What is the recommended treatment approach for a patient requiring MRSA (Methicillin-resistant Staphylococcus aureus) decolonisation?

MRSA Decolonization

For patients requiring MRSA decolonization, use intranasal mupirocin 2% ointment applied to both anterior nares twice daily for 5-10 days combined with daily chlorhexidine gluconate body washes for 5-14 days. 1

When to Decolonize

Decolonization is not routinely recommended for asymptomatic MRSA carriers. 2 Consider decolonization only in these specific scenarios:

• Recurrent skin and soft tissue infections despite optimized wound care and hygiene measures 1, 2
• Ongoing household transmission among close contacts despite hygiene interventions 1, 2
• Pre-operative screening before high-risk surgeries (cardiac, orthopedic, or surgeries involving prosthetic material) 1, 3
• Following treatment of active infection when preventing recurrence is critical 3

The strongest evidence supports pre-operative decolonization before cardiac and orthopedic surgery, where it significantly reduces surgical site infections. 1

Standard Decolonization Protocol

Nasal Decolonization

• Mupirocin 2% ointment applied to both anterior nares twice daily for 5-10 days 1, 2
• This is the gold standard agent with the most extensive evidence base 4, 5

Body Decolonization

Combine nasal mupirocin with one of these options:

• Chlorhexidine gluconate 4% soap for daily full-body washing for 5-14 days 1, 2, 6
• Dilute bleach baths: 1 teaspoon per gallon of water (or ¼ cup per ¼ tub/13 gallons), 15 minutes twice weekly for 3 months 1, 2

The combination approach is more effective than nasal decolonization alone, particularly for recurrent infections. 6, 7

Timing for Surgical Patients

• Complete decolonization 1-2 weeks before surgery 1, 8
• If the 5-day course cannot be completed pre-operatively, finish it post-surgery 1
• Consider postponing elective procedures if decolonization is incomplete and feasible without additional patient risk 1

Essential Concurrent Hygiene Measures

Decolonization fails without these hygiene interventions: 1, 2

• Keep draining wounds covered with clean, dry bandages 1
• Practice hand hygiene with soap and water or alcohol-based sanitizer, especially after touching infected areas 1, 2
• Avoid sharing personal items (razors, towels, linens) that contact skin 1
• Clean high-touch surfaces (counters, doorknobs, bathtubs, toilet seats) with standard commercial cleaners 1
• Wash towels, sheets, and clothing in hot water 2

Household Contact Management

Treating both the patient and household contacts together results in significantly fewer recurrences than treating the patient alone. 2

• Evaluate symptomatic contacts for MRSA infection and treat accordingly 1, 2
• Consider decolonization of asymptomatic household contacts only when ongoing transmission is documented despite hygiene measures 1, 3
• All household members should implement the same hygiene measures 1

Special Populations and Difficult Cases

Pediatric Considerations

• Mupirocin 2% topical ointment can be used for minor skin infections in children 1
• Do not use hexachlorophane in children under 2 months due to neurological complications risk 2
• Tetracyclines should not be used in children <8 years 1

Persistent or Recurrent Colonization

For patients with multiple body sites colonized or treatment failures: 6

• Screen at least 6 body sites (nose, throat, perianal area, rectum, inguinal area, wounds) 6
• Add oral vancomycin for intestinal colonization 6
• Add trimethoprim-sulfamethoxazole for urinary tract colonization 6, 2
• Consider rifampin plus fusidic acid for persistent cases (18% of patients in one study required this) 6
• Treat vaginal colonization with povidone-iodine, chlorhexidine, or octenidine 6

Immunocompromised or Prosthetic Joint Patients

More aggressive and prolonged decolonization protocols may be warranted given higher infection risk. 8

Critical Pitfalls to Avoid

Resistance Development

• High-level mupirocin resistance has been reported with prolonged or indiscriminate use 3, 4
• Do not use mupirocin routinely without confirmed MRSA colonization 4
• Monitor local resistance patterns to mupirocin 1

Recolonization Risk

• Recolonization occurs in 40-60% of patients within 3 months after decolonization 3
• This is temporary clearance, not permanent eradication 2
• Reinforce hygiene measures continuously 1

Screening Cultures

• Do not perform routine screening cultures prior to decolonization if at least one prior infection was documented as MRSA 1, 2
• Do not perform surveillance cultures following decolonization in the absence of active infection 1, 2

Underlying Conditions

Address local factors that perpetuate colonization: 2

• Foreign material
• Hidradenitis suppurativa
• Pilonidal cysts
• Interdigital toe space infections or maceration

Alternative Agents

When mupirocin resistance is documented or suspected:

• Povidone-iodine 5-10% solution shows rapid bactericidal activity against MRSA, including mupirocin-resistant strains 9, 5
• Retapamulin is under investigation for nasal decolonization 4, 5
• Povidone-iodine does not induce bacterial resistance or cross-resistance, unlike mupirocin and chlorhexidine 9

Evidence for Effectiveness

A high-quality 2019 randomized controlled trial demonstrated that postdischarge decolonization with chlorhexidine and mupirocin led to 30% lower risk of MRSA infection compared to education alone (hazard ratio 0.70,95% CI 0.52-0.96), with 85% of prevented infections requiring hospitalization. 7 Patients who fully adhered to the regimen had 44% fewer MRSA infections (hazard ratio 0.56). 7