Methicillin-resistant coagulase-negative Staphylococcus spp. prevalence in Lithuanian dogs: a cross-sectional study

The aim of this study was to investigate the presence and frequency of methicillin-resistant coagulase negative staphylococci in dogs in Lithuania and to characterize them regarding antimicrobial resistance. In 20122013 clinical material was collected from 400 dogs. Three hundred samples from diseased dogs with different clinical conditions (dermatitis, otitis, wound infections, gastrointestinal and respiratory tract infections) as well as 100 samples from pure-breed bitches with reproductive disorders (pyometritis, metritis, partus praematurus), used as breeding animals in kennels, were selected. Twenty MRCNS isolates were obtained from 18 dogs out of 400 tested. All isolates harboured the mecA gene while the niecC (mecLGA251) gene was not found. Ten isolates were detected in vaginal samples of the bitches within 3 large kennels. The prevalence of MRCNS in dogs kept in households was 3.3 % i.e. significantly lower (P<0.01) than in dogs kept in large kennels (10 %). Ten different MRCNS species were detected with the highest prevalence for Staphylococcus haemolyticus. MRCNS isolates were resistant to macrolides (75 %) due to erm(C) and msrA genes, and to tetracycline (65 %) due to tet(K) and/or tet(M) genes. The rate of resistance to gentamicin was 50 % (attributed to aac(6)-Ie-aph(2 '')-Ia, aph(3')-IIIa), and to co-trimoxazole -40 % (dfrG gene). One isolate of S. lentils harboured the dfrK gene. All isolates were susceptible to linezolid, daptomycin and vancomycin. This study revealed that breeding kennels might be a reservoir of MRCNS strains and may pose a risk for the spread of such strains during mating. The focus on the possible spread of multi-resistant S. haemolyticus between companion-animals and humans should be foreseen, as this species plays an important role in human infections as well.