What is the best course of treatment for a 23-year-old female patient with a history of scalp folliculitis and vulvar acne, who has recurrent skin and soft tissue infections, including a recent rash with black eschar, and has been previously treated with Linezolid, Doxycycline, and Azithromycin?

Management of Recurrent Skin and Soft Tissue Infections with Black Eschar

This patient requires immediate dermatology consultation and tissue biopsy to rule out necrotizing infection, atypical mycobacterial infection, or fungal infection, given the progression to black eschar despite multiple antibiotic courses. 1

Immediate Diagnostic Workup

The development of black eschar following recurrent boils is a red flag that demands urgent evaluation:

• Obtain tissue biopsy and culture from the eschar site for bacterial (including atypical organisms), fungal, and mycobacterial cultures before initiating further antibiotics 1
• Blood cultures should be obtained if systemic signs are present 1
• Consider imaging (MRI or CT) if there is concern for deeper tissue involvement or necrotizing infection 1

The black eschar suggests either tissue necrosis from necrotizing infection, atypical organisms (Nocardia, Fusarium, Aspergillus), or severe local tissue destruction. 1

Addressing the Pattern of Recurrent Infections

This patient's history reveals a concerning pattern:

• Recurrent folliculitis (scalp and vulvar) suggests possible Staphylococcus aureus colonization or hidradenitis suppurativa 1
• Multiple treatment failures with Linezolid (used twice) indicate either resistant organisms, inadequate source control, or an underlying predisposing condition 1
• HIV status should be assessed given the recurrent nature and severity of infections 1

Key Predisposing Factors to Evaluate:

• Diabetes mellitus (check HbA1c) 1
• Immunosuppression (HIV, immunosuppressive medications) 1
• Hidradenitis suppurativa (given vulvar involvement) 1
• Neutrophil dysfunction disorders 1

Current Antimicrobial Management

While awaiting culture results, empiric broad-spectrum coverage is warranted given the severity:

• Vancomycin 15-20 mg/kg IV every 8-12 hours (targeting MRSA and streptococci) PLUS 1
• Piperacillin-tazobactam 4.5g IV every 6 hours OR imipenem-meropenem 500mg-1g IV every 6-8 hours (covering gram-negative organisms and anaerobes) 1

This combination is recommended for severe skin and soft tissue infections in compromised patients. 1

Important caveat: If tissue biopsy suggests fungal or atypical mycobacterial infection, antifungal therapy (voriconazole or amphotericin B) or antimycobacterial therapy will be required. 1

Surgical Intervention

Surgical debridement should be performed early if there is:

• Necrotic tissue (black eschar) 1
• Concern for necrotizing fasciitis (wooden-hard subcutaneous tissue, rapid progression, systemic toxicity) 1
• Abscess formation requiring drainage 1

The "wooden-hard feel" of subcutaneous tissues distinguishes necrotizing fasciitis from simple cellulitis and requires immediate surgical exploration. 1

Long-Term Prevention Strategy

Once acute infection is controlled, implement decolonization protocol:

• Intranasal mupirocin 2% twice daily for 5 days each month 1
• Chlorhexidine body washes OR dilute bleach baths (1/4-1/2 cup per full bath) for 5 days 1
• Treat household contacts simultaneously to prevent recolonization 1

For recurrent folliculitis specifically:

• Consider oral fusidic acid 500mg three times daily for 2-3 months if S. aureus is confirmed 2
• Alternative: Clindamycin 150mg daily for 3 months has shown efficacy 1
• Azithromycin 250mg three times weekly has been used successfully for suppressive therapy in recurrent staphylococcal infections 3

Treatment Duration and Follow-up

• Intravenous antibiotics should continue until clinical improvement (typically 5-7 days minimum), then transition to oral therapy 1, 4
• Total duration: 2-3 weeks for uncomplicated cases; 6-12 weeks if atypical organisms are identified 1
• Repeat imaging if bacteremia persists to identify undrained foci 1

Critical Pitfalls to Avoid

• Do not assume this is simple recurrent MRSA infection - the black eschar demands investigation for atypical organisms 1
• Do not continue empiric antibiotics without obtaining cultures - this patient has already received multiple courses without success 1
• Do not delay surgical consultation if necrotizing infection is suspected - mortality increases significantly with delayed debridement 1
• Do not overlook underlying immunodeficiency - recurrent severe infections warrant HIV testing and immune function assessment 1

The combination of recurrent folliculitis, treatment-refractory boils, and progression to black eschar suggests either an unusual organism, inadequate source control, or underlying immunocompromise that must be identified and addressed. 1