| Summary: | Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) is an important cause of nosocomial infections in humans, but its importance in small animal practice is increasing. Here, we present a case of feline otitis externa (OE) caused by MRSA; both hemolytic and nonhemolytic variants with a stable phenotype were recovered from the external auditory canal after infection was detected by routine otoscopy. One isolate per variant underwent antimicrobial susceptibility testing (AST) by broth microdilution method, conventional <i>spa</i> typing and whole-genome sequencing (WGS). The results showed that both variants were genetically related and were of sequence type (ST) 1327, SCC<i>mec</i> type IV and <i>spa</i> type t005. AST and WGS showed that both isolates were resistant to β-lactams and sensitive to all tested non-β-lactam antibiotics. Both isolates were <i>pvl</i>-negative, but encoded several other virulence genes (<i>aur</i>, <i>hlgABC</i>, <i>sak</i>, <i>scn</i>, <i>seg</i>, <i>sei</i>, <i>sem</i>, <i>sen</i>, <i>seo</i> and <i>seu</i>). Genetic background of the mixed hemolytic phenotype was not identified; no differences in the <i>agr</i> locus or other regulatory regions were detected. Three single-nucleotide polymorphisms were identified but could not be associated with hemolysis. This well-documented case of MRSA infection in companion animals adds to the reports of MRSA infections with a mixed hemolytic phenotype.
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