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

MRSA Decolonization

For patients with recurrent MRSA skin and soft tissue infections who have failed hygiene measures, use intranasal mupirocin 2% ointment twice daily for 5-10 days combined with daily chlorhexidine gluconate body washes for 5-14 days. 1, 2

When to Consider Decolonization

Decolonization is not a first-line intervention and should only be pursued in specific circumstances:

• Recurrent MRSA skin infections despite optimized wound care and hygiene measures 1, 2
• Ongoing household transmission among family members or close contacts despite hygiene optimization 1, 2
• Pre-operative screening for patients undergoing elective surgery, particularly those with prosthetic joints, where decolonization should be completed 1-2 weeks before the procedure 3

Do not routinely decolonize asymptomatic MRSA nasal carriers unless one of the above criteria is met 1

Step 1: Optimize Hygiene Measures FIRST (Before Decolonization)

Before attempting decolonization, ensure the following measures are in place:

• Keep all draining wounds covered with clean, dry bandages 2
• Maintain rigorous hand hygiene with soap and water or alcohol-based sanitizer, especially after touching potentially contaminated items 1
• Avoid sharing personal items that contact skin (towels, razors, clothing) 1
• Clean high-touch surfaces regularly with standard household cleaners 1
• Wash towels, sheets, and clothing in hot water 4

Step 2: Decolonization Protocol (If Step 1 Fails)

Standard Regimen

Intranasal mupirocin:

• Apply mupirocin 2% ointment to both anterior nares twice daily for 5-10 days 3, 1, 5
• The 10-dose regimen (twice daily for 5 days) is superior to shorter courses for maintaining decolonization for at least 4 weeks 6

Body decolonization (choose one):

• Chlorhexidine gluconate 4% soap for daily full-body washing during the 5-14 day treatment period 3, 1, 7, OR
• Dilute bleach baths: 1/4-1/2 cup bleach per full bathtub of water, twice weekly for up to 3 months 4, 1

Enhanced Regimen for Difficult Cases

For patients with persistent colonization or treatment failure, consider adding oral antibiotics:

• Rifampin plus doxycycline for 7 days in combination with topical therapy 8
• Oral vancomycin for intestinal colonization 9
• Trimethoprim-sulfamethoxazole as an alternative for difficult-to-eradicate cases 3

The combination of chlorhexidine washes, intranasal mupirocin, oral rifampin, and doxycycline for 7 days achieved 74% decolonization at 3 months and 54% at 8 months in hospitalized patients 8

Household Contact Management

• Symptomatic contacts should be evaluated and treated for possible MRSA infection 1
• Asymptomatic household contacts may be considered for decolonization if there is ongoing transmission within the household 1
• A recent pediatric study found that employing preventive measures for both the patient and household contacts resulted in significantly fewer recurrences than treating the patient alone 4

Important Caveats and Pitfalls

Limited Evidence Base

• The evidence supporting decolonization for community-acquired MRSA is weak, with most studies conducted in healthcare settings or with methicillin-sensitive S. aureus 2
• A randomized trial in military personnel found that intranasal mupirocin alone did not reduce subsequent skin infections 4
• Chlorhexidine-impregnated cloths used thrice weekly after showering were deemed ineffective 4

Mupirocin Resistance

• Test MRSA isolates for mupirocin susceptibility before initiating decolonization, as high-level resistance (MIC ≥512 mcg/mL) occurs with greater frequency in MRSA than methicillin-sensitive strains 5
• Mupirocin-resistant isolates at baseline are associated with a 9.4-fold increased risk of treatment failure 8
• Increased mupirocin use correlates with resistance development; therefore, routine decolonization without confirmed colonization is not prudent 10

When Decolonization Will Not Work

• Local factors such as foreign material, hidradenitis suppurativa, or pilonidal cysts must be addressed, as eradication of these can be curative 4, 2
• Neutrophil dysfunction in patients who develop recurrent abscesses in early childhood 4
• Decolonization may only provide temporary clearance, with recolonization occurring after discontinuation 1

Safety Considerations

• Do not use hexachlorophane in children under 2 months of age due to risk of neurological complications 1

Role of Cultures

• Screening cultures are not routinely recommended in most situations 2
• Consider screening before decolonization if you need to confirm colonization status 1
• Routine surveillance cultures following decolonization are not recommended in the absence of active infection 1

Adjunctive Antibiotic Therapy for Recurrent Abscesses

• For recurrent abscesses specifically, perform incision and drainage and consider a 5-10 day course of an antibiotic active against the pathogen after obtaining cultures 2
• The benefits of adjunctive antimicrobial therapy in preventing recurrences remain uncertain 4, 2