Mupirocin and Chlorhexidine Resistance in Staphylococcus aureus in Patients with Community-Onset Skin and Soft Tissue Infections

Abstract

Decolonization measures, including mupirocin and chlorhexidine, are often prescribed to prevent Staphylococcus aureus skin and soft tissue infections (SSTI). The objective of this study was to determine the prevalence of high-level mupirocin and chlorhexidine resistance in S. aureus strains recovered from patients with SSTI before and after mupirocin and chlorhexidine administration and to determine whether carriage of a mupirocin-or chlorhexidine-resistant strain at baseline precluded S. aureus eradication. We recruited 1,089 patients with community-onset SSTI with or without S. aureus colonization. In addition to routine care, 483 patients were enrolled in a decolonization trial: 408 received intranasal mupirocin (with or without antimicrobial baths), and 258 performed chlorhexidine body washes. Patients were followed for up to 12 months with repeat colonization cultures. All S. aureus isolates were tested for high-level mupirocin and chlorhexidine resistance. At baseline, 23/1,089 (2.1%) patients carried a mupirocin-resistant S. aureus strain and 10/1,089 (0.9%) patients carried chlorhexidine-resistant S. aureus. Of 4 patients prescribed mupirocin, who carried a mupirocin-resistant S. aureus strain at baseline, 100% remained colonized at 1 month compared to 44% of the 324 patients without mupirocin resistance at baseline (P ‫؍‬ 0.041). Of 2 patients prescribed chlorhexidine, who carried a chlorhexidine-resistant S. aureus strain at baseline, 50% remained colonized at 1 month compared to 48% of the 209 patients without chlorhexidine resistance at baseline (P ‫؍‬ 1.0). The overall prevalence of mupirocin and chlorhexidine resistance is low in S. aureus isolates recovered from outpatients, but eradication efforts were less successful in patients carrying a mupirocin-resistant S. aureus strain at baseline.

Emergence of Staphylococcus epidermidis Clinical Isolates with Resistance to Both Mupirocin and Fusidic Acid

“…Mupirocin resistance may be helpful in the spread of multidrug resistance through co-selection with other resistance genes. Previous reports found that mupirocin-resistant S. aureus isolates were multi-resistant to other antimicrobial agents, such as ciprofloxacin, clindamycin, and tetracycline (21,22). Similarly, in present study, mupirocinresistant S. epidermidis were also multi-drug resistant to other antimicrobial agents.…”

Chlorhexidine Bathing in a Tertiary Care Neonatal Intensive Care Unit: Impact on Central Line–Associated Bloodstream Infections

“…Finally, repeated use of CHG for bathing has not been associated with increasing minimum inhibitory concentrations or development of resistance in exposed bacterial strains. 33 " 36 Our study has some limitations. First, because CHG bathing was part of a clinical care protocol, we cannot speculate on compliance to guidelines; we therefore analyzed our data using an intent-to-treat analysis.…”

Targeted Versus Universal Decolonization to Prevent ICU Infection

“…8,[32][33][34][35] MRSA resistance to chlorhexidine lacks a standard definition, but recent reports suggest that resistant strains are rare in the United States. 36,37 A gene encoding a multidrug efflux pump that is active against chlorhexidine has been reported in MRSA, 38 but its clinical significance is not understood. Reduced susceptibility to chlorhexidine has also been reported in gram-negative bacteria.…”