What is the diagnosis and treatment for an adult patient, possibly with a history of poor hygiene or immunocompromised status, presenting with a chronic disease characterized by clusters of abscesses and lesions in the groin and perineal area, affecting the apocrine glands and follicles?

Hidradenitis Suppurativa (Acne Inversa)

The diagnosis is Hidradenitis Suppurativa (HS), a chronic inflammatory disease of the apocrine glands and hair follicles characterized by painful nodules, abscesses, sinus tracts, and scarring in the groin, perineal, and other intertriginous areas. 1

Diagnostic Criteria

For diagnosis, three criteria must be met: 1

• Typical lesions: Painful nodules, abscesses, sinus tracts (draining tunnels), bridged scars, or open comedones 1
• Typical anatomic sites: Axillae, groin, perineal region, perianal region, infra- and intermammary folds, or buttocks 1, 2
• Chronic and recurrent course: The disease must demonstrate chronicity and recurrence 1

HS is a clinical diagnosis—histopathological confirmation is rarely needed. 1 The pathophysiology centers on follicular occlusion as the primary event, followed by rupture and intense inflammatory response. 1

Disease Severity Assessment

Use the Hurley staging system to classify baseline severity: 1

• Hurley Stage I: Abscess formation (single or multiple) without sinus tracts or scarring
• Hurley Stage II: Recurrent abscesses with sinus tract formation and scarring; single or multiple widely separated lesions
• Hurley Stage III: Diffuse or broad involvement with multiple interconnected sinus tracts and abscesses across the entire area

Critical Differential Diagnoses to Exclude

This presentation is NOT perianal Crohn's disease fistulas, despite similar appearance: 1

• Crohn's perianal disease requires evidence of inflammatory bowel disease (diarrhea, weight loss, abdominal pain, endoscopic findings) 1, 3
• Mandatory screening: Assess for IBD symptoms in all HS patients, as approximately one-third of anorectal abscesses may be associated with Crohn's disease 4, 3

This is NOT simple cryptoglandular anorectal abscess/fistula: 4, 3

• Cryptoglandular disease originates from infected anal glands at the dentate line with a single internal opening 4, 3
• HS involves multiple follicular units across broad anatomic areas without connection to anal crypts 1, 2

Treatment Algorithm

Immediate Management (All Patients)

Lifestyle modifications are foundational and non-negotiable: 1

• Smoking cessation: Nicotine induces follicular plugging and epidermal hyperplasia 1
• Weight management: Obesity increases mechanical friction, sweat retention, and pro-inflammatory cytokines (IL-1β, TNF-α) 1
• Provide patient education materials 1

Screen for comorbidities that significantly impact morbidity and mortality: 1

• Depression and anxiety (profound quality of life impact) 1
• Cardiovascular risk factors: diabetes, hypertension, hyperlipidemia, central obesity 1
• Metabolic syndrome and inflammatory arthritis 5

Medical Treatment by Disease Severity

Mild Disease (Hurley Stage I):

• Topical antiseptics and warm compresses 1
• Oral antibiotics for anti-inflammatory properties (not primarily bactericidal): tetracyclines or combination clindamycin-rifampicin 1, 6

Moderate-to-Severe Disease (Hurley Stage II-III):

• Adalimumab (anti-TNF therapy) is the first FDA-approved systemic therapy for moderate-to-severe HS 1, 5
• NICE criteria for continuing adalimumab: 25% reduction in inflammatory nodules and abscesses with no increase in abscesses or draining sinuses 1
• Alternative biologics now include IL-17 inhibitors (secukinumab, bimekizumab) 5

Acute abscess management:

• Incision and drainage for fluctuant abscesses 4
• Antibiotics are NOT routinely required after adequate drainage in immunocompetent patients 4
• Antibiotics indicated only with: systemic signs (fever >38.5°C, pulse >100), immunocompromised status, extensive cellulitis, or incomplete drainage 1, 4

Surgical Management

Surgery is reserved for: 1

• Hurley Stage III disease with extensive sinus tracts and scarring 1
• Failed medical management 1
• Localized disease amenable to wide excision 1

Pre-operative counseling must cover: 1

• Duration of recovery (often prolonged) 1
• Wound care requirements 1
• Risk of recurrence even after surgery 1

Common Pitfalls to Avoid

Do not treat HS as simple "boils" or recurrent skin infections: 7

• This leads to repeated courses of short-term antibiotics without addressing the underlying inflammatory disease 1, 7
• Short courses of antibiotics do not alter the natural history of HS flares 1

Do not assume bacterial infection is the primary driver: 1, 6

• While bacteria (S. lugdunensis, anaerobes) are frequently cultured from HS lesions, the role is uncertain 1, 6
• Antibiotics likely work through anti-inflammatory mechanisms rather than bactericidal effects 1

Do not delay referral to dermatology: 7

• Early intervention prevents irreversible skin damage, tunnel formation, and morbid scarring 5, 7
• HS profoundly impacts quality of life and requires specialized management 5

Document baseline disease severity using validated instruments: 1

• Hurley stage 1
• Pain score (0-10 numeric rating scale) 1
• Quality of life (DLQI or Skindex) 1