What is the recommended treatment for a local spread of Staphylococcus aureus infection, including MRSA?

Treatment of Local Staphylococcus aureus Infections, Including MRSA

For local spread of Staphylococcus aureus infections, including MRSA, the recommended treatment is incision and drainage of abscesses combined with appropriate antibiotic therapy based on local resistance patterns. 1

Initial Management

Surgical Intervention

• Incision and drainage (I&D) is the cornerstone of abscess management and should be performed for all fluctuant lesions 2
• Ensure proper wound care, including cleansing and debridement of any necrotic tissue 2
• Elevate affected limb when possible to promote gravity drainage of edema and inflammatory substances 2

Specimen Collection

• Obtain deep tissue specimens by biopsy or curettage after wound cleansing and debridement 1
• Avoid swab specimens, especially from inadequately debrided wounds, as they provide less accurate results 1
• Send specimens for culture and antimicrobial susceptibility testing prior to starting empiric antibiotic therapy 1

Antibiotic Selection

For Mild to Moderate Infections (No Prior Antibiotic Treatment)

• Target aerobic gram-positive cocci (GPC) with one of the following:
  • Trimethoprim-sulfamethoxazole (not as single agent for cellulitis due to possible Group A Streptococcus) 1
  • Doxycycline (can be used safely in children ≥2 years for <2 weeks) 1
  • Clindamycin (for susceptible isolates) 1
  • First or second-generation cephalosporin (for methicillin-susceptible S. aureus) 1

For Severe Infections or MRSA Risk Factors

• Start broad-spectrum empiric therapy pending culture results 1
• Consider empiric MRSA coverage when:
  • Patient has prior history of MRSA infection
  • Local prevalence of MRSA colonization/infection is high
  • Infection is clinically severe 1
• MRSA treatment options:
  • Vancomycin (IV): First-line for serious MRSA infections 2
    • Target trough concentrations: 15-20 μg/mL for serious infections
    • Weight-based dosing at 15 mg/kg recommended
  • Linezolid (IV/PO): Alternative for skin and skin structure infections 2, 3
  • Daptomycin (IV): For complicated skin infections (not for pneumonia) 2
  • Clindamycin, TMP-SMX, or linezolid (oral options for less severe infections) 2

Treatment Duration

• Uncomplicated skin and soft tissue infections: 5-10 days 2
• Complicated skin and soft tissue infections: 7-14 days 2
• Continue antibiotic therapy until resolution of infection findings, but not through complete wound healing 1
• For soft tissue infections: 1-2 weeks for mild infections, 2-3 weeks for moderate to severe infections 1

Route of Administration

• Parenteral therapy for all severe and some moderate infections, at least initially 1
• Switch to oral agents when the patient is systemically well and culture results are available 1
• Highly bioavailable oral antibiotics alone may be used for most mild and many moderate infections 1
• Topical therapy (mupirocin) may be considered for selected mild superficial infections 1, 2

Special Considerations for Diabetic Foot Infections

• For diabetic foot infections with local spread, incision and drainage plus empiric antibiotic therapy is essential 1
• Consider imaging (plain radiographs initially, MRI if needed) to assess for osteomyelitis 1
• Extend treatment duration if osteomyelitis is present (4-6 weeks) 2

Prevention of Recurrence

• For patients with recurrent infections, consider decolonization protocol:
  • Mupirocin 2% nasal ointment twice daily for 5-10 days 2
  • Chlorhexidine body washes daily for 5-14 days 2
  • Launder clothing, towels, and bedding in hot water 2
  • Avoid sharing personal items (razors, towels) 2

Common Pitfalls to Avoid

• Failure to perform adequate incision and drainage of abscesses 2
• Using trimethoprim-sulfamethoxazole as a single agent for cellulitis (due to possible Group A Streptococcus) 1
• Inadequate dosing of vancomycin (use weight-based dosing at 15 mg/kg) 2
• Neglecting to adjust therapy based on culture and susceptibility results 1
• Continuing antibiotics beyond resolution of infection findings 1
• Failing to implement comprehensive decolonization for recurrent infections 2

By following these guidelines, clinicians can effectively manage local spread of S. aureus infections, including MRSA, while minimizing complications and preventing recurrence.