Hidradenitis suppurativa

Hidradenitis suppurativa image

Hidradenitis suppurativa (HS) is chronic scarring inflammatory acne like a disease of the skin bearing apocrine sweat glands. It is also known as Acne Inversa. It commonly involves intertriginous areas of skin like axilla (most common site), inguinal area, and perineal area. It may present as a part of Follicular Tetrad Syndrome which includes Acne conglobata, Hidradenitis suppurativa, dissecting cellulitis of the scalp, and pilonidal sinus.


  • F: M ratio about 3:1
  • Commonly occur in the early twenties with typical range 11-50 years
  • 1-4% prevalent worldwide

What causes Hidradenitis Suppurativa

  • Obesity and metabolic syndrome: 45-80% of patients with HS are overweight
  • Mechanical stress: tight clothing, friction
  • Family history of HS: Present in 35-40%
  • History of Smoking in 60-90% of patients
  • Drugs: Hormonal contraceptives (OCPs, DMPA), Lithium, steroid therapy
  • Other diseases: Crohn’s disease, Diabetes mellitus

Factors not associated with increased risk of HS

  • Shaving
  • Chemical depilatories
  • Deodorants
  • Talcum powder

Pathogenesis of Hidradenitis Suppurativa

Pathogenesis of Hidradenitis Suppurativa

Obstruction of the duct of apocrine sweat gland by keratin→ Dilatation of the duct of gland→ Infection and abscess formation→ Involvement of subcutaneous tissue and adjacent apocrine glands → Fibrosis, scarring, sinus formation → Spread to surrounding tissues

Clinical Features

  • The most common site is axilla. Often it is bilateral.
  • Multiple discharging sinuses, with nodules in the skin which is tender.
  • Induration due to fibrosis.
  • Open and closed comedones
  • Painful firm papules, larger nodules, and pleated ridges
  • Pustules, fluctuant pseudocysts, and abscesses
  • Pyogenic granulomas
  • Draining sinuses linking inflammatory lesions
  • Hypertrophic and atrophic scars


  • Sinus tracts,
  • Comedones, and
  • Scarring— Severe scarring can lead to dense, rope-like bands in the skin with strictures and lymphedema

Hidradenitis suppurativa stages

Hurley Clinical staging for Hidradenitis suppurativa

Differential diagnosis

  • most common differential diagnoses are
    • folliculitis
    • skin abscesses, furuncles (boils), and carbuncles
    • Crohn’s disease (especially perianal lesions)
    • Ulcerative colitis
  • Conditions with lesions similar to hidradenitis suppurativa (HS) include
    • Acne
    • Vulvovaginal fistulae
    • Fistula-in-ano and perianal abscess
  • Rare conditions that may appear similar to hidradenitis suppurativa include
    • cervicofacial actinomycosis, (associated with sinus tract disease)
    • tuberculous lymphadenitis scrofuloderma type of cutaneous tuberculosis
  • Diagnosis is clinical with the presence of recurrent inflammatory nodules, sinus tracts, and hypertrophic scarring in the intertriginous area
  • Laboratory test: Discharge study—culture/sensitivity and AFB.
  • Biopsy to rule out tuberculosis or malignancy.

How to treat Hidradenitis suppurativa

General Management

  • Self-management: treat underlying depression
  • Avoidance of skin trauma
  • Dressings
  • Smoking cessation 
  • Weight management to reduce obesity
  • Antiseptics –Topical antiseptic washes such as chlorhexidine 4% may be helpful for HS.
  • Management of comorbidities 
  • Pain management

Hurley Stage I treatment

  • Topical Clindamycin
  • Intralesional Corticosteroids
  • Punch debridement 

Moderate to severe disease (Hurley stage II and III)

  • Antibiotic therapy 
  • First-line antibiotic therapy
    • Oral tetracyclines
    • Clindamycin and rifampin
    • Other antibiotics — Dapsone,
    • Oral retinoids — Acitretin, isotretinoin, 
  • Surgery — Surgery can be used for the treatment of individual nodules and sinus tract

Refractory moderate to severe disease 

  • TNF-alpha inhibitors 
  • Conventional immunosuppressants 

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  1. https://link.springer.com/article/10.1007/s13671-013-0064-8
  2. Danby FW, Margesson LJ. Hidradenitis suppurativa. Dermatol Clin. 2010;28(4):779‐793. doi:10.1016/j.det.2010.07.003
  3. Image source:https://upload.wikimedia.org/wikipedia/commons/b/b0/Lesions_from_hidradenitis_suppurativa.jpg

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