Hidradenitis Suppurativa (HS)

Definition

• Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that affects apocrine gland-bearing areas (e.g. axillae, groin, inframammary regions). It is characterised by recurrent painful nodules, abscesses, sinus tract formation, and scarring, and can significantly impact quality of life.

Symptoms

• Painful, swollen nodules/abscesses, often in body folds

• Purulent or pus-like discharge

• Sinus tract formation leading to chronic draining lesions

• Scarring, tissue destruction over time

• Notable psychological impact (anxiety, depression, social withdrawal)

Assessment: Hurley Staging System

Aetiology & Risk Factors

• Autoinflammatory disorder; precise pathogenesis not fully understood

• Contributory Factors:

  • Friction in areas of tight clothing or skin folds

  • Abnormal immune response to commensal bacteria or follicular occlusion

  • Pro-inflammatory cytokines driving chronic inflammation

  • Secondary bacterial infections can exacerbate flares

  • Certain medications may worsen disease (e.g. lithium, androgens)

Differential Diagnosis

• Acne conglobata

• Folliculitis

• Boils (staphylococcal abscess)

• Dissecting cellulitis of the scalp (similar sinus tract formation but on the scalp)

Management

General Measures

• Loose Clothing, reduce friction in susceptible areas

• Weight loss if overweight or obese (improves friction, reduces inflammatory burden)

• Smoking Cessation: Smoking is a known exacerbating factor

• Pain Management: NSAIDs or paracetamol for mild pain; consider opioids in severe cases short-term

Topical Treatments (Mild Cases)

• Topical Clindamycin 1% lotion BD for up to 3 months

• Benzoyl Peroxide 5% wash once or twice daily

• Possible intralesional corticosteroids for smaller lesions

Oral Antibiotics (Moderate Cases)

• Doxycycline 50–100 mg OD for ≥6 weeks

• Minocycline 50–100 mg OD for ≥6 weeks

• Erythromycin 250–500 mg BD for 6 weeks

• Consider prolonged therapy if improvement is noted

Specialist Treatments (Severe/Recurrent)

• Long-term Oral Antibiotics (e.g. clindamycin + rifampicin)

• Oral Retinoids (e.g. acitretin)

• Biologic Therapy (e.g. adalimumab) – indicated for moderate to severe HS not responding to standard measures

• Surgical interventions: Excision of sinus tracts, unroofing of tunnels, or wider local excisions in advanced disease

Notes

• HS is chronic with a relapsing–remitting course. A multidisciplinary approach (dermatologist, surgeon, mental health support) can be beneficial.

• Psychological support (address depression, low self-esteem) is crucial.

• Lifestyle modifications (smoking cessation, weight reduction) have a significant role in reducing flare frequencyand severity.