What is the recommended approach for MRSA (Methicillin-resistant Staphylococcus aureus) decolonization?

MRSA Decolonization Protocol

The recommended approach for MRSA decolonization is a combination of intranasal mupirocin 2% ointment applied twice daily for 5-10 days plus topical antiseptic body decolonization using chlorhexidine washes or dilute bleach baths. 1, 2

Indications for Decolonization

Decolonization should be considered in the following scenarios:

• Patients with recurrent MRSA skin and soft tissue infections (SSTIs) despite optimized wound care and hygiene measures 1
• When ongoing transmission is occurring among household members or other close contacts despite optimizing hygiene measures 1
• Pre-operative decolonization for high-risk surgeries (e.g., orthopedic, cardiac, neurosurgical procedures) 1, 3

Standard Decolonization Protocol

Primary Regimen:

1. Nasal decolonization:

   • Mupirocin 2% ointment applied to anterior nares twice daily for 5-10 days 1, 2
   • A 10-day regimen is superior to shorter regimens, with 89.5% of patients remaining decolonized for at least four weeks 2

2. Body decolonization (choose one):

   • Chlorhexidine gluconate 2-4% body washes daily for 5-14 days 2
   • Dilute bleach baths (1 teaspoon per gallon of water or ¼ cup per ¼ tub) for 15 minutes twice weekly for up to 3 months 1

Additional Measures:

• Focus cleaning on high-touch surfaces (counters, doorknobs, bathtubs, toilet seats) 1
• Use commercially available cleaners according to label instructions 1
• Avoid sharing personal items (razors, towels, linens) 2
• Keep draining wounds covered with clean, dry bandages 2

Enhanced Decolonization for Persistent Colonization

For patients who fail standard decolonization or have multiple body sites colonized:

1. Comprehensive screening of at least 6 body sites (including nose, throat, perianal area, rectum, and inguinal area) to identify all colonization sites 4

2. Site-specific treatment:

   • Intestinal colonization: oral vancomycin 4
   • Urinary tract colonization: cotrimoxazole 4
   • Vaginal colonization: povidone-iodine, chlorhexidine ovula, or octenidine solution 4

3. Combination oral antibiotics (only when topical measures have failed despite good adherence):

   • Rifampin-based combinations (with TMP-SMX or doxycycline) for 5-10 days 2, 5
   • Alternative: oral clindamycin 150 mg daily for 3 months 2

Special Considerations

Pre-operative Decolonization

• Screen patients for MRSA colonization prior to elective procedures, especially high-risk surgeries 1, 3
• Complete decolonization 1-2 weeks before surgery, as recolonization commonly occurs 1
• For MRSA carriers undergoing surgery, consider vancomycin (15 mg/kg 2 hours before surgery) in addition to standard prophylaxis 1

Prevention of Recolonization

• Consider monthly application of mupirocin (5-day course each month) to reduce recurrent infections by approximately 50% 2
• Continue reinforcement of hygiene measures alongside decolonization strategies 1

Household Contacts

• Evaluate household contacts for evidence of S. aureus infection 1
• Treat symptomatic contacts and consider decolonization following treatment 1
• Consider decolonizing asymptomatic household contacts if ongoing transmission is occurring 2

Monitoring and Follow-up

• Screening cultures prior to decolonization are not routinely recommended if at least one prior infection was documented as MRSA 1
• Surveillance cultures following decolonization are not routinely recommended in the absence of active infection 1
• Monitor for mupirocin resistance, which has been increasing (up to 22.5% in MRSA strains in some settings) 6
• Consider alternative agents such as intranasal povidone-iodine in settings with high mupirocin resistance 6

Efficacy and Outcomes

• Comprehensive decolonization protocols have shown success rates of up to 87-98% when patients complete the full treatment course 4
• Postdischarge decolonization with chlorhexidine and mupirocin leads to a 30% lower risk of MRSA infection compared to education alone 7
• Full adherence to decolonization regimens can reduce MRSA infections by up to 44% 7
• Bundled approaches combining MRSA decolonization with targeted antibiotic prophylaxis have reduced surgical site infections in neurosurgical procedures from 3.0% to 0.8% 5

The most effective approach to MRSA decolonization requires a systematic protocol with attention to all potential colonization sites and appropriate follow-up to ensure successful eradication.