Chlorhexidine and mupirocin susceptibilities in methicillin-resistant Staphylococcus aureus isolates from bacteraemia and nasal colonisation

Tolerance of MRSA ST239-TW to chlorhexidine-based decolonization: Evidence for keratinocyte invasion as a mechanism of biocide evasion

“…chlorhexidine) seems to be reasonable, but remains controversial. 15,16,20,21,45 In contrast with previous findings, showing a two-to four-fold increase in chlorhexidine MBC of five tested qacA + ST239-TW skin isolates, 13 no conclusion could be drawn from our ST239-TW BSI isolates, since all strains…”

“…The widespread use of biocides for decolonization has become an important infection control intervention to decrease transmission of nosocomial pathogens, but has also raised concerns about the development of bacterial biocide tolerance. 13,16,44,45 Here we show evidence that bacterial uptake into skin cells together with extracellular adherence can protect some MRSA clones against biocide action. This provides a putative mechanism whereby ST239-TW was able to resist chlorhexidine when introduced on the ICU of GSTT, in the absence of a measurable difference in MIC.…”

Susceptibility to chlorhexidine and mupirocin among methicillin-resistant Staphylococcus aureus clinical isolates from a teaching hospital

“…Although the low rate of MUP-and CHX-resistant isolates found in our hospital, we observed that the resistance to MUP raised from 0.67% (1/148) to 4.4% (3/68) in 10 years, in our MRSA isolates. These rates are still low in comparison with the study by Munoz-Gallego et al 22 , who described a resistance to MUP around 15% in blood and nasal isolates, in samples collected between 2012/2014, in Madrid, Spain. In contrast, Brazilian data 23 reported low rates (1.1%) of MUP-resistant MRSA, in children with atopic dermatitis in Porto Alegre, Brazil, similar to our findings, and a higher rate described by Moura et al 24 who presented a MUP-resistant MRSA rate of 72% in samples from nurses' saliva.…”

Molecular Characterization of Nasal Methicillin-Resistant Staphylococcus aureus Isolates Showing Increasing Prevalence of Mupirocin Resistance and Associated Multidrug Resistance following Attempted Decolonization

“…As S. aureus infection is often endogenous (10,11), our study suggests that antimicrobial and antiseptic resistance gene profiles of the original colonizing isolate may inform stewardship and guide systemic prophylaxis and/or antimicrobial therapy. While MDR/mupirocin resistance association has been reported in isolates causing infection (including bloodstream infection) (12)(13)(14), our investigation revealed several MDR genes in addition to ileS2 and/or qacA among MR-MRSA colonizing isolates. Furthermore, cocarriage of antimicrobial/ antiseptic resistance genes was more frequent among isolates from patients with persistent colonization (data not presented here).…”