What is the treatment for a Methicillin-resistant Staphylococcus aureus (MRSA) wound?

Treatment of MRSA Wound Infections

Primary Management: Surgical Intervention First

Surgical debridement and drainage of abscesses is the cornerstone of MRSA wound treatment and must be performed whenever feasible—this is more important than antibiotic selection. 1, 2

• Obtain cultures from purulent drainage before starting antibiotics to confirm MRSA and guide definitive therapy 1, 2
• For simple abscesses or boils, incision and drainage alone may be adequate without antibiotics 1, 2
• Failure to drain abscesses when present leads to treatment failure regardless of antibiotic choice 1

Antibiotic Selection Based on Severity

Non-Severe/Uncomplicated MRSA Wound Infections (Outpatient)

For non-severe MRSA wounds, trimethoprim-sulfamethoxazole (TMP-SMX) 4 mg/kg/dose (TMP component) twice daily is the first-line oral antibiotic. 1, 2

Alternative oral options include:

• Doxycycline 100 mg PO twice daily or minocycline 100 mg PO twice daily 1, 2
• Clindamycin 600 mg orally three times daily—but ONLY if local MRSA resistance rates are <10% 1, 2
• Linezolid 600 mg orally twice daily (highly effective but more expensive) 1, 2

Severe/Complicated MRSA Wound Infections (Inpatient)

For patients with systemic toxicity, rapidly progressive infections, or extensive involvement requiring hospitalization, vancomycin 15-20 mg/kg/dose IV every 8-12 hours is the first-line intravenous option. 2

Alternative IV options include:

• Daptomycin 4-6 mg/kg IV once daily (excellent for complicated skin and soft tissue infections) 1, 2, 3
• Linezolid 600 mg IV twice daily (proven efficacy with 79% cure rate for MRSA skin infections) 1, 4, 5
• Ceftaroline 600 mg IV every 12 hours (newer anti-MRSA cephalosporin) 1

Treatment Duration

Treat uncomplicated MRSA skin infections for 5-10 days, individualized based on clinical response. 1, 2

• Complicated infections require 7-14 days of therapy 1, 2
• Reassess clinically within 48-72 hours to ensure appropriate response 2
• Consider transitioning from IV to oral therapy after clinical improvement and when the patient can tolerate oral medications 1

Special Populations

Pediatric Patients

• IV vancomycin is the preferred agent for children with MRSA infections 1
• Clindamycin 10-13 mg/kg/dose PO every 6-8 hours can be used if the patient is stable and local resistance is <10% 1, 2
• TMP-SMX 4-6 mg/kg/dose (trimethoprim component) PO every 12 hours is an alternative 2
• Tetracyclines (doxycycline, minocycline) should NOT be used in children under 8 years of age 2

Lactating Women

• Clindamycin 600 mg orally three times daily is the preferred first-line treatment for MRSA mastitis 6
• TMP-SMX plus amoxicillin is an alternative, but avoid TMP-SMX in infants younger than 2 months 6

Prevention of Recurrence

For patients with recurrent MRSA infections, implement decolonization with mupirocin (nasal) and chlorhexidine (body). 1

Additional preventive measures:

• Keep draining wounds covered with clean, dry bandages 1, 6, 2
• Maintain rigorous hand hygiene with regular handwashing 1, 6, 2
• Avoid sharing personal items 1
• Evaluate and potentially treat household contacts if recurrent infections persist 1

Critical Pitfalls to Avoid

Beta-lactam antibiotics alone are completely inadequate for MRSA coverage and should never be used as monotherapy. 1

• Do not use rifampin as a single agent or as routine adjunctive therapy for skin infections 1
• Ensure adequate source control—antibiotics cannot compensate for undrained abscesses 1
• Monitor local resistance patterns, particularly for clindamycin (use only if <10% resistance) 1, 2
• For patients with concurrent bacteremia, repeat blood cultures 2-4 days after initial positive cultures to document clearance 1