Prevalence of methicillin resistance in isolates from dogs with skin and ear infections in South Africa.

() is an important opportunistic pathogen, frequently associated with pyoderma and otitis in dogs. The emergence and rapid expansion of methicillin-resistant (MR) is problematic due to multidrug resistance and reduced treatment options. The aim of this study was to determine i) the prevalence of MR in dogs with pyoderma or otitis externa, ii) the antimicrobial resistance patterns of MR from South African isolates, and iii) the risk factors for MR-associated pyoderma or otitis externa in dogs in South Africa (RSA). Sixty-eight presumptive clinical isolates (collected from 65 dogs) from five geographically dispersed laboratories in RSA were collected over 2 years. Possible MR isolates were flagged when resistance to oxacillin was observed. Thereafter, all isolates were confirmed as by polymerase chain reaction (PCR) and further genotyped for the A gene. Fifty-seven of 68 isolates were confirmed to be (83.8%), while 49/57 (85.9%) carried A. Our findings showed that preliminary phenotypic methods supplemented by genotypic methods increased the accuracy of correctly identifying . All isolates were resistant to at least one antimicrobial drug. There was a high incidence of amoxicillin (70.1%) and enrofloxacin (65%) resistance. Important risk factors for A positive carriage were previous hospital admission, pruritus, and previous antibacterial failure. This study demonstrates a high prevalence of A positive carriage (85.9% of samples) in MR pyoderma and otitis in dogs in RSA. There is an urgent need for better laboratory diagnosis of MR and surveillance of dogs presenting with pyoderma and otitis in South Africa.