Management of MRSA Nasal Colonization
Routine decolonization of asymptomatic MRSA nasal carriers is not recommended; treatment should be reserved for patients with recurrent skin infections despite hygiene measures or documented ongoing household transmission. 1, 2
When Decolonization Is Indicated
Decolonization should only be pursued in these specific scenarios:
- Recurrent skin and soft tissue infections (≥2 episodes at different sites over 6 months) that persist despite optimized wound care and hygiene measures 1, 2
- Ongoing transmission among household members or close contacts despite hygiene interventions 1, 2
- Following treatment of active infection in symptomatic patients, nasal decolonization may be considered 1, 2
- Pre-operative screening in high-risk surgical patients (cardiothoracic, orthopedic procedures) where bundled decolonization plus vancomycin prophylaxis reduces postoperative gram-positive infections 1
Do not pursue decolonization for simple asymptomatic colonization discovered incidentally—this promotes resistance without clinical benefit. 3, 2
Recommended Decolonization Regimen
Standard Protocol
Enhanced Protocol for Recurrent Cases
Combine nasal mupirocin with body decolonization using one of these options:
- Chlorhexidine gluconate 2% body wash daily for 5-14 days 1, 2
- Dilute bleach baths: ¼ cup bleach per ¼ tub (approximately 13 gallons) for 15 minutes twice weekly for up to 3 months 1, 3, 2
The combined approach (mupirocin plus body decolonization) is more effective than mupirocin alone for patients with multi-site colonization. 1
Essential Concurrent Hygiene Measures
Decolonization fails without these interventions—they must be implemented simultaneously:
- Wound management: Keep draining wounds covered with clean, dry bandages 1, 3, 2
- Hand hygiene: Wash hands with soap and water or alcohol-based gel after touching infected areas or contaminated items 1, 3
- Personal items: Avoid sharing or reusing razors, linens, towels, and clothing that contacted infected skin 1, 3
- Environmental cleaning: Focus on high-touch surfaces (counters, doorknobs, bathtubs, toilet seats) using commercial cleaners according to label instructions 1
- Interdigital spaces: Examine and treat toe web maceration, scaling, or fissuring to eliminate colonization reservoirs 1, 2
Household Contact Management
Evaluate all symptomatic household contacts first and treat any active infections before considering decolonization. 1, 3
For asymptomatic household contacts:
- Consider decolonization only when ongoing transmission is documented despite hygiene measures 1, 2
- Treating both patient and household contacts together results in fewer recurrences than treating the patient alone 3, 2
- Use the same decolonization protocol (mupirocin ± body decolonization) for contacts 1
Critical Pitfalls to Avoid
Do not obtain screening cultures before or after decolonization in the absence of active infection. 1, 2 Pre-decolonization cultures are unnecessary if prior MRSA infection was documented, and post-decolonization surveillance cultures are not routinely recommended. 1, 2
Mupirocin resistance is a real concern. High-level mupirocin resistance has been reported in some community settings; prolonged or indiscriminate use promotes resistance without clinical benefit. 1, 3, 2 Reserve mupirocin for appropriate clinical scenarios only.
Recolonization is common. Approximately 40-60% of patients become recolonized within 3 months after decolonization therapy. 3, 4 This is why concurrent hygiene measures and addressing environmental reservoirs are critical.
Evidence limitations: While mupirocin effectively reduces nasal colonization rates, it has not conclusively been shown to prevent infections in community settings. 1, 3, 2 Most benefit has been demonstrated in healthcare settings among surgical patients and dialysis patients. 1
Hospital and Healthcare Settings
For hospitalized MRSA-colonized patients, implement these infection control measures: