Treatment of MRSA Skin Abscess
Incision and drainage is the primary and often sufficient treatment for MRSA skin abscesses, with antibiotics reserved for specific high-risk situations. 1, 2
Primary Treatment Approach
Perform incision and drainage as the mainstay of therapy for all MRSA skin abscesses. 1, 2 This surgical intervention alone achieves cure rates of at least 90% for simple abscesses without antibiotics. 3 Research in children with culture-proven CA-MRSA abscesses demonstrated that incision and drainage without adjunctive antibiotics was effective for lesions <5 cm in immunocompetent patients. 4
Critical Pitfall to Avoid
Do not attempt ultrasonographically-guided needle aspiration as an alternative—this approach has only 26% success compared to 80% with incision and drainage, and success drops further to 8% when MRSA is present. 5
When to Add Antibiotics
Add antibiotics to incision and drainage when ANY of the following are present: 1, 2
- Severe or extensive disease involving multiple sites of infection
- Rapid progression with associated cellulitis
- Signs of systemic illness (fever, tachycardia, hypotension)
- Comorbidities or immunosuppression (diabetes, HIV, chronic disease)
- Extremes of age (very young or elderly)
- Difficult-to-drain locations (face, hand, genitalia)
- Abscess >5 cm in diameter 4
- Lack of response to incision and drainage alone after 7 days 3
Outpatient Antibiotic Selection
For patients requiring antibiotics, choose from these oral options: 1, 2
First-Line Choices:
- Trimethoprim-sulfamethoxazole (TMP-SMX): 1-2 double-strength tablets twice daily (adults) or 4 mg/kg/dose TMP component twice daily (children) 1, 2
- Doxycycline or minocycline: 100 mg twice daily (avoid in children <8 years and pregnancy) 1, 2
- Clindamycin: 600 mg three times daily (adults) or 10-13 mg/kg/dose every 6-8 hours (children)—ONLY if local resistance rates are <10% 1, 2, 6
Important Consideration:
If you need coverage for both MRSA and beta-hemolytic streptococci (purulent cellulitis with surrounding erythema), either use clindamycin alone OR combine TMP-SMX/tetracycline with a beta-lactam like amoxicillin. 1, 6 TMP-SMX and tetracyclines have poor activity against streptococci when used alone. 2
What NOT to Use:
Never use beta-lactam antibiotics alone (penicillin, amoxicillin, cephalexin) for suspected MRSA—they provide zero MRSA coverage. 2 Do not use rifampin as monotherapy or add it routinely, as resistance develops rapidly without proven benefit. 1, 2
Treatment Duration
- 5-10 days for uncomplicated abscesses with adequate drainage 1, 2
- 7-14 days for complicated infections with systemic symptoms or extensive disease 1, 2
Inpatient Management
Admit for IV antibiotics if: 2
- Systemic toxicity despite oral antibiotics
- Rapidly progressive infection
- Inability to achieve adequate surgical drainage
- Airway compromise risk
IV Antibiotic Options:
- Vancomycin (first-line for hospitalized patients) 1, 2
- Daptomycin 4 mg/kg IV once daily 1, 2
- Linezolid 600 mg IV twice daily 1, 2
- Clindamycin 600 mg IV three times daily (if local resistance <10%) 1
Prevention of Recurrence
For patients with recurrent MRSA abscesses: 2
- Keep draining wounds covered with clean, dry bandages
- Practice regular handwashing with soap and water or alcohol-based gel
- Avoid sharing personal items
- Consider decolonization with nasal mupirocin and chlorhexidine body washes
- Evaluate and potentially treat household contacts if infections persist