Frequency, Distribution, and Antimicrobial Resistance of Coagulase-Negative Staphylococci Isolated from Clinical Samples in Dogs and Cats
Nathita Phumthanakorn, Nuvee Prapasarakul, Jitrapa Yindee, Dulyatad Gronsang
Abstract
This study aimed to investigate the frequency, distribution, and antimicrobial resistance of coagulase-negative staphylococci (CoNS) obtained from clinical samples from dogs and cats and to classify any methicillin-resistant CoNS (MRCoNS). The samples were collected in 2017–2018, and species identification and antimicrobial susceptibility testing were routinely performed using the Vitek2 system. Among 1,056 staphylococci, 185 CoNS (17.5%) were obtained and included 18 species from dogs ( n = 116) and 14 species from cats ( n = 69). The predominant species were Staphylococcus chromogenes (31.4%) , Staphylococcus hominis ssp. hominis (16.2%), Staphylococcus warneri (10.8%), and Staphylococcus epidermidis (8.1%). The primary isolation sites were the skin and urinary tract. High levels of resistance to β-lactams (65.4%), tetracycline (44.3%), clindamycin (36.8%), and erythromycin (30.8%) were observed. Twenty-five MRCoNS (13.4%), mainly Staphylococcus haemolyticus ( n = 8), S. epidermidis ( n = 6), and S. hominis ssp. hominis ( n = 5), were identified. SCC mec type V ( n = 8) was the most common type, followed by SCC mec type IV ( n = 6) and SCC mec type III ( n = 2), whereas nontypable SCC mec were classified into nine MRCoNS. Some CoNS have been recorded in humans, and these might be transferred to and cause subsequent infections in humans. Moreover, the diversity of SCC mec types and resistant strains suggested that they may serve as a reservoir of resistance genes among staphylococci.