Hidradenitis suppurativa

Background

Normal dermal anatomy.

• Inflammatory condition involving the apocrine gland-bearing areas of skin, characterized by recurrent painful draining nodules.
• More common in women and black or biracial individuals.
• Rarely occurs before puberty. Peak age of onset is 11–20 yo in women and 21–30 yo in men.

Clinical Features

Hidradenitis suppurativa of armpit

Hidradenitis suppurativa

Armpit with hidradenitis suppurativa.

Infected area of hidradenitis suppurativa with underlying pus.

• Tender, nodular lesions most often in the axillae (can also affect gluteal folds, inframammary areas, perianal area, and pubic/genitofemoral areas)
• Malodorous drainage
• Pruritis
• Burning
• Erythema
• Hyperhidrosis
• Scarring

Differential Diagnosis

• Epidermoid or dermoid cyst
• Inflammatory acne
• Granuloma inguinale
• Lymphogranuloma venereum

Skin and Soft Tissue Infection

• Cellulitis
  • Hand cellulitis
  • Facial cellulitis
  • Orbital cellulitis
• Erysipelas
• Lymphangitis
• Folliculitis
• Hidradenitis suppurativa
• Skin abscess
  • Anorectal abscess
  • Bartholin gland abscess
  • Pilonidal abscess
  • Scrotal abscess
• Necrotizing soft tissue infections
  • Necrotizing fasciitis
  • Necrotizing myositis
  • Necrotizing cellulitis
  • Fournier's gangrene
• Mycobacterium marinum

Look-A-Likes

• Sporotrichosis
• Osteomyelitis
• Deep venous thrombosis
• Pyomyositis
• Purple glove syndrome
• Tuberculosis (tuberculous inflammation of the skin)

Evaluation

• Clinical diagnosis: skin nodules in characteristic sites, may have malodorous drainage
• Diagnosis may be difficult in the ED if single nodule is present.

Management

• Clindamycin 1% topic
• Antibacterial soaps
• Systemic treatments (typically prescribed by specialist): acitretin, finasteride, prednisone
• Incision and drainage should be avoided if possible due to risk of scarring

Disposition

• Discharge with primary care/dermatology followup

See Also

• Abscess
• Cellulitis
• Lymphadenopathy