Dissemination of high-level mupirocin-resistant CC22-MRSA-IV in Saxony

Abstract

Mupirocin is used for eradicating methicillin-resistant (MRSA) in nasal colonization. A plasmid-borne gene, , is associated with high-level mupirocin resistance. Despite the fact that, among all MRSA from a tertiary care center in the German state of Saxony, the prevalence of , encoding high-level mupirocin resistance, was approximately 1% over a 15-year period from 2000–2015, a sharp increase to nearly 20% was observed in 2016/2017. DNA microarray profiling revealed that this was due to the dissemination of a variant of CC22-MRSA-IV (“Barnim Epidemic Strain” or “UK-EMRSA-15”), which, in addition to , harbors , , , and – in most isolates – (C). In order to prevent therapy failures and a further spread of this strain, the use of mupirocin should be more stringently controlled as well as guided by susceptibility testing. In addition, MRSA decolonization regimens that rely on other substances, such as betaisodona, polyhexanide or octenidine, should be considered.

Keywords

• methicillin-resistant Staphylococcus aureus
• MRSA
• mupirocin
• high-level mupirocin resistance
• mupA
• “Barnim Epidemic Strain”