Hidradenitis Suppurativa

Hidradenitis Suppurativa - Follicle Fury

• Chronic inflammatory skin disease of apocrine gland-rich areas; follicular occlusion is key.
• Patho: Follicular hyperkeratosis & occlusion → rupture → inflammation → sinus tracts, scarring.
• Triggers: Genetics (Notch pathway), smoking, obesity, friction.
• Sites: Axillae, groin, perineal, inframammary regions.
• Lesions: Painful nodules, abscesses, "tombstone" double-comedones, sinus tracts, bridging scars.
• Hurley Staging:
  • I: Abscesses, no sinus tracts/scarring.
  • II: Recurrent abscesses, single/multiple separated sinus tracts, early scarring.
  • III: Diffuse/multiple interconnected tracts & abscesses, extensive scarring.
• Associations: Crohn's disease, spondyloarthropathies, metabolic syndrome.

⭐ HS is strongly associated with smoking; cessation is a crucial part of management.

• Rx: Lifestyle (weight loss, smoking cessation); antibiotics (clindamycin + rifampicin 📌); retinoids; biologics (e.g., adalimumab for moderate-severe); surgery for severe/refractory cases.

Hidradenitis Suppurativa - Lesion Lowdown

• Primary Lesions: Deep, tender, erythematous nodules → painful abscesses.
• Progression & Sequelae: Rupture (malodorous discharge) → chronic sinus tracts (tunnels), fistulae. Heals with hypertrophic "bridge" scars, fibrosis.
• Key Finding: Double-ended or grouped open comedones ("tombstone" comedones).
• Sites: Axillae, inguinal, anogenital, inframammary, buttocks (apocrine areas).
• Diagnosis (Clinical Criteria):
  • Typical lesions: Nodules, abscesses, tracts, scars.
  • Typical distribution: Intertriginous.
  • Chronicity & Recurrence.

• Staging (Hurley System): Assesses severity.
  • I: Abscess(es); no tracts/scarring.
  • II: Recurrent abscesses, tracts & scarring; separated lesions.
  • III: Diffuse; interconnected tracts & abscesses.

⭐ Double-ended comedones: pathognomonic HS clue, not always present.

Hidradenitis Suppurativa - Treatment Toolkit

General Measures: Weight loss, smoking cessation, loose-fitting clothing, local hygiene, pain management.

• Acute Flares:
  • Intralesional corticosteroids
  • Short-course oral antibiotics
  • Incision and drainage (I&D) for fluctuant abscesses (temporary relief, may worsen chronicity)

⭐ Adalimumab is the first FDA-approved biologic for moderate to severe HS (Hurley stage II/III).

• Refractory/Severe Disease:
  • Consider cyclosporine, dapsone, or methotrexate.
  • Surgical options: Deroofing, wide excision, laser ablation ($CO_2$ laser).

Hidradenitis Suppurativa - Scar Stories

• Chronic, relapsing inflammation results in significant, often disfiguring, scarring.
• Scar characteristics:
  • Atrophic (pitted, thin)
  • Hypertrophic (thick, raised, keloid-like)
  • "Bridge" scars: cord-like, fibrotic bands.
  • "Tombstone" comedones: clustered, open comedones within scarred plaques.
• Functional & Structural Complications:
  • Contractures: limiting range of motion, especially in axillae, groin.
  • Chronic pain, even in scarred, inactive areas.
  • Lymphedema: persistent swelling due to lymphatic obstruction.
  • Fistulas, sinus tracts, and anal/urethral strictures.
• Associated Long-term Risks:
  • Anemia of chronic disease.
  • Psychosocial burden: anxiety, depression, impaired quality of life.

⭐ Squamous cell carcinoma (SCC) is a rare but serious complication, arising in chronic HS lesions, particularly in anogenital areas, often after >10-20 years of disease activity or in extensive scarring (Marjolin’s ulcer).

High‑Yield Points - ⚡ Biggest Takeaways

• Hidradenitis Suppurativa (HS): chronic inflammation in apocrine gland-rich areas (axillae, groin, anogenital).
• Features: recurrent painful nodules, abscesses, sinus tracts, and hypertrophic scars.
• Pathogenesis: follicular occlusion is key, not primarily a sweat gland infection.
• Strong associations: smoking, obesity, and family history.
• Severity graded by Hurley staging (Stages I-III).
• Treatment: topical/systemic antibiotics (clindamycin + rifampicin), biologics (adalimumab), and surgery.
• Complication: risk of squamous cell carcinoma (SCC) in chronic, long-standing lesions.