Hidradenitis Suppurativa
Hidradenitis suppurativa (HS) is a chronic, inflammatory, recurrent, debilitating skin follicular disease characterized by painful deep-seated, inflamed lesions in apocrine gland-bearing areas of the body, most commonly the axillary, inguinal, and anogenital regions. 1
Clinical Presentation
- HS manifests as double-headed comedones, multiple lesions at different stages of evolution, sinus tracts, and scarring, typically found in intertriginous areas 1
- Lesions are typically located in the dermis and subcutaneous tissue 1
- The disease follows a chronic course with waxing and waning of individual lesions and progression to sinus tracts and scarring over time 1
Epidemiology and Risk Factors
- Prevalence is approximately 1-4% of the population 1, 2
- Female predominance with a 3:1 female to male ratio 1
- Onset typically occurs in the second to fourth decades of life 1
- Strong associations with:
Disease Classification
HS severity is classified using the Hurley staging system 1:
- Stage I: Recurrent nodules and abscesses with minimal scarring
- Stage II: One or a limited number of sinuses and/or scarring within a body region
- Stage III: Multiple or extensive sinuses and/or scarring
Pathogenesis
While the exact pathogenesis is not fully understood, HS is considered a multifactorial disease involving 3:
- Genetic predisposition
- Inflammatory dysregulation
- Environmental modifying factors
- Follicular occlusion with secondary involvement of the apocrine glands 4
Diagnosis
Diagnosis is primarily clinical, based on:
- Characteristic lesions in typical locations
- Chronic and recurrent nature of the disease
- Ultrasound can help differentiate HS lesions from lymph nodes, showing dermal thickening, fluid collections, and tunnel formation 1
- Biopsy is rarely needed but can show follicular hyperkeratosis, hyperplasia, and occlusion 1
Associated Comorbidities
HS is associated with several important comorbidities 1:
- Nearly doubled risk of cardiovascular-associated death
- Type 2 diabetes
- Hyperlipidemia
- Hypertension
- Depression and increased suicide risk
- Inflammatory bowel disease, particularly Crohn's disease
- Spondyloarthropathies 2
Treatment Approaches
Treatment should be tailored to disease severity 1:
Mild Disease (Hurley Stage I)
- Topical clindamycin 1% solution
- Lifestyle modifications (weight management, smoking cessation)
- Pain management with NSAIDs
Moderate Disease (Hurley Stage II)
- Oral tetracyclines
- Combination therapy with clindamycin and rifampicin
- Intralesional steroids for acute flares
Severe Disease (Hurley Stage III)
- Biologic agents, particularly adalimumab (the only FDA-approved biologic for moderate-to-severe HS) 5, 3
- Surgical options including extensive excision for refractory cases
Adalimumab Dosing for HS 5
Adults:
- Day 1: 160 mg (given in one day or split over two consecutive days)
- Day 15: 80 mg
- Day 29 and subsequent doses: 40 mg weekly or 80 mg every other week
Adolescents 12 years and older:
- Weight-based dosing as specified in the FDA label
Common Pitfalls in Management
- Delayed diagnosis due to lack of recognition outside dermatology clinics 2
- Inadequate treatment duration
- Focusing only on acute flares rather than maintenance therapy
- Overlooking associated comorbidities
- Relying solely on medical or surgical therapy instead of a combined approach 1
Impact on Quality of Life
HS significantly impacts quality of life due to 1, 2:
- Intense pain
- Malodorous discharge contributing to social stigma
- Work disability
- Psychological distress and social isolation
Early recognition and appropriate management are crucial to minimize disease progression and improve outcomes in this debilitating condition 1.