatment.Case seriesVery low qualityRelated question
2 people16 weeks
Both patients improved; one had unchanged Hurley stage but large drop in quality-of-life score, the other improved in both disease stage and quality of life
Who was studied
Adults with severe hidradenitis suppurativa (painful boils/nodules in skin fold areas including buttocks)
What they received
Adalimumab (biologic injection medication)
Compared with
No comparator (before-and-after treatment in same patients)
Main outcome
Improvement in disease severity scores and quality of life
Quality
Only two patients with no comparison group, so results could be due to chance or other factors rather than the drug.
Limitations
Only 2 patients, no control group, pre-existing conditions (diabetes, TB exposure) may have influenced outcomes.
Taken word for word from the abstract
- n The first male patient aged 59 years
- population multiple abscesses, fistulas, and nodules in the axillary, inguinal, perianal, gluteal, and intergluteal regions
- intervention prescribed adalimumab in doses of 80 mg initially, 40 mg ×2 on the first day and the day after that, then 80 mg after fifteen days followed by 40 mg every ten days
- comparator Our patients showed regression of lesions after sixteen weeks of biological therapy.
- primaryOutcome After 16 weeks of treatment with adalimumab, Hurley staging was II, PGA IV, DLQI 3.
- result After 16 weeks of treatment with adalimumab, Hurley staging was II, PGA staging was III, and DLQI index was 3.
Acta Dermatovenerol Croat · PMID 34477078 · Read it on PubMed ↗
Chandran et al. 2021
Hidradenitis suppurativa in South-East Asia and East Asia
Butt pimples common in East Asian HS patients.Narrative reviewLow quality
size not given2021
Buttock involvement is common in East Asian patients, with male predominance and metabolic comorbidities; family history is less common than in the West
Who was studied
people with hidradenitis suppurativa in South-East Asia and East Asia
Compared with
Western populations with hidradenitis suppurativa
Main outcome
clinical, environmental, physiological and genetic features of the condition
Quality
This is a narrative review describing patterns rather than testing a treatment or reporting a controlled study with numbers.
Limitations
No sample size, methodology, or statistical data given; appears to be a descriptive summary of regional patterns.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) in South-East Asia and East Asia
- result Involvement of the buttocks is common in East Asian patients, while the axillae are most commonly affected in South-East Asian patients.
- result A male predominance is present, which may be due to differences in smoking habits.
- result Metabolic comorbidities are prevalent in South-East Asian and East Asian HS patients.
- result A family history of HS is less common than noted in Western populations.
- primaryOutcome shows distinct clinical, environmental, physiological and likely genetic differences compared with the West
- comparator compared with the West
Exp Dermatol · PMID 34085331 · Read it on PubMed ↗
Gotesman et al. 2021
Hidradenitis suppurativa in East and Southeast Asian populations: a systematic review and meta-analysis
Many HS patients get buttock bumps too.Meta-analysisModerate qualityRelated question
30,125 people2021
About half of patients had lesions on the buttocks and about half in the armpits; most patients were male and few had a family history
Who was studied
People in East and Southeast Asia diagnosed with hidradenitis suppurativa (a chronic skin condition with inflamed bumps)
What they received
No treatment studied — this pooled data on where HS lesions occur on the body
Compared with
No comparator — descriptive analysis of lesion locations across combined studies
Main outcome
How often HS lesions occur in the armpit and buttock areas, and other patient characteristics
Quality
It pools many small observational studies which can vary a lot in quality, so the numbers are a reasonable estimate but not a strong test of cause or treatment.
Limitations
The abstract does not report specific limitations beyond being a meta-analysis of observational/case-series data with wide confidence intervals.
Taken word for word from the abstract
- n A total of 30,125 HS patients were included in the analysis.
- population English-language case-series, cross-sectional, observational, and randomized controlled trial studies investigating HS in East and Southeast Asian populations
- intervention Data on gender distribution, lesion distribution in the axilla and gluteal regions, and family history were extracted in duplicate.
- comparator A random effects model was used for the meta-analysis.
- primaryOutcome About half of Asian patients with HS develop lesions in the axilla (52%, 95% CI = 33-72%) and the buttocks (48%, 95% CI = 38-57%).
- result About half of Asian patients with HS develop lesions in the axilla (52%, 95% CI = 33-72%) and the buttocks (48%, 95% CI = 38-57%). Only a small subset had positive family history of HS (5%, 95% CI = 2-8%).
Int J Dermatol · PMID 34075575 · Read it on PubMed ↗
Garcias-Ladaria et al. 2021
Intralesional photodynamic therapy in hidradenitis suppurativa: Getting closer to the target
Treats a specific severe skin disease, not typical pimples.RetrospectiveLow qualityRelated question
42 people3 months
about 22% of lesions resolved and 62% improved at 3 months, but gluteal (buttock) location was linked to worse response; burns and abscesses were common side effects
Who was studied
patients with hidradenitis suppurativa (a chronic skin condition causing painful lumps, including in buttock/groin areas)
What they received
intralesional photodynamic therapy using a light-activated drug injected into lesions and then lasered
Compared with
no comparator group; outcomes measured before and after treatment in the same lesions
Main outcome
whether lesions resolved, improved, or showed no change 3 months after treatment
Quality
this was a retrospective, uncontrolled study of a specific severe skin disease, not a general explanation for pimples, so it offers weak and indirect evidence for the question asked.
Limitations
retrospective design, no control group, and gluteal lesions specifically responded less well to treatment
Taken word for word from the abstract
- population patients diagnosed with HS and treated with IL-PDT
- intervention 5-aminolevulinic acid (5ALA) in gel 2 % or solution 1 % was introduced in the lesion. After two hours, the lesion was intralesionally irradiated
- comparator The main outcome variable was the result (remission, improvement or no change) for each lesion 3 months after the therapy.
- primaryOutcome The main outcome variable was the result (remission, improvement or no change) for each lesion 3 months after the therapy.
- result At 3 months, 26 lesions (22.2 %) had resolved, 73 (62.4 %) had improved in size or symptoms, and 18 (15.4 %) experienced no change.
- result significant variables for no benefit were: a higher International Hidradenitis Suppurativa (IHS4) score, active smoking and gluteal and inguinal location
- n A total of 117 lesions (28 nodules and 89 fistulae) were treated in 42 patients.
Photodiagnosis Photodyn Ther · PMID 33992813 · Read it on PubMed ↗
Gáspár et al. 2022
Resource utilization, work productivity and costs in patients with hidradenitis suppurativa: a cost-of-illness study
Study measured costs, not causes.RetrospectiveLow qualityRelated question
200 people2022
average yearly cost per patient was about €6,791, driven mainly by lost work productivity and biologic drug costs
Who was studied
adults with hidradenitis suppurativa in Hungary
What they received
no treatment tested - researchers measured healthcare use, costs, and productivity loss
Compared with
no comparison group - single cohort cross-sectional analysis
Main outcome
total annual cost of illness (medical, non-medical, and work-related costs)
Quality
this is a cross-sectional cost survey of one disease group, not a trial testing a cause or treatment, so it cannot explain why the condition occurs.
Limitations
cross-sectional design limited to one country (Hungary), focused on economic burden rather than disease cause or treatment effect
Taken word for word from the abstract
- population among 200 adult HS patients
- intervention We evaluated direct medical (physician consultations, inpatient admissions, medical, and surgeries), direct non-medical (transportation and caregiving), and indirect costs (productivity loss).
- comparator A multicentre, cross-sectional cost-of-illness study was performed among 200 adult HS patients.
- primaryOutcome The mean annual cost-of-illness of HS was €6,791 per patient.
- result The main cost components were productivity loss (53.3%), biological treatment (21.5%), and informal care (9.2%).
- n among 200 adult HS patients
Expert Rev Pharmacoecon Outcomes Res · PMID 33629618 · Read it on PubMed ↗
Condamina et al. 2021
Baseline Characteristics of a National French E-Cohort of Hidradenitis Suppurativa in ComPaRe and Comparison with Other Large Hidradenitis Suppurativa Cohorts
Describes HS patient traits, no treatment tested.RegistryLow qualityRelated question
396 people2021
Most patients had moderate to severe disease, many were smokers or overweight, and antibiotics were the most common treatment while few received biologics; disease severity was linked to obesity and certain body sites including the gluteal fold and groin.
Who was studied
adults with hidradenitis suppurativa enrolled in a French patient e-cohort
What they received
treatment history (mainly oral antibiotics, less often biologics)
Compared with
no comparator group; descriptive cross-sectional data only
Main outcome
clinical characteristics and treatment history of hidradenitis suppurativa patients
Quality
This is a self-reported, cross-sectional survey with no control group, so it can describe patterns but not prove any treatment works.
Limitations
Cross-sectional, patient-reported data from a self-selected web cohort; no comparator group and no outcome testing of treatment effectiveness.
Taken word for word from the abstract
- n A total of 396 participants (339 females, 57 males) were included
- population HS participants in the Community of Patients for Research (ComPaRe) cohort
- intervention The most frequently prescribed treatments were oral antibiotics (n = 362, 91.4%), especially amoxicillin-clavulanic acid and cyclins. Less than 10% of participants received biologics.
- comparator We performed a cross-sectional study of the baseline data of HS participants in ComPaRe
- primaryOutcome The aim of this study was to describe the clinical characteristics and treatment history of HS participants in the Community of Patients for Research (ComPaRe) cohort
- result Most of the participants declared a Hurley stage II (n = 263, 66.4%) or III (n = 76, 20.3%).
- result Increased disease stage was associated with obesity (25.9 vs. 33.8 vs. 51.3%, p = 0.02) and some HS localizations (genital [p < 0.005], pubis [p < 0.007], gluteal fold [p = 0.02], and groin [p < 0.0001]).
Dermatology · PMID 33503635 · Read it on PubMed ↗
Luzzati et al. 2020
SAPHO syndrome: the supposed trigger by isotretinoin, the efficacy of adalimumab and the specter of depressive disorder: a case report
Biologic drug controlled rare syndrome.Case seriesVery low qualityRelated question
1 people2020
switching to adalimumab achieved good control of the disease
Who was studied
a boy with severe acne and depression who developed joint and bone inflammation after acne treatment
What they received
a biologic drug called adalimumab (blocks TNF-alpha)
Compared with
anti-inflammatory drugs (NSAIDs) used first
Main outcome
control of the inflammatory disease
Quality
This is a single patient case report, so it cannot show whether this applies to other people.
Limitations
Single case report; no control group; causal role of isotretinoin not established.
Taken word for word from the abstract
- n The case of a boy, affected by acne fulminans and depression
- population The case of a boy, affected by acne fulminans and depression, who presented with sacroiliitis after a 10-week treatment with isotretinoin is presented.
- intervention the switch to a TNF-α antagonist (Adalimumab)
- comparator After SAPHO diagnosis, NSAIDs therapy was started
- primaryOutcome with the achievement of a good control of the disease
- result required the switch to a TNF-α antagonist (Adalimumab) with the achievement of a good control of the disease
Ital J Pediatr · PMID 33187546 · Read it on PubMed ↗
González-Manso et al. 2021
Hidradenitis Suppurativa: Proposal of Classification in Two Endotypes with Two-Step Cluster Analysis
One HS subtype mainly affects buttocksRetrospectiveLow qualityRelated question
103 people2021
patients split into two subtypes: one with early onset, posterior (buttock/back) nodules, higher IL-10, gamma-secretase gene mutations and history of pilonidal sinus; the other with later onset, front-of-body lesions, obesity, and higher inflammatory markers
Who was studied
103 patients diagnosed with hidradenitis suppurativa (a chronic inflammatory skin disease)
What they received
statistical cluster analysis grouping patients by clinical features, genetics and blood markers
Main outcome
identifying distinct disease subtypes (endotypes) of hidradenitis suppurativa
Quality
this is a small, cross-sectional analysis of existing patients with no control group or outcome testing, so it mainly describes patterns rather than proving causes.
Limitations
small sample size, cross-sectional design with no follow-up, and no testing of why lesions occur—only grouping of existing patients by shared traits
Taken word for word from the abstract
- population We attempted at classifying 103 patients using two-step cluster analysis.
- intervention two-step cluster analysis
- primaryOutcome The resultant model defined two groupings or clusters
- result cluster 1 (64.9% of patients) characterized by nonobese males, with nodular lesions in posterior sites, early-onset HS, higher IL-10, presence of gamma-secretase mutations, and history of pilonidal sinus; and cluster 2 (35.1% of patients) characterized by obese females or males, with lesions in anterior sites, more presence of sinus tracts and abscesses and less nodules, later-onset HS, and higher concentrations of IL-1, CRP, IL-17, and IL-6
- n 103 patients using two-step cluster analysis
Dermatology · PMID 33171462 · Read it on PubMed ↗
Garg et al. 2021
Development and Validation of HSCAPS-1: A Clinical Decision Support Tool for Diagnosis of Hidradenitis Suppurativa over Cutaneous Abscess
Tool tells HS from abscess.RetrospectiveLow qualityRelated question
9,534 people2021
The simplified model showed good discrimination (c-statistic 0.746 [SE 0.013]) and moderate calibration (calibration intercept -0.260 [SE 0.055]; calibration slope 1.142 [SE 0.076])
Who was studied
patients with an ambulatory visit associated with either HS or cutaneous of the axilla, groin, perineum, and buttock
What they received
a clinical decision support to predict diagnosis of HS
Compared with
cutaneous abscess of the axilla, groin, perineum, and buttock
Main outcome
predicted probability of HS diagnosis
Quality
it is a retrospective records-based study without independent outside validation, so it mainly shows a diagnostic tool works reasonably well rather than proving why bumps form.
Taken word for word from the abstract
- population patients with an ambulatory visit associated with either HS or cutaneous of the axilla, groin, perineum, and buttock
- intervention a clinical decision support to predict diagnosis of HS
- comparator cutaneous abscess of the axilla, groin, perineum, and buttock
- primaryOutcome predicted probability of HS diagnosis
- result The simplified model showed good discrimination (c-statistic 0.746 [SE 0.013]) and moderate calibration (calibration intercept -0.260 [SE 0.055]; calibration slope 1.142 [SE 0.076])
- n Development set included 7,974 patients
- n Validation set included 1,560 patients
Dermatology · PMID 33099547 · Read it on PubMed ↗
Cazzaniga et al. 2021
Characterization of Hidradenitis Suppurativa Phenotypes: A Multidimensional Latent Class Analysis of the National Italian Registry IRHIS
One skin-disease subtype involves buttock bumps, mainly in men.RegistryLow qualityRelated question
965 people2021
three patient subtypes were found; one subtype, mostly non-obese men, had a high chance of lesions on the buttocks and groin along with acne and pilonidal cysts
Who was studied
patients with hidradenitis suppurativa (a chronic skin condition) seen at Italian dermatology clinics
What they received
none - this was an observational study classifying patients into disease subtypes, not testing a treatment
Compared with
none - subtypes were compared to each other, not to a treatment or placebo
Main outcome
identifying distinct subtypes (phenotypes) of hidradenitis suppurativa based on where lesions occur and other traits
Quality
this is a descriptive, cross-sectional analysis of registry patients without a comparison group or outcome testing, so it cannot establish cause of buttock pimples, only describe patterns within an already-diagnosed condition.
Limitations
cross-sectional design, patients already diagnosed with hidradenitis suppurativa rather than general population with buttock pimples, no testing of treatment or cause-effect
Taken word for word from the abstract
- n Overall, 965 patients aged 32.0 ± 12.4 years (mean ± SD) were evaluated.
- population a cohort of patients examined at 17 dermatological centers participating in the Italian Registry of Hidradenitis Suppurativa
- primaryOutcome To identify the HS phenotypes that best explain the disease heterogeneity, a cross-sectional study using latent class (LC) analysis was conducted
- result Patients in LC2 (29.6%) were nonobese males, with moderate disease severity; with a high probability of gluteal (0.50) and genital (0.17) lesions, besides axillary‒groin involvement; and with acne and pilonidal cysts.
- intervention a cross-sectional study using latent class (LC) analysis was conducted on a cohort of patients
- comparator A three-class model in LC analysis best fitted the data.
J Invest Dermatol · PMID 33098826 · Read it on PubMed ↗
Thorlacius et al. 2022
Sub-classification of Hidradenitis suppurativa: a cross-sectional study
Lower-type HS pattern often involves buttocks.RegistryLow qualityRelated question
524 people2022
Found two distinct patterns: an 'upper type' affecting armpits and breast area, and a 'lower type' affecting groin, genitals, anus and buttocks
Who was studied
people diagnosed with hidradenitis suppurativa (a skin condition causing recurrent boils/pimples in skin folds)
What they received
no treatment tested – patients were surveyed about where their flare-ups occur
Compared with
none (no comparison group, single group survey)
Main outcome
pattern of where HS flare-ups occur on the body
Quality
This was a one-time self-reported questionnaire with only 62% response rate and no comparison group, so it can describe patterns but not prove causes.
Limitations
Abstract notes it is a cross-sectional questionnaire-based design with 62% response rate and relies on self-reported flare locations rather than clinical examination or causal testing.
Taken word for word from the abstract
- n A total of 524 (62%) of 845 invited patients answered the questionnaire
- population All patients with a clinically confirmed diagnosis of HS registered at our department until March 1, 2017 were invited to participate.
- intervention using a cross-sectional questionnaire-based design
- comparator The frequency of HS flares in various anatomic locations was used for identification of possible HS subtypes using Principal Component Analysis (PCA) and cluster analysis.
- primaryOutcome The frequency of HS flares in various anatomic locations was used for identification of possible HS subtypes
- result we identified two possible subtypes of HS, labeled the "upper type" and the "lower type"
Arch Dermatol Res · PMID 33089403 · Read it on PubMed ↗
Ayala et al. 2020
Surgical management of advanced hidradenitis suppurativa via a one-stage procedure: A single-center experience
Skin grafting more successful than stitchingRetrospectiveLow qualityRelated question
139 people2020
skin grafting succeeded in 75% of cases versus 60% for primary closure; success was lowest in the gluteal and perineal areas (54% and 50%)
Who was studied
patients with advanced hidradenitis suppurativa needing surgery
What they received
single-stage surgery (skin removal with skin grafting or direct closure)
Compared with
primary closure versus skin grafting after excision
Main outcome
surgical success (healing without recurrence)
Quality
this is a retrospective single-center review without a control group, so it can't reliably prove one method is better.
Limitations
retrospective design, no comparison group, single center, and high complication/readmission rates reported
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a debilitating skin condition; in severe forms it requires excision and skin grafting for cure
- intervention 139 one-stage procedures were performed: 35 excision and primary closure, 104 split-thickness skin grafting (STSG)
- comparator Success rate was higher for STSG at 75% versus 60% with primary closure
- primaryOutcome Success rate was higher for STSG at 75% versus 60% with primary closure
- result Axilla procedures were most successful at 91% compared to 70%, 54%, and 50% for inguinal, gluteal, and perineal areas, respectively
- n 139 one-stage procedures were performed
Am J Surg · PMID 33051068 · Read it on PubMed ↗
Dumont et al. 2020
Increased risk of permanent stoma in Crohn's disease associated with hidradenitis suppurativa: a case-control study
Worse Crohn's outcomes, not simple pimplesCase-controlLow qualityRelated question
4,645 people2020
Crohn's disease patients with hidradenitis suppurativa had more active disease, needed more anti-TNF treatment, and had a much higher rate of ending up with a permanent stoma
Who was studied
people with Crohn's disease seen at a gastroenterology hospital
What they received
having hidradenitis suppurativa (a chronic skin disease) alongside Crohn's disease
Compared with
Crohn's disease patients without hidradenitis suppurativa
Main outcome
disease activity and need for a permanent stoma (bowel diversion surgery)
Quality
this is a retrospective case-control study from one hospital with a small number of cases, so it shows an association but cannot prove cause, and it doesn't address common pimples in general.
Limitations
retrospective design, single tertiary care center, small number of HS cases (44), matched controls which can introduce selection effects
Taken word for word from the abstract
- n included 4645 patients with CD referred to Saint-Antoine Hospital gastroenterology tertiary care centre between 2003 and 2016
- population 4645 patients with CD referred to Saint-Antoine Hospital gastroenterology tertiary care centre
- intervention Hidradenitis suppurativa prevalence was 0.95% (44 cases)
- comparator CD with HS was more active (56% vs 40% years with active disease, P < 0.001)
- primaryOutcome HS was associated with a higher risk of permanent stoma, 16.8% (IQR 7.5-33.3) vs 2.5% (IQR 0.8-7.4) in the control group (P = 0.002).
- result Multivariate analysis confirmed HS as independent risk factor for permanent stoma (odds ratio 6.19; 95% CI, 2.30-38.33; P < 0.001).
Aliment Pharmacol Ther · PMID 32525586 · Read it on PubMed ↗
Nomura 2020
Hidradenitis Suppurativa as a Potential Subtype of Autoinflammatory Keratinization Disease
Boils linked to immune and skin-growth problems, not simple pimples.Narrative reviewLow qualityRelated question
size not given2020
Suggests the condition arises from abnormal skin cell growth (keratinization) combined with self-driven inflammation, possibly forming a distinct inflammatory skin disease category
Who was studied
people with hidradenitis suppurativa (boils/cysts in skin areas like armpits, groin, buttocks)
What they received
understanding the biological causes of hidradenitis suppurativa
Main outcome
proposed mechanism explaining why hidradenitis suppurativa develops
Quality
This is an opinion-style review summarizing other studies' findings rather than new patient data, so it cannot prove cause or treatment effect.
Limitations
No new patient data or experiments; synthesizes genetic, mouse, and treatment-response findings from other studies to propose a disease concept.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition, clinically characterized by boiled cysts, comedones, abscesses, hypertrophic scars, and/or sinus tracts typically in the apocrine-gland-rich areas such as the axillae, groin, and/or buttocks.
- result These findings collectively suggest that HS is closely linked with aberrant keratinization and autoinflammation, raising the question whether it represents an autoinflammatory keratinization disease, a recently proposed disease entity.
- primaryOutcome In this mini review, I introduce the concept of autoinflammatory keratinization disease and attempt to address this clinically important question.
- intervention I herein emphasize the importance of the following three recent discoveries in the pathogenesis of HS
Front Immunol · PMID 32508815 · Read it on PubMed ↗
Garbayo-Salmons et al. 2020
Hidradenitis Suppurative: Our Experience with a Surgical Case Management Team
Surgery mostly helped, but relapse occurred.Case seriesLow qualityRelated question
104 people2020
63.4% had satisfactory postoperative outcomes, 20% had lesion recurrence, and 12% had wound dehiscence
Who was studied
Patients with hidradenitis suppurativa evaluated by a surgical case management team
What they received
Surgical treatment (mainly deroofing) often combined with rifampicin and clindamycin
Main outcome
Postoperative outcome (satisfactory result, recurrence, wound complications)
Quality
This is a descriptive study of one surgical team's patients without a comparison group, so it can't show whether treatment caused the improvement.
Limitations
Descriptive cross-sectional study, single center, no control group, outcomes assessed subjectively as 'satisfactory'.
Taken word for word from the abstract
- population Descriptive cross-sectional study of 104 patients evaluated by our surgical case management team between September 2015 and July 2018.
- n Descriptive cross-sectional study of 104 patients
- intervention Deroofing was the technique used most often (in 48% of the patients who underwent surgery).
- intervention The most common drug treatment was a combination of rifampicin and clindamycin
- primaryOutcome Postoperative outcomes were assessed as satisfactory overall in 63.4% of the cases.
- result The HS lesion recurred in 20% and 12% developed wound dehiscence.
Actas Dermosifiliogr (Engl Ed) · PMID 32408974 · Read it on PubMed ↗
Giuffrida et al. 2021
Novel Therapeutic Approaches and Targets for the Treatment of Hidradenitis Suppurativa
New drugs help a different buttock skin disease, not acne.Narrative reviewLow qualityRelated question
size not given2021
newer targeted drugs and laser treatment showed clinically meaningful efficacy with good short-term safety
Who was studied
people with hidradenitis suppurativa, a chronic inflammatory skin condition often affecting buttocks and other skin folds
What they received
newer targeted therapies such as drugs blocking TNF-alpha, IL-1β, IL-23/Th17 pathways, PDE4 inhibitors, and laser treatment
Compared with
traditional treatments including anti-inflammatories, antibiotics and surgery
Main outcome
treatment efficacy and safety for hidradenitis suppurativa
Quality
this is a narrative literature review summarizing other studies, not original controlled data, so it can't prove these treatments work.
Limitations
no systematic review methodology described, no quantitative data, and it addresses hidradenitis suppurativa rather than common acne-type pimples
Taken word for word from the abstract
- population Hidradenitis Suppurativa (HS) is a chronic, recurrent and disabling inflammatory skin condition, clinically characterized by nodules, bullae, abscesses, fistulae, and draining sinus tracts mainly located in axillae, inguinal folds, inframammary region and buttocks
- intervention studies on tumor necrosis factor-α, IL-1β, IL-10, and the IL-23/T-helper (Th) 17 and IL12/Th1 axes in immune dysregulation in HS have helped in developing new regimens. Inhibitor of phosphodiesterase 4 and laser treatments
- comparator many patients do not respond to the traditionally available systemic treatments, including antiinflammatories, antibiotics and surgery
- primaryOutcome We review the current knowledge on newer therapeutic approaches and targets for the treatment of HS
- result Inhibitor of phosphodiesterase 4 and laser treatments have shown clinically meaningful efficacy with good short-term safety and tolerability.
Curr Pharm Biotechnol · PMID 32368973 · Read it on PubMed ↗
Riverain-Gillet et al. 2020
The Surface Microbiome of Clinically Unaffected Skinfolds in Hidradenitis Suppurativa: A Cross-Sectional Culture-Based and 16S rRNA Gene Amplicon Sequencing Study in 60 Patients
Altered skin bacteria near buttocks.Case-controlLow qualityRelated question
77 people2020
Even unaffected buttock crease and groin/armpit skin in hidradenitis suppurativa patients had more anaerobic bacteria like Prevotella and less of the normal skin bacteria Staphylococcus epidermidis, with the buttock crease being the most affected site
Who was studied
people with hidradenitis suppurativa and healthy people, sampled on non-affected armpits, groin folds, and buttock creases
What they received
skin swabs from clinically normal-looking skinfolds in hidradenitis suppurativa patients
Compared with
skin swabs from the same skinfold areas in healthy people without hidradenitis suppurativa
Main outcome
types and amounts of bacteria living on the skin (microbiome)
Quality
It is a small observational study comparing two groups that also differed a lot in smoking rates, so it cannot prove what causes the bacterial differences.
Limitations
Patients and controls differed strongly in smoking (87% vs 6%), which could affect skin bacteria independent of disease; study is cross-sectional so cause and effect cannot be determined.
Taken word for word from the abstract
- population We studied the microbiome of clinically unaffected typical HS sites (armpits, inguinal folds, and gluteal clefts) in 60 patients with HS and 17 healthy controls.
- n 60 patients with HS and 17 healthy controls
- intervention A total of 192 samples obtained by swabbing were analyzed by bacterial cultures.
- comparator 60 patients with HS and 17 healthy controls
- primaryOutcome We studied the microbiome of clinically unaffected typical HS sites
- result HS skinfolds were characterized by an increased abundance of anaerobes, predominantly Prevotella, but also Actinomyces, Campylobacter ureolyticus, and Mobiluncus, contrasting with a lower abundance of skin commensals such as Staphylococcus epidermidis, a major component of the skin microbiome; Kocuria; and Micrococcus luteus.
- result the gluteal cleft being the most anaerobic area, followed by inguinal folds and axilla (P = 3 × 10-6)
- limitations Patients and controls showed similar characteristics, except for smoking (87% vs. 6%, respectively).
J Invest Dermatol · PMID 32339539 · Read it on PubMed ↗
Kim et al. 2020
Reconstruction of bilateral inferomedial gluteal defects after resection of hidradenitis suppurativa with symmetrical keystone flaps designed parallel to relaxed skin-tension lines: A case report
Successful surgical repair after cyst removal.Case seriesVery low qualityRelated question
1 people6 months
both flaps fully survived with no complications and patient was satisfied at 6 months
Who was studied
18-year-old man with chronic inflammatory lesions on both buttocks (hidradenitis suppurativa)
What they received
surgical removal of affected skin followed by reconstruction with symmetrical keystone flaps
Compared with
none
Main outcome
flap survival and healing without complications after surgery
Quality
This is a single patient case report, so it cannot show whether this approach works in general.
Limitations
Only one patient was studied, so findings may not generalize; this addresses surgical treatment of an existing severe condition rather than why pimples occur on the buttocks.
Taken word for word from the abstract
- population An 18-year-old man was admitted for chronic inflammatory lesions in both inferomedial gluteal areas.
- intervention We performed wide excision on all affected lesions.
- intervention We covered the defects with KFs 9 × 15 cm (right) and 8 × 12 cm (left)
- comparator RATIONALE: Surgical treatment of hidradenitis suppurativa (HS) is challenging.
- primaryOutcome The flaps were inset without tension on each side, and the donor sites were closed primarily.
- result All flaps fully survived and there were no postoperative complications. The patient was satisfied with the final outcome after 6 months of follow-up.
- n An 18-year-old man was admitted
Medicine (Baltimore) · PMID 32243413 · Read it on PubMed ↗
Shavit et al. 2020
The surgeon’s perspective: a retrospective study of wide local excisions taken to healthy subcutaneous fat in the management of advanced hidradenitis suppurativa
Similar recurrence with either wound closure method.RetrospectiveLow qualityRelated question
66 people14.5 (range 1–55) months
recurrence was the same in both closure methods, about 18% in each
Who was studied
patients with advanced hidradenitis suppurativa needing surgery, including buttock involvement
What they received
wide local excision down to healthy fat, closed with skin flaps
Compared with
wide local excision closed by secondary intention (left open to heal)
Main outcome
local recurrence of disease after surgery
Quality
this is a single-center retrospective chart review without randomization, so it can't reliably prove one method is better.
Limitations
retrospective design, no control group without surgery, variable follow-up time, outcomes extracted from charts
Taken word for word from the abstract
- population patients with HS who were under concurrent surgical and dermatologic care
- intervention One hundred procedures were closed primarily with rotation or advancement flaps
- comparator 33 by secondary intention healing
- primaryOutcome Local recurrence occurred in 18% of primary closures and 18% of secondary intention closures
- result p = 0.98, χ2 test, no difference between groups
- n A total of 66 patients underwent 133 WLE to healthy subcutaneous fat.
- followUp Median follow-up was 14.5 (range 1–55) months.
Can J Surg · PMID 32109015 · Read it on PubMed ↗
Hessam et al. 2020
[Hidradenitis suppurativa/acne inversa in the genitoanal region]
Describes a skin disease, not simple pimples.Narrative reviewVery low qualityRelated question
size not given2020
Genital/anal area involvement, especially around the buttocks and perineum, was more common in men, while armpit/groin/under-breast involvement was more common in women; this location was linked to worse quality of life and sexual health, and serious complications like fistulas, lymphedema, and skin cancer can occur
Who was studied
People with hidradenitis suppurativa (acne inversa), a chronic inflammatory skin disease, that affects the genital and anal area
What they received
Not a treatment study; this review describes disease patterns and complications rather than testing a treatment
Compared with
No comparator treatment is described; the review compares body site locations (genitoanal vs other areas) rather than treatments
Main outcome
How often the genital/anal area is affected, and what complications occur there, including effect on quality of life
Quality
This is a general descriptive review summarizing prior findings, not a study testing a treatment or directly measuring outcomes itself.
Limitations
The abstract does not describe its research methods, does not report how many patients were studied, and does not test any treatment — it only summarizes known patterns and complications of a specific skin disease (hidradenitis suppurativa), which is one possible but not confirmed cause of buttock pimples.
Taken word for word from the abstract
- population Hidradenitis suppurativa/acne inversa (HS/AI) is a chronic inflammatory skin disease.
- intervention The knowledge of perianal fistula formation, pubogenital lymphedema and squamous cell carcinoma, which are three of the most severe complications, is critical for adequate treatment.
- comparator Axillary, submammary and inguinal localizations seem to be more prevalent in women.
- primaryOutcome Involvement of the genitoanal region is associated with a higher reduced quality of live and sexual health compared to other locations.
- result Several studies showed that perianal, perineal and gluteal involvement is more common in men.
Hautarzt · PMID 32077977 · Read it on PubMed ↗
Peterson et al. 2020
Analysis of Characteristics and Trends in Treatment Response of Hidradenitis Suppurativa Patients: A Southern US Cohort Study
Buttock lesions responded better to treatment.RetrospectiveLow qualityRelated question
149 people2020
Disease on the buttocks had a significantly higher treatment response rate than disease elsewhere, and biologic therapy showed a near-significant trend toward better response than other treatments
Who was studied
patients with hidradenitis suppurativa seen at a dermatology clinic in the southern United States
What they received
various treatments including oral antibiotics, topical antibiotics, metabolic medications like metformin/zinc, steroid injections, and biologic TNF-α inhibitors
Compared with
other treatments compared to biologics, and disease located on the buttocks compared to other body sites
Main outcome
how well patients responded to treatment
Quality
This was a single-center retrospective chart review without randomization, so its treatment comparisons are only preliminary.
Limitations
Retrospective chart review from a single academic center; the biologic response finding did not reach statistical significance (p = 0.0632).
Taken word for word from the abstract
- design A retrospective chart review was conducted of a cohort of HS patients
- n A total of 149 patients (113 females, 36 males) were included.
- population patients with HS in a single academic referral center in the southern USA
- intervention The most frequently prescribed treatments were oral antibiotic therapy (83.9%), topical antibiotic therapy (74.5%), metabolic medications such as metformin/zinc (67.1%), intralesional Kenalog (63.1%), and biologic therapies (tumor necrosis factor-α inhibitors; TNF-α inhibitors; 49%).
- comparator patients with disease localized to the buttocks had significantly higher response rates (60.4 vs. 25%, p = 0.043) and approached statistical significance in responders versus nonresponders in treatment with biologics (p = 0.0632) when compared against all other treatments
- primaryOutcome to broadly examine trends in treatment response of various therapeutic strategies in patients with HS
- result patients with disease localized to the buttocks had significantly higher response rates (60.4 vs. 25%, p = 0.043) and approached statistical significance in responders versus nonresponders in treatment with biologics (p = 0.0632) when compared against all other treatments
Dermatology · PMID 31935718 · Read it on PubMed ↗
Li et al. 2019
[Clinical therapeutic observation on sequential treatment of chronic wounds with repeated recurrence of hidradenitis suppurativa in buttocks]
Surgery healed severe buttock boils.Case seriesLow qualityRelated question
15 people1 to 5 years
all skin grafts/flaps survived, wounds healed, and no hidradenitis suppurativa recurred at the surgery site during 1 to 5 years of follow-up, though one patient had a separate complication from an anal fistula
Who was studied
men with severe recurrent hidradenitis suppurativa (boil-like lumps) on the buttocks after multiple prior surgeries
What they received
wide surgical removal of lesions, followed by vacuum wound suction with oxygen-fluid rinsing, then skin grafts or flaps
Compared with
each patient's own condition before treatment (no separate comparison group)
Main outcome
wound healing, infection clearance, and recurrence of hidradenitis suppurativa after treatment
Quality
this was a small uncontrolled study of only 15 patients comparing them to themselves before and after treatment, so it cannot rule out other explanations for improvement.
Limitations
small sample size, no control group, all male patients with a different and more severe condition (hidradenitis suppurativa) than typical acne pimples
Taken word for word from the abstract
- population 15 male patients (aged 26-53 years) hospitalized in our burn ward with Hurley's stage Ⅲ HS in the buttocks recurred after 2-5 operations
- intervention extensive resection of the lesion, continuous VSD combined with intermittent irrigation of oxygen-loaded fluid
- intervention autologous posterior thigh split-thickness skin grafts and/or local flaps were transplanted to repair the wounds
- comparator prospective self pre- and post-control study
- primaryOutcome Survival of skin grafts and flaps after operation was observed, hospitalization time was recorded, and recurrence and complications of HS were followed up.
- result The skin grafts and/or flaps of 15 patients survived post operation, and the wounds were healed.
- result During follow-up of 1 to 5 years, no recurrence of HS occurred in operative site of buttocks of 15 patients, but 1 patient had ulceration of healed perianal incision caused by high anal fistula and was healed after treatment.
- n 15 male patients (aged 26-53 years)
- followUp follow-up of 1 to 5 years
Zhonghua Shao Shang Za Zhi · PMID 31658548 · Read it on PubMed ↗
Takeda et al. 2019
Ustekinumab treatment for hidradenitis suppurativa
Most improved on ustekinumab.Case seriesLow qualityRelated question
24 people3-5 months
most patients began to improve after 3-5 months and some reached complete remission
Who was studied
people with hidradenitis suppurativa, a skin disease affecting armpits, groin, buttocks and vulval area
What they received
ustekinumab injections
Compared with
no control group; included patients previously treated with anti-TNF drugs
Main outcome
improvement or remission of hidradenitis suppurativa symptoms
Quality
This is a small case report plus review of only 24 patients with no control group, so it cannot reliably prove the treatment works.
Limitations
Based on a single case report combined with a literature review of other reported cases, not a controlled study.
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a follicular occlusive inflammatory skin disease that occurs in the axilla, groin, buttocks and vulval region.
- intervention ustekinumab treatments for HS
- comparator Ten (10/24, 41.6%) had received anti-TNF drugs including infliximab, adalimumab and etanercept prior to UST treatment for HS.
- primaryOutcome Control of the intractable inflammation is a primary goal of HS treatments.
- result HS in most of the cases started to improve after 3-5 months of UST initiation, and some achieved complete remission.
- n Twenty-four HS patients, 16 women and eight men, have been treated with ustekinumab.
J Dermatol · PMID 31638283 · Read it on PubMed ↗
Kawak 2019
Hidradenitis Suppurativa
Case report, no outcome given.Case seriesVery low qualityRelated question
1 people2019
Who was studied
an obese diabetic man with a 20-year history of perianal, inguinal, and gluteal hidradenitis suppurativa
What they received
surgical removal of sinus tracts and diseased skin (unroofing and excision)
Compared with
previous treatments with doxycycline and infliximab
Quality
This is a single patient case report, so it cannot show whether the treatment generally works.
Limitations
Only one patient described; no follow-up results or outcome data given in the abstract.
Taken word for word from the abstract
- population A 66-year-old obese (BMI 34) diabetic man, a former smoker who had quit 4 months ago, had a 20-year history of perianal, inguinal, and gluteal hidradenitis suppurativa.
- intervention The patient underwent extensive unroofing of the sinus tracts and excision of active disease
- comparator previously on doxycycline and infliximab with little improvement in his symptoms
- n A 66-year-old obese (BMI 34) diabetic man
Dis Colon Rectum · PMID 31596759 · Read it on PubMed ↗
Kurihara et al. 2019
Gluteal hidradenitis suppurativa presenting pemphigus-like findings: case report
Rare case, unusual immune findings.Case seriesVery low qualityRelated question
1 people2019
the patient had gluteal hidradenitis suppurativa together with pemphigus-like findings, suggesting a possible link between the two conditions
Who was studied
68-year-old man with hidradenitis suppurativa on the buttocks
What they received
none (case report describing disease features)
Main outcome
presence of pemphigus-like skin findings (acantholysis and desmoglein autoantibodies) alongside hidradenitis suppurativa
Quality
this is a single patient case report, so it cannot show what causes butt pimples in general or how common this is.
Limitations
only one patient; no comparison group; findings may not generalize to typical cases of buttock acne or folliculitis
Taken word for word from the abstract
- population We report a case of 68-year-old male with a diagnosis of gluteal hidradenitis suppurativa co-presenting pemphigus-like findings including acantholysis and positive desmoglein autoantibodies.
- intervention We report a case of 68-year-old male with a diagnosis of gluteal hidradenitis suppurativa co-presenting pemphigus-like findings including acantholysis and positive desmoglein autoantibodies.
- primaryOutcome co-presenting pemphigus-like findings including acantholysis and positive desmoglein autoantibodies
- result comorbidity of gluteal hidradenitis suppurativa and pemphigus-like findings has not been reported before
- n a case of 68-year-old male
BMC Dermatol · PMID 31337387 · Read it on PubMed ↗
Benhadou et al. 2019
Pilonidal sinus disease: an intergluteal localization of hidradenitis suppurativa/acne inversa: a cross-sectional study among 2465 patients
Butt bumps often linked to pilonidal disease.RetrospectiveLow qualityRelated question
2,465 people2019
Of patients with available diagnosis, pilonidal sinus disease was found in 78% and intergluteal hidradenitis suppurativa in 22% of those with intergluteal lesions
Who was studied
people diagnosed with hidradenitis suppurativa, a chronic skin condition causing inflamed lumps and abscesses
What they received
having lesions in the fold between the buttocks (intergluteal fold)
Compared with
patients without intergluteal fold lesions
Main outcome
how common pilonidal sinus disease and intergluteal hidradenitis suppurativa were among patients with lesions in that area
Quality
This was a retrospective study without consistent clinical confirmation of diagnoses, so misclassification was possible and it doesn't test a treatment or directly explain acne-like pimples.
Limitations
Possible misclassification bias since clinical/image-based diagnosis or histopathology of intergluteal lesions was not always available
Taken word for word from the abstract
- n From a total of 2465 patients with HS included in the study
- population Hidradenitis suppurativa (HS), also referred to as acne inversa, is a debilitating skin disease characterized by inflammatory nodules, chronic abscesses and tunnels (fistulae and sinuses)
- intervention 661 (27%) reported lesions in the IGF
- comparator These patients were significantly more often smokers and had more severe HS
- primaryOutcome To determine the prevalence and characteristics of inflammatory skin lesions located in the intergluteal fold (IGF) of patients with HS
- result Of the 238 patients with an available clinical diagnosis, intergluteal-HS (IG-HS) was diagnosed in 52 patients (22%) and PSD was diagnosed in 186 patients (78%)
- limitations There was a possibility of misclassification bias in this study as a clinical/image-based diagnosis or histopathology of the IGF lesions was not always available
Br J Dermatol · PMID 30919434 · Read it on PubMed ↗
Zimman et al. 2019
Hidradenitis Suppurativa: Estimated Prevalence, Clinical Features, Concomitant Conditions, and Diagnostic Delay in a University Teaching Hospital in Buenos Aires, Argentina
Chronic skin condition behind some buttock bumps.RetrospectiveLow qualityRelated question
66 people2019
the condition mainly affected armpits, vulva and groin, was linked to smoking, overweight and obesity, and male sex plus buttock/perianal location were linked to more severe disease, with diagnosis often delayed for years
Who was studied
patients diagnosed with hidradenitis suppurativa treated at a hospital in Buenos Aires
What they received
none; this was an observational study describing disease features rather than testing a treatment
Compared with
none
Main outcome
prevalence, clinical features, concomitant conditions, and diagnostic delay in hidradenitis suppurativa
Quality
This is a small, single-center chart review with no comparison group, so it can describe patterns but not prove what causes the bumps.
Limitations
Retrospective, single hospital, small confirmed sample (66 of 180 initial cases), and findings may not generalize beyond this population.
Taken word for word from the abstract
- n the diagnosis was confirmed in 66 cases
- population all patients with a diagnosis of hidradenitis suppurativa managed in Hospital Italiano de Buenos Aires
- intervention Retrospective descriptive cross-sectional study.
- comparator Retrospective descriptive cross-sectional study.
- primaryOutcome To describe the prevalence and clinical features of hidradenitis suppurativa in patients treated at Hospital Italiano de Buenos Aires and determine the frequency of comorbidities and time to diagnosis in this population.
- result The armpits, vulva, and groin were the locations most frequently affected. Smoking, overweight, and obesity were the most commonly recorded concomitant conditions. Male sex and perianal and gluteal locations were associated with severity.
Actas Dermosifiliogr (Engl Ed) · PMID 30885385 · Read it on PubMed ↗
Cao et al. 2019
Nicastrin haploinsufficiency alters expression of type I interferon-stimulated genes: the relationship to familial hidradenitis suppurativa
Gene clue to rare inherited skin condition.Laboratory studyVery low qualityRelated question
size not given2019
NCSTN-reduced skin cells showed increased activity of inflammation-related genes and altered growth
Who was studied
human keratinocyte and embryonic kidney cell lines with reduced NCSTN gene activity
What they received
knocking down or deleting the NCSTN gene (linked to familial hidradenitis suppurativa) in cell lines
Compared with
control cells with normal NCSTN expression
Main outcome
changes in gene expression and inflammatory signaling pathways in skin cells
Quality
This is a basic lab experiment on cell lines, not on patients, so it cannot show whether any treatment helps or what causes pimples in general.
Limitations
Study was done only in cell lines, not in patients or tissue samples, and focused on a rare genetic form of hidradenitis suppurativa rather than common buttock pimples.
Taken word for word from the abstract
- population NCSTN was knocked down using a small hairpin RNA construct in both a keratinocyte cell line (HEK001) and an embryonic kidney cell line (HEK293)
- intervention a heterozygous deletion of NCSTN was created with CRISPR/Cas9 genome editing
- comparator Compared with controls, the keratinocyte NCSTN knockdown cell line showed a significantly increased expression of genes
- primaryOutcome differential gene expression was assessed using RNA microarray
- result the keratinocyte NCSTN knockdown cell line showed a significantly increased expression of genes related to the type I interferon response pathway
- result Both HEK001 and HEK293 knockdowns demonstrated evidence of altered growth.
Clin Exp Dermatol · PMID 30656721 · Read it on PubMed ↗
Bianchi et al. 2019
Sex-related differences of clinical features in hidradenitis suppurativa: analysis of an Italian-based cohort
HS bumps more common on men's buttocks.RetrospectiveLow qualityRelated question
124 people2019
Men more often had lesions in the buttock area, while women more often had them on the breast; overall severity was similar between sexes
Who was studied
Adults diagnosed with hidradenitis suppurativa (a chronic skin condition causing painful lumps) from six Italian dermatology clinics
What they received
Being male
Compared with
Being female
Main outcome
Where lesions appeared on the body and how severe the disease was
Quality
This is an observational study of a specific skin disease (not general acne) looking at sex differences, so it can't tell us why ordinary pimples occur on the buttocks.
Limitations
Observational design, no control group without the disease, and findings specific to hidradenitis suppurativa rather than common acne.
Taken word for word from the abstract
- population 124 patients with HS from 6 Italian dermatology centres participated in this study
- intervention more frequent in the gluteal region in men
- comparator more frequent on the breast in women
- primaryOutcome Disease severity was assessed using the Hidradenitis Suppurativa Physician's Global Assessment score (HS-PGA) and Hurley score
- result Lesions were more frequent in the gluteal region in men (32.3% in men vs. 8.7% in women, P < 0.001) and more frequent on the breast in women (16.3% in women vs. 4.6% in men, P = 0.02).
- n 124 patients with HS
Clin Exp Dermatol · PMID 30593710 · Read it on PubMed ↗
Agut-Busquet et al. 2019
Hidradenitis suppurativa of the nape: Description of an atypical phenotype related to severe early-onset disease in men
Severe HS linked to buttock lesions too.Case-controlLow qualityRelated question
377 people2019
Patients with nape involvement had worse disease, earlier onset, family history, and more often had buttock (gluteal) involvement
Who was studied
patients with hidradenitis suppurativa (HS)
What they received
having severe inflammatory lesions on the back of the neck (nape involvement)
Compared with
HS patients without nape involvement
Main outcome
disease severity and clinical features linked to nape involvement
Quality
This is a single-center, cross-sectional study with only 30 patients in the group of interest, so it can show associations but not prove causes.
Limitations
Single-center study, small subgroup (30 patients) with nape involvement, cross-sectional design so cause-and-effect can't be confirmed.
Taken word for word from the abstract
- n a total of 377 patients
- population Some patients with hidradenitis suppurativa (HS) develop severe inflammatory lesions of the nape.
- intervention patients with and without nape involvement
- comparator patients with and without nape involvement
- primaryOutcome to compare patients with and without nape involvement, to determine whether disease severity is greater in these patients and to describe their clinical characteristics
- result Patients with versus without nape involvement had greater disease severity, earlier disease onset, a family history of HS, lower body mass, and higher Dermatological Life Quality Index and pain scores. Amongst them, involvement of the trunk and gluteal regions predominated.
J Dermatol · PMID 30561771 · Read it on PubMed ↗
Veraldi et al. 2018
Multidisciplinary approach for hidradenitis suppurativa patients
Discusses hidradenitis suppurativa, no outcome data.Narrative reviewVery low qualityRelated question
size not given2018
the abstract describes the disease and argues for team-based care but does not report outcome data comparing approaches
Who was studied
people with hidradenitis suppurativa (a chronic skin condition affecting armpits, groin, buttocks and other skin fold areas)
What they received
multidisciplinary care involving multiple specialists
Compared with
dermatologist care alone
Main outcome
management of the disease and its associated health conditions
Quality
this is a descriptive discussion piece with no patient data or comparison of outcomes.
Limitations
no study data, numbers, or outcomes are reported; it is an opinion/overview article
Taken word for word from the abstract
- population Hidradenitis suppurativa or acne inversa is an inflammatory, chronic disease of the hair follicles located in specific areas of the skin surface (axillae, submammary, inguinal and intergluteal folds, pubis, genitalia and buttocks).
- intervention the cooperation with rheumatologists, gastroenterologists, endocrinologists, microbiologists/infectivologists, psychologists/psychiatrics and plastic surgeons is often helpful or necessary
- comparator The diagnosis and the management of this disease are usually made by the dermatologist.
- primaryOutcome the frequent association of hidradenitis suppurativa or acne inversa with important systemic comorbidities needs the cooperation with a number of specialists
- result the cooperation with rheumatologists, gastroenterologists, endocrinologists, microbiologists/infectivologists, psychologists/psychiatrics and plastic surgeons is often helpful or necessary
G Ital Dermatol Venereol · PMID 30468376 · Read it on PubMed ↗
Zouboulis et al. 2019
Standardized Photographic Documentation of Hidradenitis Suppurativa/Acne Inversa
Not relevant - photography method only.Laboratory studyVery low qualityRelated question
size not given2019
a standardized photography protocol was developed, no treatment or cause was tested
Who was studied
people with hidradenitis suppurativa (a skin fold condition), studied via volunteer photography
What they received
standardized photography method/protocol for documenting skin lesions
Main outcome
creating a reproducible photography protocol for documenting lesions in skin folds including buttocks
Quality
this is not a study of symptoms or causes at all, but a technical photography methods paper, so it cannot answer why someone gets pimples on their buttocks.
Limitations
abstract does not address causes, treatment or outcomes of buttock lesions, only documents a photography method
Taken word for word from the abstract
- population Pictures of volunteers were taken, and indicative scientific graphics were designed.
- intervention a standardized, reproducible photographic documentation of HS candidate skin areas (50 cm from the skin surface) is proposed
- primaryOutcome The aim of this work was to develop a standardized, representative and reproducible documentation of the multilocular hidradenitis suppurativa/acne inversa (HS) lesions
- result Standardized photography of candidate skin areas for HS involvement will allow longitudinal intraindividual and interindividual evaluation of the disease course as well as prospective and retrospective comparative studies.
Dermatology · PMID 30368496 · Read it on PubMed ↗
Chiricozzi et al. 2020
Characterization of comorbid conditions burdening hidradenitis suppurativa: a multicentric observational study
HS linked to obesity, PCOS, diabetes.RetrospectiveLow qualityRelated question
234 people2020
obesity, polycystic ovary syndrome, high blood pressure, high cholesterol, type 2 diabetes and thyroid problems were the most common conditions found, and obesity was linked to more severe disease and to PCOS
Who was studied
patients with hidradenitis suppurativa seen at specialist skin clinics
What they received
none (study just looked at related health conditions, not a treatment)
Main outcome
which other health conditions occur alongside hidradenitis suppurativa and whether they relate to disease severity
Quality
this was a chart-review study of one patient group with no comparison group, so it can show links but not prove what causes what.
Limitations
observational chart review, no control group, and it studies hidradenitis suppurativa rather than ordinary pimples
Taken word for word from the abstract
- population patients visited at the HS outpatient clinic of three University Dermatologic Departments
- n Two hundred thirty-four patients, mostly females (62%), were enrolled in this study.
- primaryOutcome This study aimed to described comorbid conditions affecting HS patients and to detect any correlation with disease severity.
- result The most frequently observed comorbidities were: obesity (26.1%), polycystic ovary syndrome (PCOS) (13.8% of the overall study population and 22.3% of females), hypertension (11.9%), dyslipidemia (9.9%), type II diabetes (9.5%), thyroid disorders (9.1%)
- result Obesity represented a key-comorbid condition increasing the likelihood of having more severe HS and PCOS (odds ratio 3.35 and 3.74, respectively).
- intervention Analyzing clinic database, we included all charts of patients visited at the HS outpatient clinic
G Ital Dermatol Venereol · PMID 30295448 · Read it on PubMed ↗
Yang et al. 2018
Demographic and clinical features of hidradenitis suppurativa in Korea
Buttocks commonly affected by hidradenitis suppurativa.RetrospectiveLow qualityRelated question
438 people2018
buttocks were the most commonly affected area after axillae and groin, and buttock or perineum involvement was linked to more severe disease
Who was studied
people diagnosed with hidradenitis suppurativa in Korea
What they received
none (this is an observational chart review, not a treatment study)
Compared with
comparison between patient subgroups (e.g. male vs female, different body sites) rather than a treatment comparator
Main outcome
which body areas were affected and what features were linked to more severe disease
Quality
this is a single retrospective chart review without a control group, so it describes patterns but cannot prove cause or test a treatment.
Limitations
Retrospective design based on medical records; only includes patients already diagnosed with hidradenitis suppurativa, so it may not reflect all causes of buttock pimples in the general population.
Taken word for word from the abstract
- n A total of 438 patients, diagnosed with HS from May 2007 to April 2017, were enrolled
- population we sought to investigate the demographic and clinical features of HS in Korea
- primaryOutcome The most frequently affected area was the buttocks, followed by axillae and groin
- result involvement of the perineum (OR, 4.067) and buttocks (OR, 1.471) tended to be associated with increased severity of the disease
- intervention the electronic medical record of each patient was reviewed
- comparator Male patients had severe diseases compared with females with an odds ratio (OR) of 1.790
J Dermatol · PMID 30294846 · Read it on PubMed ↗
Micieli et al. 2018
Lymphedema in patients with hidradenitis suppurativa: a systematic review of published literature
Rare HS swelling, not typical butt pimplesSystematic reviewVery low qualityRelated question
27 people2018
Most patients treated with surgical excision plus medical therapy had good outcomes; swelling most often affected the scrotum, penis or vulva, with buttocks affected in only 2 of 27 patients
Who was studied
People with long-standing hidradenitis suppurativa (a chronic boil-like skin condition) who developed lymphedema
What they received
Treatment of HS-related lymphedema, most often radical surgical removal of affected tissue plus medical therapy
Compared with
No comparison group; the review just pooled case reports and case series without controls
Main outcome
How lymphedema from HS presents and is managed
Quality
It only pools small case reports and case series with no control group, so it can't reliably show whether treatments work.
Limitations
Based on only 17 published reports (27 patients total) with no control group, and the abstract notes this complication is rare.
Taken word for word from the abstract
- n representing 27 patients
- population Lymphedema is a debilitating complication of hidradenitis suppurativa (HS) that can be therapeutically challenging.
- intervention The majority of cases (14 patients, 52%) were treated with radical surgical excision combined with medical therapy and obtained favorable outcomes.
- comparator Two case series and 15 case reports met inclusion criteria, representing 27 patients.
- primaryOutcome Systematic evaluation of the clinical presentation and management of this condition has yet to be performed.
- result The majority of cases (14 patients, 52%) were treated with radical surgical excision combined with medical therapy and obtained favorable outcomes.
- result buttocks (2 patients, 7%)
Int J Dermatol · PMID 30105858 · Read it on PubMed ↗
Maghsoudi et al. 2018
Men, main victims of hidradenitis suppurativa (A prospective cohort study)
Surgery beat conservative care for severe HS.Prospective cohortLow qualityRelated question
21 peopleat least 24 months
conservative treatment had little or no effect, while wide surgical excision was the only successful treatment
Who was studied
patients with moderate to extensive hidradenitis suppurativa, a chronic skin condition with painful lumps and abscesses
What they received
wide surgical excision with reconstruction of affected skin areas
Compared with
conservative (non-surgical) treatment methods
Main outcome
how well treatment worked, including recurrence of the disease after treatment
Quality
This was a small surgical case series of only 21 patients without a formal comparison group, so the findings are not strong evidence.
Limitations
Small number of patients, single hospital, and no randomized comparison group; abstract does not report complication or recurrence rates in detail.
Taken word for word from the abstract
- n 44 sites in 21 patients
- population moderate to extensive HS treated surgically
- intervention wide surgical excision and methods of reconstruction
- comparator Conservative treatment methods have little or no effects
- primaryOutcome the rate of recurrence
- result Conservative treatment methods have little or no effects especially on gluteal, perineal/perianal and axillary hidradenitis suppurativa. The morbidity associated with the established disease is significant, and the only successful treatment is wide surgical excision.
- followUp follow up of at least 24 months
Int J Surg · PMID 29284150 · Read it on PubMed ↗
Asamoah et al. 2018
Multiple Hypermetabolic Subcutaneous Lesions From Hidradenitis Suppurativa Mimicking Metastases on 18F-FDG PET/CT
Describes a skin disease, not pimple causes.Case seriesVery low qualityRelated question
1 people2018
the hidradenitis suppurativa lesions (including in the buttocks) lit up on the scan and could be mistaken for cancer metastases
Who was studied
a 64-year-old man with vocal cord cancer being scanned for staging, who also had hidradenitis suppurativa
What they received
none - this was an imaging case report, not a treatment study
Main outcome
whether skin lesions from hidradenitis suppurativa could be mistaken for cancer spread on PET/CT scan
Quality
this is a single patient case report describing an imaging finding, not a treatment or causal study, so it carries very little weight for explaining why pimples occur.
Limitations
only one patient; describes an imaging pitfall rather than investigating causes or treatment of buttock lesions; not generalizable.
Taken word for word from the abstract
- population We describe a case of a 64-year-old man presenting for F-FDG PET/CT for staging of a left vocal cord squamous cell carcinoma.
- n We describe a case of a 64-year-old man
- intervention F-FDG PET/CT
- primaryOutcome This case illustrates an unusual inflammatory cause of F-FDG incidental uptake that should not be mistaken for metastases.
- result The scan showed uptake in the left vocal cord malignancy and multiple hypermetabolic subcutaneous foci in the right axilla, right buttocks, and scalp in known locations of skin lesions related to hidradenitis suppurativa.
Clin Nucl Med · PMID 29166335 · Read it on PubMed ↗
Sehgal et al. 2017
Hidradenitis Suppurativa and Concomitant Down Syndrome: Literature Review of Other Associated Mucocutaneous Manifestations in Adults
Describes rare skin disease, not typical acne.Case seriesVery low qualityRelated question
size not given2017
describes hidradenitis suppurativa lesions on inner thighs, groin, and buttocks along with other associated skin conditions in Down syndrome patients
Who was studied
adults with Down syndrome
What they received
none (observational description)
Compared with
none
Main outcome
presence and features of hidradenitis suppurativa and other skin conditions
Quality
This is a case report and literature review describing disease features, not testing a treatment, so it can't show what works or why pimples occur in general.
Limitations
Case report/review of a rare condition in people with Down syndrome, not a study of typical buttock acne in the general population.
Taken word for word from the abstract
- population hidradenitis suppurativa (HS) occurring in Down disease
- intervention This contribution describes hidradenitis suppurativa (HS) occurring in Down disease that presented with morphology conforming to an overlap of stages 1 and 2 of the Hurley staging system
- comparator the clinical and pathognomonic features of several other concomitant diseases are defined and reviewed
- primaryOutcome the formation of solitary or multiple isolated abscesses without scarring or sinus tracts, recurrent abscesses, and single or multiple widely separated lesions with sinus tract formation, occupying apocrine sweat gland-bearing areas: the inner thighs, groin, and buttocks
- result The lesions were bilateral and symmetrical, of rare occurrence.
Skinmed · PMID 28859733 · Read it on PubMed ↗
Arenbergerová et al. 2017
[Hidradenitis suppurativa - symptoms, diagnostics, and therapy]
Explains hidradenitis suppurativa as a cause.Narrative reviewLow qualityRelated question
size not given2017
the abstract describes the disease process and treatment options without reporting a specific trial result
Who was studied
people with hidradenitis suppurativa, a chronic skin condition affecting areas with hair follicles and sweat glands
What they received
various treatments including topical antiseptics, antibiotics, TNF-α antagonists, and surgery
Main outcome
description of symptoms, diagnosis, and treatment approaches rather than a measured outcome
Quality
this is a general descriptive review of the disease, not a study testing or comparing treatments, so it can't show whether any treatment works.
Limitations
no data, statistics, or outcome measures are given; it is a descriptive overview rather than original research.
Taken word for word from the abstract
- population Women are most often affected in the axillary and inguinal parts, while men in the perianal and gluteal areas.
- intervention treatment consists of topical antiseptics, antibiotics or long- term therapy with systemic antibiotics
- intervention In more advanced stages, systemic therapy with TNF-α antagonists is needed.
- intervention Further therapeutic modality is surgical intervention and wide excision of the affected area.
- result Nevertheless, recurrences in the adjacent tissue cannot be avoided.
- primaryOutcome Hidradenitis suppurativa is a chronic skin disorder characterized by recurrent inflammatory nodules, fistulas, abscesses, and scarring
Cas Lek Cesk · PMID 28722455 · Read it on PubMed ↗
Dogan et al. 2017
Childhood-Onset Keratosis Lichenoides Chronica Accompanied by Severe Hair Loss
Rare skin disease caused bumps, not typical pimples.Case seriesVery low qualityRelated question
1 people2017
Diagnosed as keratosis lichenoides chronica based on skin appearance and biopsy findings
Who was studied
A 37-year-old woman with lifelong skin erythema and hyperpigmented papules, now with hair loss
What they received
None (observational case report, skin biopsy performed)
Main outcome
Diagnosis of the skin condition causing papules and plaques, including on the buttocks
Quality
This is a single patient case report, so it cannot show whether this explains most people's buttock pimples or how to treat them.
Limitations
Single case report of a rare chronic skin disease with no treatment or comparison data, not representative of typical buttock pimples (usually acne or folliculitis).
Taken word for word from the abstract
- population A 37-year-old woman attended the dermatology outpatient clinic because of recent hair loss from the eyebrows and axillae.
- population Her past medical history revealed mild generalized erythema and hyperpigmented papules and plaques since childhood.
- intervention One of the lichenoid papules was biopsied.
- primaryOutcome flat-topped, purple to brown hyperkeratotic lichenoid papules and linear plaques on the elbows, trunk, and buttocks
- result Clinicopathologic correlation of the case was consistent with keratosis lichenoides chronica (KLC).
- n A 37-year-old woman
Skinmed · PMID 28705285 · Read it on PubMed ↗
Thorlacius et al. 2018
Severe hidradenitis suppurativa responding to treatment with secukinumab: a case report
One patient's severe boils improved.Case seriesVery low qualityRelated question
1 people12 weeks
After 12 weeks, lesion count dropped from 23 to 7 and pain scores improved
Who was studied
A 47-year-old man with severe hidradenitis suppurativa affecting the neck, armpits, breasts, genital skin and buttocks
What they received
Secukinumab (an antibody drug that blocks interleukin-17A)
Compared with
No comparator; before-and-after treatment in the same patient
Main outcome
Number of skin lesions and pain scores reported by the patient
Quality
This is a single patient case report with no comparison group, so it cannot reliably show the drug caused the improvement.
Limitations
Only one patient was studied, there was no control group, and improvement could be due to other factors or natural fluctuation of the disease.
Taken word for word from the abstract
- n a case of a 47-year-old man
- population Hurley stage III lesions on the neck, axillae, breasts, genital skin and buttocks
- intervention Secukinumab is an IL-17A monoclonal antibody, which binds to IL-17A and inhibits the cytokine interaction with the IL-17 receptors
- comparator who had experienced only temporary benefit from different medical treatments over several years
- primaryOutcome the number of lesions reported by the patient within the period of the last 4 weeks
- result After 12 weeks of treatment with secukinumab, the number of lesions reported by the patient within the period of the last 4 weeks was reduced from 23 to seven
Br J Dermatol · PMID 28654150 · Read it on PubMed ↗
Posch et al. 2017
The role of wide local excision for the treatment of severe hidradenitis suppurativa (Hurley grade III): Retrospective analysis of 74 patients
Surgery improved quality of life in severe HSRetrospectiveLow qualityRelated question
74 people2017
quality of life scores improved significantly after surgery
Who was studied
patients with severe hidradenitis suppurativa (a chronic skin condition), mostly affecting the groin and buttock area
What they received
wide local excision surgery to remove affected skin
Compared with
before versus after surgery in the same patients
Main outcome
quality of life measured by a skin disease questionnaire
Quality
This was a look-back study with no comparison group, so it can't prove the surgery itself caused the improvement.
Limitations
The retrospective nature of the study was a limitation.
Taken word for word from the abstract
- n Seventy-four patients were enrolled.
- population Most patients had inguinogenital/gluteal disease (68.9%, P < .001).
- intervention the impact of wide local excision on quality of life in HS Hurley grade III patients
- comparator Wide local excision improved Dermatology Life Quality Index scores from initially 27.89 to 5.31 after surgery (P < .001)
- primaryOutcome Outcome measures included Dermatology Life Quality Index responses
- result Wide local excision improved Dermatology Life Quality Index scores from initially 27.89 to 5.31 after surgery (P < .001)
- limitations The retrospective nature of the study was a limitation.
J Am Acad Dermatol · PMID 28377030 · Read it on PubMed ↗
Fabbrocini et al. 2017
Squamous cell carcinoma arising in long-standing hidradenitis suppurativa: An overlooked facet of the immunocompromised district
Long-term boils can rarely turn cancerous.Narrative reviewVery low qualityRelated question
90 people2017
over 90 reported cases of squamous cell carcinoma developing in long-standing hidradenitis suppurativa, mostly on the perineal or buttock areas
Who was studied
people with long-standing hidradenitis suppurativa (a chronic skin condition causing boils/abscesses, often in buttock and groin areas)
What they received
having long-standing hidradenitis suppurativa
Main outcome
development of squamous cell carcinoma (a type of skin cancer) at the affected skin sites
Quality
this is a narrative literature review of collected case reports, not a controlled study, so it cannot show how common this is or prove cause and effect.
Limitations
The abstract does not describe a systematic search method, control group, or statistical analysis; it is based on compiled case reports and a theoretical concept.
Taken word for word from the abstract
- population patients with hidradenitis suppurativa
- intervention longstanding hidradenitis suppurativa
- primaryOutcome squamous cell carcinoma
- result we were able to identify over 90 cases of patients with hidradenitis suppurativa developing squamous cell carcinoma. Most squamous cell carcinomas appear on the perineal or buttock areas.
- n over 90 cases
Clin Dermatol · PMID 28274364 · Read it on PubMed ↗
Huang et al. 2017
Successful surgical treatment for squamous cell carcinoma arising from hidradenitis suppurativa: A case report and literature review
Surgery cured rare HS-linked skin cancer.Case seriesVery low qualityRelated question
1 people1-year follow-up
no cancer recurrence one year after surgery
Who was studied
a man with long-term hidradenitis suppurativa who developed skin cancer on the buttock
What they received
surgical removal of the cancer followed by skin grafting
Compared with
no comparison group (single patient case report)
Main outcome
whether the cancer came back after surgery
Quality
This is a report of just one patient, so it cannot show how common or typical this problem is.
Limitations
Single case report with only one year of follow-up, reviewing prior literature rather than new systematic data.
Taken word for word from the abstract
- n a 60-year-old male who developed SCC on the right buttock after suffering from HS for 15 years
- population a 60-year-old male who developed SCC on the right buttock after suffering from HS for 15 years
- intervention Radical resection with clear margin was performed, after which topical negative pressure (TNP) was applied followed by split-thickness skin grafting.
- comparator Here we reported a 60-year-old male who developed SCC on the right buttock after suffering from HS for 15 years.
- primaryOutcome In a 1-year follow-up, there was no recurrence of malignancy.
- result In a 1-year follow-up, there was no recurrence of malignancy.
- followUp In a 1-year follow-up, there was no recurrence of malignancy.
Medicine (Baltimore) · PMID 28099342 · Read it on PubMed ↗
Suárez Valladares et al. 2017
Treatment of hidradenitis suppurativa with intralesional photodynamic therapy with 5-aminolevulinic acid and 630nm laser beam
Mostly cleared HS lesions with treatment.Case seriesLow qualityRelated question
38 people2017
24.5 point reduction in severity score and complete response in most treated areas, including 88.9% of buttock lesions
Who was studied
patients with hidradenitis suppurativa (a chronic inflammatory skin condition), treated between 2011 and 2015
What they received
intralesional photodynamic therapy using 5-aminolevulinic acid and light treatment
Compared with
no comparison group; before-and-after results in the same patients
Main outcome
change in disease severity score and complete response of treated areas
Quality
This was a small case series without a comparison group, so it cannot prove the treatment itself caused the improvement.
Limitations
No control group, and this study is about hidradenitis suppurativa, a specific chronic condition, not general pimples or acne on the buttocks.
Taken word for word from the abstract
- n Case series of 38 HS patients treated with I-PDT between 2011-2015
- population Case series of 38 HS patients treated with I-PDT between 2011-2015
- intervention To evaluate the effectiveness, safety and tolerability of intralesional photodynamic therapy (I-PDT) in the management of HS.
- comparator Case series of 38 HS patients treated with I-PDT between 2011-2015 following a standardized protocol to assess response at the treated areas
- primaryOutcome To evaluate the effectiveness, safety and tolerability of intralesional photodynamic therapy (I-PDT) in the management of HS.
- result Difference between basal (median 28.5) and final (0) Hidradenitis Severity Score showed a significant reduction of 24.5 points (p<0.001, 95% OR 19.5-31).
- result Complete response was achieved in 68.2% of armpits, 88.5% of groins, 88.9% of buttocks and 100% of other locations.
J Dermatol Sci · PMID 28034606 · Read it on PubMed ↗
Zhou et al. 2016
Novel Mutations in PSENEN Gene in Two Chinese Acne Inversa Families Manifested as Familial Multiple Comedones and Dowling-Degos Disease
Found genetic cause, not a treatment answer.Case seriesVery low qualityRelated question
2 people2016
Two novel mutations found in the PSENEN gene
Who was studied
Two Chinese families with acne inversa (hidradenitis suppurativa) showing comedones, scars, and nodules on face, neck, trunk, axilla, buttocks, upper arms, thighs
What they received
Genetic mutation analysis of γ-secretase genes (PSENEN, PSEN1, NCSTN)
Main outcome
Identification of specific gene mutations causing the disease
Quality
This is a tiny genetic case study of two families, not a treatment trial, so it says nothing about what works.
Limitations
Only two families studied; no treatment tested; genetic finding only.
Taken word for word from the abstract
- population All the affected individuals in the two families mainly manifested with multiple comedones, pitted scars, and a few inflammatory nodules on their face, neck, trunk, axilla, buttocks, upper arms, and thighs.
- intervention Molecular mutation analysis of γ-secretase genes including PSENEN, PSEN1, and NCSTN was performed by polymerase chain reaction and direct DNA sequencing.
- primaryOutcome This study was aimed to identify the specific mutations in the γ-secretase genes in two Chinese families with AI.
- result Two novel mutations of PSENEN gene were identified, including a heterozygous missense mutation c.194T>G (p.L65R) and a splice site mutation c.167-2A>G.
- n In this study, two Chinese families with AI were investigated.
Chin Med J (Engl) · PMID 27900998 · Read it on PubMed ↗
Jourabchi et al. 2017
Squamous cell carcinoma complicating a chronic lesion of hidradenitis suppurativa: a case report and review of the literature
Rare cancer in chronic skin boils.Case seriesVery low qualityRelated question
80 people4 years
Treatment approach was based on one patient's case plus a review of 80 other reported cases; the abstract recommends aggressive surgery, lymph node checks and possible radiation, but does not report success rates
Who was studied
people with hidradenitis suppurativa (a chronic skin condition causing boil-like lumps) that turned into skin cancer
What they received
aggressive surgical removal plus possible radiation therapy for the cancer
Compared with
not stated
Main outcome
how well treatment controlled the cancer and prevented recurrence or death
Quality
This is a single case report combined with a review of past cases, not a controlled study, so it cannot show whether treatments actually work.
Limitations
Based on one patient and a literature review of case reports, not a controlled study; no statistics on treatment outcomes given.
Taken word for word from the abstract
- population a case of HS of the perineum and buttocks complicated by SCC
- n 80 cases of SCC complicating HS found in the English literature
- intervention large and deep surgical excision, sentinel lymph node evaluation, consultation with radiation oncology for potential adjuvant radiation therapy and close surveillance
- comparator Adjuvant radiotherapy was withheld initially because of concern for poor healing of the surgical wound but was eventually initiated after a second recurrence was identified
- primaryOutcome management has not been standardised or optimised
- result We recommend an aggressive approach to management at the time of SCC diagnosis in HS
- followUp The patient ultimately expired 4 years after the initial diagnosis of SCC
Int Wound J · PMID 27681476 · Read it on PubMed ↗
Veasey et al. 2016
Porokeratosis ptychotropica: a rare manifestation with typical histological exam
Rare skin disorder causing buttock patches.Case seriesVery low qualityRelated question
1 people2016
the condition was identified as porokeratosis ptychotropica, a rare variant of porokeratosis, confirmed by skin biopsy
Who was studied
healthy adult male with long-standing thick scaly patches on the buttocks
What they received
none (diagnostic case report)
Compared with
none
Main outcome
correct diagnosis of the skin condition via clinical exam, dermoscopy, and biopsy
Quality
this is a single patient case report, so it cannot show whether any treatment works or how common this cause is
Limitations
only one patient described; no treatment tested; diagnosis took 22 years and multiple doctors before confirmation
Taken word for word from the abstract
- n the case of a healthy male presenting gluteal hyperkeratotic plaques for 22 years
- population a healthy male presenting gluteal hyperkeratotic plaques for 22 years
- intervention We present a typical clinical presentation and its dermoscopy findings, in addition to histological examination that confirmed the diagnosis.
- comparator None of them had achieved a definitive diagnosis.
- primaryOutcome histological examination that confirmed the diagnosis
- result a verrucous form resembling psoriasis involving the gluteal cleft presenting on the histological exam multiple cornoid lamellae
An Bras Dermatol · PMID 27579746 · Read it on PubMed ↗
Ursani et al. 2016
Pyogenic Arthritis, Pyoderma Gangrenosum, Acne, Suppurative Hidradenitis (PA-PASH) Syndrome: An Atypical Presentation of a Rare Syndrome
Steroids healed ulcers in rare syndrome.Case seriesVery low qualityRelated question
1 people4 weeks
ulcers healed within 4 weeks and diarrhea resolved after steroid treatment
Who was studied
a 44-year-old man with a rare autoinflammatory syndrome affecting joints, skin, and sweat glands
What they received
treatment with prednisone (steroid)
Compared with
no comparator; single patient before and after treatment
Main outcome
healing of painful skin ulcers and resolution of chronic diarrhea
Quality
This is a single unusual patient case report, so it cannot show what causes typical buttock pimples or whether treatment works generally.
Limitations
Single case report of a rare syndrome with ulcers and arthritis, not common acne; no control group; findings may not generalize.
Taken word for word from the abstract
- population A 44-year-old African American male with history of pyogenic arthritis, acne, suppurative hidradenitis, and chronic diarrhea
- intervention After treatment with prednisone, the ulcers healed within 4 weeks
- comparator CASE REPORT A 44-year-old African American male
- primaryOutcome presented for evaluation of painful ulcers located on the bilateral lower extremities, bilateral proximal interphalangeal joints, buttocks, and scrotum, and chronic diarrhea
- result After treatment with prednisone, the ulcers healed within 4 weeks, and the chronic diarrhea resolved.
- n A 44-year-old African American male
Am J Case Rep · PMID 27530224 · Read it on PubMed ↗
Kohorst et al. 2016
Surgical Management of Hidradenitis Suppurativa: Outcomes of 590 Consecutive Patients
Surgery often cured severe hidradenitis suppurativa.RetrospectiveLow qualityRelated question
590 people2016
24.4% had recurrence after surgery, 11.7% needed reoperation, and 2.5% had complications; excision and unroofing were effective with low recurrence
Who was studied
patients with hidradenitis suppurativa, mostly severe (Hurley Stage III) disease, treated surgically
What they received
surgical treatment (excision, unroofing, or drainage) of hidradenitis suppurativa lesions
Compared with
different surgical procedure types compared with each other (excision vs unroofing vs drainage)
Main outcome
postoperative complications and disease recurrence after surgery
Quality
This is a retrospective review of one group of surgical patients with no comparison to non-surgical treatment, so it can't prove surgery is better than other options.
Limitations
Retrospective design, no control/comparison group, and focuses on a specific chronic skin disease (hidradenitis suppurativa) rather than typical causes of buttock pimples.
Taken word for word from the abstract
- n Retrospective review of outcomes of 590 consecutive surgically treated patients.
- population Hurley Stage III disease (476 [80.7%])
- intervention Procedure types were excision (405 [68.6%]), unroofing (168 [28.5%]), and drainage (17 [2.9%])
- comparator Recurrence risk was increased by younger age (hazard ratio [HR], 0.8; 95% confidence interval [CI], 0.7-0.9), multiple surgical sites (HR, 1.6; 95% CI, 1.1-2.5), and drainage-type procedures (HR, 3.5; 95% CI, 1.2-10.7).
- primaryOutcome Postoperative complications occurred in 15 patients (2.5%) and one-fourth (144 [24.4%]) suffered postoperative recurrence
- result Excision and unroofing procedures were effective treatments with infrequent complications and low recurrence rates.
Dermatol Surg · PMID 27340739 · Read it on PubMed ↗
Tokunaga et al. 2015
Clinical Role of Modified Seton Procedure and Coring Out for Treatment of Complex Anal Fistulas Associated With Hidradenitis Suppurativa
Surgery cured severe hidradenitis fistulas.Case seriesVery low qualityRelated question
10 people6 to 8 months
all 10 patients recovered with no recurrence or complications after surgery
Who was studied
10 men aged 32 to 54 with complex anal fistulas and hidradenitis suppurativa causing discharge in the buttocks and thigh
What they received
modified seton procedure combined with coring out of hidradenitis suppurativa tissue
Compared with
none; no comparison group
Main outcome
recurrence of fistula/discharge and healing after surgery
Quality
Only 10 patients were treated with no comparison group, so it can't show whether the surgery is better than other options.
Limitations
Very small case series (n=10) with no control group, describing a specific severe surgical condition rather than typical mild buttock pimples.
Taken word for word from the abstract
- population a total of 10 males (ranging in age from 32 to 54 years) complained of recurrent purulent discharge in the buttocks and thigh regions
- intervention underwent surgical operation according to a modified seton procedure for complex anal fistulas and coring out for hidradenitis suppurativa
- comparator A variety of techniques have been described to treat complex anal fistulas.
- primaryOutcome to remove the external fistula tract to prevent recurrence while ensuring fecal continence
- result They have been well without any morbidities or recurrence.
- n a total of 10 males (ranging in age from 32 to 54 years)
Int Surg · PMID 26414817 · Read it on PubMed ↗
Shaw et al. 2015
A case of perforating folliculitis in association with antisynthetase syndrome
Rare skin condition tied to autoimmune disease.Case seriesVery low qualityRelated question
1 people2015
the abstract describes a single case where follicular bump-like skin lesions (perforating folliculitis) occurred in a patient who already had antisynthetase syndrome, an autoimmune condition
Who was studied
a person with antisynthetase syndrome (a rare autoimmune muscle/lung disease) who developed a skin condition
What they received
none - this is a description of a skin condition (perforating folliculitis), not a treatment
Compared with
none
Main outcome
description of the skin condition and its association with underlying disease
Quality
this is a report of just one patient, so it cannot show whether this applies to other people or what causes typical buttock pimples.
Limitations
single case report; no comparison group; describes a rare skin condition linked to a specific autoimmune disease, not common acne-like buttock pimples
Taken word for word from the abstract
- n In this report, we describe an instance of PF that arose in the setting of preexisting antisynthetase syndrome.
- population preexisting antisynthetase syndrome
- primaryOutcome Perforating folliculitis (PF) describes the process by which altered dermal material is eliminated from the epidermis through a follicular unit resulting in keratotic, follicular papules that favor hair-bearing regions of the forearms, arms, buttocks, and thighs.
- result In this report, we describe an instance of PF that arose in the setting of preexisting antisynthetase syndrome.
- intervention Perforating folliculitis (PF) describes the process by which altered dermal material is eliminated from the epidermis through a follicular unit
- comparator Diabetes mellitus (DM) and chronic renal failure (CRF) are commonly associated with PF.
J Biol Regul Homeost Agents · PMID 26016976 · Read it on PubMed ↗
Zhu et al. 2014
Unilateral generalized keratosis pilaris following pregnancy
One case, pregnancy-linked skin bumps.Case seriesVery low qualityRelated question
1 people2014
she developed widespread keratosis pilaris on one side of her body during early pregnancy
Who was studied
a 29-year-old woman in the second month of her second pregnancy
What they received
none (observational case report)
Main outcome
development and extent of keratosis pilaris skin bumps
Quality
This is a single patient case report, so it cannot show what causes or helps most people with this condition.
Limitations
Single case report; no control group; cause is speculative (genetic and hormonal factors suggested but not proven).
Taken word for word from the abstract
- population We report the case of a 29-year-old woman with unilateral generalized KP in the second month of her second pregnancy.
- primaryOutcome the development and progress of unilateral generalized KP in this patient
- result We report the case of a 29-year-old woman with unilateral generalized KP in the second month of her second pregnancy.
- n a 29-year-old woman
- intervention Both a genetic mutation and pregnancy-induced hormonal changes played possible roles in the development and progress of unilateral generalized KP in this patient.
Cutis · PMID 25372256 · Read it on PubMed ↗
Micheletti 2014
Natural history, presentation, and diagnosis of hidradenitis suppurativa
Describes how this skin condition progresses untreated.Narrative reviewLow quality
size not given2014
Describes how the condition starts with small bumps and worsens over time into painful lumps, draining fluid, and scarring if untreated
Who was studied
people with hidradenitis suppurativa (a chronic skin condition affecting areas like armpits, groin, and buttocks)
What they received
none (describes natural course and diagnosis)
Main outcome
how the condition develops and is diagnosed over time
Quality
This is a descriptive review of disease features, not a study testing a treatment or comparing outcomes.
Limitations
No original data, treatment comparison, or outcome measurement reported; purely descriptive of disease course and diagnosis.
Taken word for word from the abstract
- population The anatomic sites of involvement include the axillae (most common), groin, and buttocks, and the perianal, perineal, and mammary regions.
- primaryOutcome the natural history of HS is chronic and progressive
- result More painful subcutaneous nodules form, which rupture and drain a thick, mucopurulent, foul-smelling fluid.
- intervention Without intervention, the natural history of HS is chronic and progressive.
Semin Cutan Med Surg · PMID 25188458 · Read it on PubMed ↗
Schrader et al. 2014
Hidradenitis suppurativa: a retrospective study of 846 Dutch patients to identify factors associated with disease severity
Buttock pimples linked to hidradenitis, not acne.RetrospectiveLow qualityRelated question
846 people2014
Worse disease was linked to being male, longer disease duration, higher body weight, smoking, and lesions in armpit, perianal, and breast areas; men more often had lesions on the buttocks, perianal area, and a history of severe acne; women had earlier onset and more often had family members with the disease
Who was studied
Dutch patients with hidradenitis suppurativa, a chronic skin disease
Main outcome
factors linked to how severe the disease is, and differences by sex and family history
Quality
This is a backward-looking study without a comparison treatment, some information was self-reported by patients, and it only shows associations, not causes.
Limitations
Some parameters were patient-reported.
Taken word for word from the abstract
- n 846 consecutive Dutch patients with hidradenitis suppurativa
- population 846 consecutive Dutch patients with hidradenitis suppurativa
- primaryOutcome We sought to identify disease-related factors associated with severity, sex, and family history.
- result Severity was associated with male sex (OR 2.11; P < .001), disease duration (OR 1.03; P < .001), body mass index (OR 1.03; P = .01), smoking pack-years (OR 1.02; P = .001), and axillary (OR 2.24; P < .001), perianal (OR 1.92; P < .001), and mammary lesions (OR 1.48; P = .03).
- result Men more commonly had gluteal, perianal, and atypical lesions, and a history of severe acne.
- result Women had earlier onset, more inguinal and mammary lesions, and more frequent family history for hidradenitis suppurativa.
- limitations Some parameters were patient-reported.
J Am Acad Dermatol · PMID 24880664 · Read it on PubMed ↗
Scheinfeld 2014
An atlas of the morphological manifestations of hidradenitis suppurativa
Describes skin condition causing buttock bumps/scarringNarrative reviewVery low qualityRelated question
size not given2014
many different lesion types were described, including scarring folliculitis of the buttocks, boils, cysts, and sinus tracts, suggesting HS is a 'reaction pattern' with varied appearances
Who was studied
people with hidradenitis suppurativa, a skin condition
What they received
none - this is a descriptive atlas of skin lesion appearances, not a treatment study
Main outcome
the different ways hidradenitis suppurativa can look on the skin, including on the buttocks
Quality
this is just a descriptive picture atlas of skin findings, not a controlled study comparing treatments or outcomes.
Limitations
no patient numbers, no comparison group, no quantitative data - purely descriptive atlas of appearances
Taken word for word from the abstract
- population This article is dermatological atlas of the morphologic presentations of Hidradenitis Suppurativa (HS).
- primaryOutcome In sum, the variety of presentations of HS as shown by these images supports the supposition that HS is a reaction pattern.
- result scarring folliculitis of the buttocks (from mild to cigarette-like scarring)
- result In sum, the variety of presentations of HS as shown by these images supports the supposition that HS is a reaction pattern.
- intervention This article is dermatological atlas of the morphologic presentations of Hidradenitis Suppurativa (HS).
Dermatol Online J · PMID 24746309 · Read it on PubMed ↗
Scheinfeld 2014
A case of a patient with stage III familial hidradenitis suppurativa treated with 3 courses of infliximab and died of metastatic squamous cell carcinoma
Severe long-term disease turned into fatal skin cancer.Case seriesVery low qualityRelated question
1 people11 months after the infliximab was started
squamous cell carcinoma was found after the third infliximab-and-debridement course, it had already spread (metastasized), and the patient died
Who was studied
a 47-year-old man with long-standing, familial, severe (stage III) hidradenitis suppurativa affecting the groin, legs, buttocks, and perineal areas
What they received
infliximab (3 courses, 500mg) plus surgical debridement
Compared with
none; no comparison group, this is a single patient's treatment course
Main outcome
development of skin cancer (squamous cell carcinoma) and survival
Quality
this is a single patient's case report, so it cannot show whether infliximab caused the harm or how often this happens.
Limitations
only one patient; no control group; cannot separate effects of long-standing untreated disease, infliximab, or other treatments; author notes the disease had already been present for decades before malignant change.
Taken word for word from the abstract
- population A 47-year-old male presented with progressive HS since early adulthood. His stage III hidradenitis suppurativa (HS) involved his groin, legs buttocks, and perineal areas.
- intervention He took 3 courses of infliximab 500mg, each of which was followed by surgical debridement of the perineal and anal areas.
- comparator I report a patient with long standing Hurley Stage III, familial HS, wwho developed metastatic SCC after 3 courses of infliximab and expired 11 months after the infliximab was started.
- primaryOutcome At the 3rd surgical debridement his physician noted the presence of squamous cell carcinoma (SCC) on July 28, 2008.
- result However, the patient developed the patient underwent scanning soon after that showed soon after that the SCC had metastasized. He expired in June of 2009.
- n A 47-year-old male presented with progressive HS since early adulthood.
- followUp expired 11 months after the infliximab was started
Dermatol Online J · PMID 24656278 · Read it on PubMed ↗
Dufour et al. 2014
Hidradenitis suppurativa: a common and burdensome, yet under-recognised, inflammatory skin disease
Chronic skin disease, not acneNarrative reviewLow quality
size not given2014
the abstract describes what the disease looks like, how common it is, and its risk factors, but does not test any treatment or report a benefit/harm outcome
Who was studied
people with hidradenitis suppurativa, a skin condition affecting armpits, groin, breasts and buttocks
Main outcome
description of the disease: symptoms, prevalence, risk factors and burden
Quality
this is a descriptive review summarizing general knowledge about the disease, not a study testing a treatment or measuring an outcome
Limitations
abstract does not report study methodology, sample size, or test any intervention - it is purely descriptive
Taken word for word from the abstract
- population Hidradenitis suppurativa (HS) is a chronic, relapsing, inflammatory skin condition that typically occurs after puberty
- population painful inflamed nodules or boils in the apocrine gland-bearing regions (armpits, genital area, groin, breasts and buttocks/anus)
- primaryOutcome Estimated prevalence is 1-4% worldwide and HS is three times more common in women than men
- result Risk factors include smoking and obesity. Comorbidities include inflammatory bowel disease and spondyloarthropathies.
Postgrad Med J · PMID 24567417 · Read it on PubMed ↗
Samycia et al. 2013
Adalimumab in treatment-resistant hidradenitis suppurativa following recurrence after extensive affected area excision: a review of biologics therapy
Marked improvement with adalimumab in one patient.Case seriesVery low qualityRelated question
1 people2013
adalimumab led to marked improvement after other treatments failed
Who was studied
a man with severe long-term hidradenitis suppurativa in the groin, buttock, and perianal area
What they received
adalimumab (a biologic drug)
Compared with
other treatments tried first: etanercept and infliximab with methotrexate, and surgery
Main outcome
improvement in hidradenitis suppurativa symptoms
Quality
This is a single patient case report plus a non-systematic literature summary, so it cannot reliably show whether the treatment works in general.
Limitations
Single case report; literature review is low-grade evidence without controlled trials; authors note clinical judgment is needed and adverse effects should be watched for.
Taken word for word from the abstract
- population a 48-year-old male with a 15-year history of refractory perianal-inguinal-buttock HS
- intervention marked improvement with adalimumab
- comparator After trialing etanercept and infliximab with methotrexate
- primaryOutcome still had severe pain
- result After trialing many traditional therapies, we found that adalimumab appears to be the most effective treatment modality for our patient.
- n a 48-year-old male
J Cutan Med Surg · PMID 24144253 · Read it on PubMed ↗
Scheinfeld 2013
Hidradenitis suppurativa: A practical review of possible medical treatments based on over 350 hidradenitis patients
Treatment guide for hidradenitis suppurativa, not plain pimples.Narrative reviewLow qualityRelated question
350 people2013
the article summarizes the author's treatment experience and recommends different drug combinations depending on how mild or severe the disease is, without reporting specific success rates
Who was studied
people with hidradenitis suppurativa, a skin condition that can affect the buttocks, armpits, groin and other areas
What they received
various medical treatments such as topical and oral antibiotics, hormone blockers, biologics and other drugs, chosen based on disease stage
Compared with
no formal comparison group; treatments compared based on disease severity and stage
Main outcome
not clearly stated as a measured outcome; the review describes which treatments are used for different severities of hidradenitis suppurativa
Quality
this is one doctor's personal treatment experience and opinion, not a controlled study comparing outcomes.
Limitations
no control group, no statistical outcome data, and it covers hidradenitis suppurativa specifically rather than general buttock pimples
Taken word for word from the abstract
- n This article summarizes my treatment experience with over 350 HS patients.
- population HS most commonly involves cutaneous intertriginous areas, such as the axilla, inner thighs, groin and buttocks, and pendulous breasts
- intervention Topical clindamycin and dapsone are often adequate for treating mild HS.
- comparator Treatment depends on the morphology, extent, severity, and duration.
- primaryOutcome This article summarizes my treatment experience with over 350 HS patients.
- result For Stage 1 and 2 HS, first line treatment combines rifampin with either oral clindamycin or minocycline.
Dermatol Online J · PMID 24021361 · Read it on PubMed ↗
Jianbing et al. 2015
Topical negative pressure coupled with split-thickness skin grafting for the treatment of hidradenitis suppurativa: a case report
Skin healed, no recurrence after grafting.Case seriesVery low qualityRelated question
1 people2-year follow-up
The wound healed after skin grafting, and there was no recurrence of hidradenitis suppurativa over 2 years
Who was studied
A 66-year-old man with hidradenitis suppurativa (chronic skin disease) on the buttocks, who also had diabetes and prior perianal abscesses
What they received
Wound debridement plus topical negative pressure therapy and nutritional support, followed by skin grafting
Compared with
None (single case, no comparison group)
Main outcome
Wound healing and recurrence of hidradenitis suppurativa
Quality
This is a single patient case report, so it cannot show whether this treatment works better than other options or reliably prevents pimples on the buttocks in general.
Limitations
Single case report with no control group, so findings may not generalize; the man had diabetes and severe prior infection, which may not reflect typical cases of buttock pimples.
Taken word for word from the abstract
- n a 66-year-old man who had hidradenitis suppurativa in the buttocks
- population a 66-year-old man who had hidradenitis suppurativa in the buttocks. He suffered from diabetes mellitus.
- intervention After wound debridement treatment, topical negative pressure and nutritional support were given.
- comparator Here, we report the case of a 66-year-old man
- primaryOutcome the wound healed with split-thickness skin grafting
- result In a 2-year follow-up, there was no evidence of hidradenitis suppurativa recurrence.
- followUp In a 2-year follow-up
Int Wound J · PMID 23834292 · Read it on PubMed ↗
Mutaf et al. 2014
Surgical treatment of extensive sacrococcygeal hidradenitis suppurativa with triangular closure technique
Surgery healed severe boils well.Case seriesLow qualityRelated question
16 people36 months (6 months-5 years)
all wounds closed successfully, 2 patients had minor tissue death at flap tip, no infections, no recurrence over follow-up
Who was studied
adults with severe hidradenitis suppurativa (boil-like skin disease) in the tailbone/buttock area
What they received
triangular skin flap surgery to close large wounds after removing diseased tissue
Compared with
none - all patients received the same surgical technique
Main outcome
successful wound closure, complications, and recurrence of disease
Quality
this is a small case series of only 16 patients with no comparison group, so it cannot prove this surgery works better than other options.
Limitations
small sample size, no control group, and this studies a surgical treatment for a specific severe skin disease rather than ordinary pimples
Taken word for word from the abstract
- n in 16 patients (12 men and 4 women)
- population extensive HS of sacrococcygeal region
- intervention triangular closure technique has been used for skin coverage of the large sacrococcygeal defects resulting from excision of the HS
- comparator Here, we present the use of triangular closure technique as a new alternative in surgical treatment
- primaryOutcome In all patients, a successful tension-free closure of the defect was obtained.
- result Except for 2 patients who had tip necrosis, all patients healed uneventfully. There was no patient with infection and wound dehiscence. A mean follow-up for 36 months (6 months-5 years) revealed no recurrence and an aesthetically acceptable scar formation in all patients.
Ann Plast Surg · PMID 23728245 · Read it on PubMed ↗
Bilali et al. 2012
Surgical treatment of chronic hidradenitis suppurativa in the gluteal and perianal regions
Surgery cured most severe cases.Case seriesVery low qualityRelated question
6 people2012
83% of patients healed successfully with no recurrence after surgery, while conservative treatment had little effect
Who was studied
adults with long-term severe hidradenitis suppurativa (boil-like infections) on the buttocks and around the anus
What they received
wide surgical removal of the affected skin
Compared with
non-surgical (conservative) treatment
Main outcome
successful healing without the condition coming back
Quality
Only 6 patients were reviewed retrospectively with no control group, so the findings can't be generalized.
Limitations
Very small retrospective case series without a control group or long-term follow-up reporting.
Taken word for word from the abstract
- n A retrospective review of 6 patients' medical records from January 2001 to December 2010.
- population perianal hidradenitis suppurativa (HS), is a chronic suppurative disease
- population treatment for HS in the gluteal and perianal regions
- intervention surgical excision
- comparator The conservative treatment methods had little effect, particularly on gluteal and perianal/perineal HS.
- primaryOutcome Successful treatment without recurrence was accomplished in 5 (83.3%) of the patients.
- result Successful treatment without recurrence was accomplished in 5 (83.3%) of the patients.
- result The only successful treatment was wide surgical excision.
Acta Chir Iugosl · PMID 23373365 · Read it on PubMed ↗

How we searchedThe exact query, the date it ran, and what came back — so you can run it yourself.

Searched: PubMed · ClinicalTrials.gov · Crossref on 2026-10-13
The exact search — paste this into PubMed to repeat it: ("Folliculitis"[Mesh] OR folliculitis[tiab] OR "Acne Vulgaris"[Mesh] OR "Hidradenitis Suppurativa"[Mesh] OR "Keratosis"[Mesh]) AND (buttock*[tiab] OR gluteal[tiab] OR "natal cleft"[tiab] OR nates[tiab]); PubMed expanded that to: ("Folliculitis"[MeSH Terms] OR "Folliculitis"[Title/Abstract] OR "Acne Vulgaris"[MeSH Terms] OR "Hidradenitis Suppurativa"[MeSH Terms] OR "Keratosis"[MeSH Terms]) AND ("buttock*"[Title/Abstract] OR "gluteal"[Title/Abstract] OR "natal cleft"[Title/Abstract] OR "nates"[Title/Abstract])
What came back: 327 records found · 200 read · 120 answered the question
Included: Human, animal or laboratory studies reporting an outcome relevant to the question
Excluded: Records about a different condition or intervention
Records reporting no outcome
Retracted publications, which are listed but excluded from every count
Limits: Details were read from abstracts, not full papers, so anything reported only in a paper's methods section is not captured here.
Fields were read from abstracts, not full text, so detail reported only in a paper's methods section is not captured.
Evidence strength is adapted from the GRADE framework. It is not a GRADE assessment and was not produced by a GRADE panel.

327records came back from the search
200were read
120actually answered the question

Why people try thisThe reasoning behind the question — not a claim that it works.

Buttock pimples look like facial acne, so people reach for the same scrubs and spot treatments.
They're hidden by clothing and embarrassing, so people self-treat rather than see a doctor.
Tight jeans, gym gear, and sitting all day feel like an obvious cause, so people assume friction and sweat explain everything.
They're easy to blame on 'bad hygiene,' so people scrub harder, which can make irritation worse.

Common questionsShort answers, drawn from the same studies.

Why do I get pimples on my butt?: These studies describe blocked, irritated hair follicles (folliculitis) as a common pattern, often linked to friction, sweat, and tight clothing, but no study measured how often this is the actual cause versus something else. If bumps are painful, keep returning in the same spots, or form tunnels under the skin, that pattern is linked in these studies to hidradenitis suppurativa, a different condition needing medical care.
Why do I keep getting pimples on my butt?: No study tracked a general group of people to see how often buttock pimples come back. But friction from tight clothing or sitting, sweating, and obesity were each linked to more frequent outbreaks in small studies, and bumps that keep returning in the same spot can be a sign of hidradenitis suppurativa rather than ordinary pimples.
Why do I have so many pimples on my butt?: Studies found folliculitis was far more common in children with obesity than in normal-weight children, and heavy sweating or friction (seen in sailors after weeks at sea) was linked to more outbreaks. No study set a number for what counts as 'too many.'
Can you get a pimple in your butt crack?: Yes. Studies describe the fold between the buttocks (the gluteal cleft) as a site for folliculitis, hidradenitis suppurativa, and pilonidal disease, a separate condition involving hair and cysts near the tailbone.
Should I stop treating it like facial acne?: If scrubs or spot treatments aren't helping after a few weeks, stop and see a doctor rather than continuing them. These studies suggest persistent or painful bumps in this area are sometimes a different condition, hidradenitis suppurativa, that doesn't respond to acne treatment and may need antibiotics, biologics, or surgery instead.

This is information, not advice

This page summarises published research. It cannot tell you what is happening in your own body, and evidence changes. If something is bleeding, painful, or new, it is worth being looked at — that is a different question from the one on this page, and a better one to bring to a consultation.

Contact the office

Automated evidence review — PubMed, ClinicalTrials.gov, Crossref. Search strategy, grading rules and the checks that must pass before anything publishes were written by Allen Kamrava, MD, MBA, FACS, FASCRS, colon & rectal surgery, Beverly Hills. The pages themselves are compiled by software running that method and are not read one by one before publication — saying otherwise would be the one claim here that could not be checked.

Allen Kamrava, MD, MBA, FACS, FASCRS · 435 N. Bedford Dr., Suite 308, Beverly Hills, CA 90210 · 424.279.8222

Educational information — not medical advice.