Hidradenitis Suppurativa | Visual Dermatology Atlas

Illustration of the main clinical features of hidradenitis suppurativa, showing recurrent painful inflammatory nodules in typical intertriginous areas, including the axillae, groin, perineal, and inframammary regions. Advanced disease is characterized by

General info +

AKA: Acne inversa / Verneuil disease

• Chronic, recurrent inflammatory disease of the hair follicle characterized by nodules, abscesses, draining tunnels, and scarring in intertriginous areas.
• Predominantly affects the axillary, inguinal, genital/perineal, gluteal, and inframammary regions.
• Pathogenesis primarily involves follicular occlusion, followed by follicular rupture and an intense inflammatory response; HS is not primarily a disorder of apocrine gland obstruction.
• Usually begins after puberty, commonly in young adulthood.
• More common in women.
• A family history is present in a substantial subset of patients.
• Strongly associated with smoking and obesity.
• May be associated with metabolic syndrome, severe acne, pilonidal disease, and inflammatory bowel disease.
• Secondary bacterial infection may occur, but HS is not primarily an infectious disease.
• Can have a profound impact on pain, mobility, sexual health, and quality of life.

Symptoms / presentation +

• Recurrent, painful, deep inflammatory nodules.
• Abscesses may rupture and produce purulent or seropurulent drainage, which may be malodorous.
• Lesions characteristically recur at the same anatomical sites.
• Chronic disease may lead to subcutaneous tunnels (sinus tracts) and permanent scarring.
• Characteristic double-ended or polyporous comedones.
• Pain may be severe or throbbing.
• Diagnosis is supported by the triad of typical lesions + typical distribution + chronicity/recurrence.

Clinical exam +

• Deep, tender inflammatory nodules.
• Deep abscesses.
• Purulent or seropurulent drainage may be present.
• Subcutaneous tunnels / sinus tracts in chronic disease.
• Double-ended comedones +++, a characteristic finding.
• Nodules may coalesce into indurated plaques or masses.
• Hypertrophic, fibrotic, or bridging scars.
• Advanced disease may cause extensive architectural distortion and functional impairment.

HURLEY CLASSIFICATION
• Stage I: one or more abscesses/inflammatory nodules without tunnels or scarring.
• Stage II: recurrent abscesses with tunnels and scarring, with lesions separated by areas of relatively normal skin.
• Stage III: diffuse or near-diffuse involvement with multiple interconnected tunnels and abscesses throughout an anatomical region.

Distribution +

• Axillae +++.
• Inguinal folds +++.
• Genital and perineal/perianal regions.
• Inframammary folds.
• Buttocks and intergluteal region.
• Inner thighs.
• Disease is often bilateral and recurrent at the same sites.

Dermoscopy +

• Dilated follicular openings and double-ended comedones may be visible.
• Keratotic follicular structures.
• Erythematous background in active inflammatory lesions.
• Nonspecific vascular structures may occur.
• Dermoscopy may provide additional information but is not required for diagnosis, which remains primarily clinical.

Diagnostic +

• Primarily a clinical diagnosis.
• Based on three key features: characteristic morphology + typical intertriginous distribution + chronic/recurrent course.
• No specific laboratory test is required in typical disease.
• Bacterial cultures are not routinely required and are mainly indicated when secondary infection is suspected.
• Cutaneous ultrasound may help determine the extent of subcutaneous tunnels, particularly when planning procedures.
• Assess relevant comorbidities, including obesity, smoking, metabolic syndrome, depression/anxiety, and inflammatory bowel disease, when appropriate.

Differential diagnosis +

• Furuncle / furunculosis.
• Bacterial skin abscess.
• Inflamed or ruptured epidermoid cyst.
• Pilonidal disease.
• Perineal/cutaneous Crohn disease with fistulas.
• Lymphogranuloma venereum.
• Scrofuloderma.
• Actinomycosis.
• Other chronic inflammatory or infectious disorders causing abscesses and sinus tracts.

Treatment plan +

• Treatment depends on disease severity, inflammatory activity, tunnels/scarring, and impact on quality of life.
• General measures include smoking cessation, weight management when appropriate, minimizing friction, and avoiding tight clothing.
• Appropriate pain management is an important component of care.
• Mild/localized disease: topical clindamycin 1% may be used, particularly for superficial inflammatory lesions.
• Intralesional triamcinolone may be considered for selected acute, painful inflammatory nodules.
• Mild-to-moderate inflammatory disease: oral tetracyclines, commonly doxycycline, may be used for their anti-inflammatory effect.
• Selected patients may require systemic antibiotic combinations such as clindamycin + rifampin under medical supervision.
• Moderate-to-severe disease: biologic therapy may be indicated; TNF or IL-17 inhibitors are among the available options depending on the patient, local guidelines, and treatment availability.
• Hormonal therapies such as spironolactone or combined oral contraceptives may benefit selected female patients.
• Incision and drainage alone provides temporary relief and has a high recurrence rate; it is generally not definitive HS treatment.
• Recurrent nodules or tunnels: deroofing or targeted surgical excision.
• Extensive scarred disease may require wide surgical excision.
• Isotretinoin is not a standard first-line treatment for HS and has inconsistent efficacy; it may have a role in selected acne-associated phenotypes.
• Psychological support and screening for depression/anxiety are important components of comprehensive management.

References +

DermNet — Hidradenitis suppurativa.
American Academy of Dermatology (AAD) — Hidradenitis suppurativa.
UpToDate — Hidradenitis suppurativa: Management.
North American Clinical Management Guidelines for Hidradenitis Suppurativa.
Bolognia JL, Schaffer JV, Cerroni L. Dermatology. Elsevier.