What is the appropriate management for a female patient in her late 80s presenting with new onset bilateral lower extremity furunculosis, with lesions of varying size, erythema, purulent drainage, and pain?

Management of Bilateral Lower Extremity Furunculosis in an Elderly Female

For this elderly patient with bilateral lower leg boils showing purulent drainage, the primary treatment is incision and drainage of fluctuant lesions combined with an antibiotic active against MRSA, given the purulent nature and bilateral presentation. 1

Immediate Management

Incision and Drainage

• Incision and drainage is the cornerstone of treatment for furuncles and carbuncles 1
• This should be performed for all large furuncles and any fluctuant lesions
• Culture the purulent drainage to identify the pathogen and guide antibiotic therapy 1

Antibiotic Selection

Given the purulent drainage, antibiotic coverage for MRSA is warranted in addition to drainage 1. The IDSA guidelines specifically recommend MRSA coverage when purulent drainage is present 1.

Oral antibiotic options for MRSA coverage include:

• Trimethoprim-sulfamethoxazole (SMX-TMP)
• Doxycycline
• Clindamycin
• Linezolid (if others fail)

Duration: 5-10 days of antibiotic therapy 1

Critical Assessment for Systemic Involvement

Evaluate for SIRS criteria (temperature >38°C or <36°C, heart rate >90, respiratory rate >24, WBC >12,000 or <4,000) 1:

• If SIRS is present: Consider hospitalization and intravenous antibiotics (vancomycin, daptomycin, or linezolid) 1
• If no SIRS: Outpatient oral therapy is appropriate 1

Special Considerations for Elderly Patients

In this late 80s patient, obtain blood cultures given her age and potential for immunocompromise 1. The guidelines recommend blood cultures in patients with severe cell-mediated immunodeficiency or other compromising conditions, which advanced age may represent.

Adjunctive Measures

Local Care

• Examine interdigital toe spaces carefully for tinea pedis, fissuring, or maceration 1
• Treating toe web abnormalities can eradicate pathogen colonization and reduce recurrence risk 1
• Elevation of the affected legs to promote drainage 1
• Address any underlying venous insufficiency or edema 1

Prevention of Recurrence

Given the bilateral presentation suggesting possible recurrent disease:

Consider a 5-day decolonization regimen 1:

• Intranasal mupirocin twice daily
• Daily chlorhexidine body washes
• Daily washing of towels, sheets, and clothing

For truly recurrent cases after initial treatment, low-dose clindamycin 150 mg daily for 3 months has shown efficacy 2, 3, though this would be a secondary prevention strategy after acute management.

Important Caveats

Avoid Common Pitfalls

• Do not treat as simple cellulitis - the purulent drainage indicates this is furunculosis requiring drainage, not just antibiotics 1
• Do not use beta-lactam monotherapy (like cephalexin alone) when purulent drainage is present, as MRSA coverage is needed 1
• Do not skip drainage - antibiotics alone are insufficient for furuncles and abscesses 1

Rule Out Underlying Conditions

In an elderly patient with new-onset bilateral furunculosis, consider:

• Diabetes mellitus (carbuncles commonly occur in diabetics) 1
• Immunosuppression
• Underlying skin conditions (hidradenitis suppurativa, though less likely with new onset at this age)

When to Hospitalize

Admit if the patient has:

• SIRS or systemic toxicity
• Hemodynamic instability
• Altered mental status
• Concern for deeper or necrotizing infection
• Severe immunocompromise
• Poor adherence capability 1

The bilateral nature and purulent drainage in an elderly patient warrant aggressive initial management with both procedural intervention and appropriate antibiotic coverage, while addressing predisposing factors to prevent recurrence.