Hidradenitis Suppurativa: Recognition, Staging, and Management in Primary Care

Hidradenitis suppurativa (HS) is a chronic, relapsing inflammatory follicular disease characterized by painful, deep-seated nodules, abscesses, draining tunnels, double-headed comedones, and scarring in intertriginous areas such as the axillae, groin, perineal/perianal region, inframammary folds, and buttocks.^1,2

Hallmark features include recurrent “boils” that partially improve with antibiotics but return in the same locations, often progressing to persistent tunnels and disfiguring scarring.

HS affects an estimated 0.3%–1% of the population and is more common in women and in individuals with obesity or a history of smoking.^3,4

The disease carries substantial morbidity. Pain, drainage, malodor, and physical deformation contribute to impaired quality of life, social withdrawal, and work disability, and HS is associated with depression, anxiety, metabolic abnormalities, and—in some patients—inflammatory bowel disease.^1,2,5 Early identification in primary care is essential, as diagnostic delays often exceed 7–10 years, and timely staging and referral can reduce cumulative tissue damage and improve long-term outcomes.

Clinicians should suspect HS in patients with recurrent nodules or abscesses in characteristic flexural sites, especially when lesions heal with scars or tunnels, recur despite antibiotics, or cluster alongside risk factors such as smoking or obesity. Recognizing these patterns supports prompt diagnosis and coordination with dermatology before progression to more severe, treatment-resistant disease.

Epidemiology and Risk Factors

HS usually begins after puberty, peaks in young to middle adulthood, and may persist lifelong.^3,4 Women are affected more often than men overall, although anatomic distribution and phenotype can differ by sex.³ Major risk factors include ^1-6:

• Cigarette smoking: strongly associated with HS; odds ratios >10 reported in some cohorts.
• Obesity and metabolic syndrome: higher BMI correlates with disease risk and severity.
• Family history: up to one-third of patients report affected relatives; rare autosomal-dominant forms linked to γ-secretase gene mutations.
• Other associations: inflammatory bowel disease, spondyloarthropathy, polycystic ovary syndrome, depression, and anxiety.

PCP Note: Recognizing these risk clusters can help distinguish HS from recurrent simple infections or folliculitis.

Pathophysiology: Highlights

HS is now understood as a follicular-based autoinflammatory disease, not primarily a disorder of apocrine glands.^1,2,7 Key elements include:

• Follicular occlusion and rupture with keratin plugging and perifollicular inflammation
• Dysregulated innate and adaptive immunity, with elevated TNF-α, IL-1, IL-17, IL-23, and other cytokines in lesional skin and serum
• Microbiome changes: polymicrobial colonization of tunnels and chronic lesions may perpetuate inflammation but is likely secondary, not purely infectious
• Mechanical stress, friction, and maceration in skin folds that promote follicular damage

PCP Note: This framework supports use of biologic agents targeting TNF-α and IL-17 in moderate-to-severe disease.

Clinical Features and Diagnosis

Typical Presentation

Diagnosis is clinical and rests on 3 core criteria⁸:

1. Typical lesions:

• Deep, painful nodules
• Fluctuant abscesses
• Double- or mult-headed comedones
• Draining tunnels (sinus tracts) and rope-like scars

2. Typical locations:

• Axillae
• Inguinal and anogenital/perineal areas
• Inframammary folds
• Buttocks and other intertriginous zones

3. Chronicity/recurrence:

• Recurrent lesions in the same areas (eg, 2+ flares in 6 months)

PCP Note: Primary care clues include a history of “recurrent boils,” multiple courses of antibiotics or incision-and-drainage procedures, and scarring or tunnels on exam.

Staging

The Hurley staging system is simple and widely used^1,3:

• Hurley I: Isolated nodules or abscesses without tunnels or scarring
• Hurley II: Recurrent abscesses with limited tunnels and scarring; lesions separated by normal skin
• Hurley III: Diffuse involvement with interconnected tunnels and extensive scarring across a region

PCP Note: For research and specialized care, the International HS Severity Score System (IHS4) uses lesion counts (nodules, abscesses, tunnels) to quantify severity, but Hurley staging is adequate for most primary-care documentation and referral.

Differential Diagonsis

Consider and distinguish HS from^1,2:

• Recurrent furunculosis/carbuncles
• Infected epidermoid or pilonidal cysts
• Inverse psoriasis, Crohn disease perianal lesions
• Folliculitis, sexually transmitted infections, cutaneous abscesses of other cause

PCP Note: Biopsy is not routinely required but may be useful in atypical presentations or to exclude other conditions.

NEXT: Hidradenitis Suppurativa: When to Suspect, When to Refer

Refererences

1. Sabat R, Alavi A, Wolk K, et al. Hidradenitis suppurativa. Lancet. 2025;405(10476):420-438. doi:10.1016/S0140-6736(24)02475-9

2. Ballard K, Shuman VL. Hidradenitis Suppurativa. In: StatPearls [Internet]. Updated May 6, 2024. Accessed December 15, 2025. https://www.ncbi.nlm.nih.gov/books/NBK534867/

3. Alikhan A, Sayed C, Alavi A, et al. North American clinical management guidelines for hidradenitis suppurativa: Part I. Diagnosis, evaluation, and the use of complementary and procedural management. J Am Acad Dermatol. 2019;81(1):76-90. doi:10.1016/j.jaad.2019.02.067

4. Zouboulis CC, Szepietowski JC, Alavi A, et al. European S2k guidelines for hidradenitis suppurativa/acne inversa: Part 2—Treatment. J Eur Acad Dermatol Venereol. 2025;39(5):899-941. doi:10.1111/jdv.20472

5. Chung CS, Kherallah K, Fragoso NM, et al. Exploring the pathophysiology, burden, and management of hidradenitis suppurativa: a narrative review. Curr Derm Rep. 2025;14(35). doi.org/10.1007/s13671-025-00490-y

6. Kaya G, Ozgen FP, Kelahmedoglu O, et al. Demographic features, clinical characteristics, and comorbidities in hidradenitis suppurativa. Front Med. 2025;12:1499509. doi:10.3389/fmed.2024.1499509

7. Pandey A. Essentials of hidradenitis suppurativa: a comprehensive review of diagnostic and treatment perspectives. Ann Med Surg (Lond). 2024;86(9):5304-5313. doi:10.1097/MS9.0000000000002345

8. Rivera-Díaz J, Rocafort SL, Bonilla IM, Moreda AJ, Cartagena JR. A comprehensive review of hidradenitis suppurativa: from pathogenesis to clinical insights and novel therapeutics. Int J Med Students. 2023;11(3). doi.org/10.5195/ijms.2023.2809