Characterisation of Extended β-Lactamases and Plasmid Mediated Quinolones Resistancein Escherichia Coli from Shelter Dogs

Abstract

The aim of this study was to determine the prevalence of β-lactamase (TEM, SHV, OXA), extended-spectrum β-lactamase (ESBL) and genes encoding plasmid mediated resistance to quinolones (PMQR) in extended spectrum cephalosporin (ESC)-resistant Escherichia coli isolated from dog faeces from two shelters in the North-East of Romania. Eighty-eight faecal samples from healthy dogs were analysed by cultivation on Brilliance ESBL medium (Oxoid, UK), followed by phenotipic ESBL screening using combination disc test (CDT). Identification of the E. coli strains was performed by uidA/uspA gene PCR. Susceptibility testing was performed on Mueller-Hinton Agar, with β-lactam and non-β-lactam agents. Identification of β-lactamase genes (blaCTX-M, blaTEM, blaSHV, blaOXA) and PMQR genes (qnrA, qnrB and qnrS) was performed by PCR as previously described. Twenty eight ESC-resistant E. coli (31.81%) were obtained and (n=21/28, 75%) of these were confirmed as ESBLs and showed resistance to cefpodoxime (n=21/28, 75%), amoxicillin/clavulanic acid (n=19/21; 90.48%), and enrofloxacin (n=8/21; 38.09%). Predominant ESBL types were CTX-M-1 (n=15/17, 88.24%) and CTX-M-9 (n=2/17, 11.76%) enzymes. TEM and SHV enzymes were identified in 17.86% and 14.29% of the ESC-resistant isolates, whilst some isolates (n=4) carried only blaTEM and blaSHV. The prevalence of PMQR genes was 28.57% of the 28 ESC resistant isolates, consisting of qnrS (62.5%) and qnrB (37.5%). These findings indicate a high prevalence of ESBLs and PMQR associated resistance E. coli in the normal faecal microbiota of dogs from shelters, which carries the risk for dissemination of these resistance genes to other animals, human or the environment.

Genomic characterization of ESBL/AmpC-producing and high-risk clonal lineages of Escherichia coli and Klebsiella pneumoniae in imported dogs with shelter and stray background

“…The estimated global prevalence of ESBL-producing E. coli in dogs is 6.29% [2] , and earlier studies from Brazil, Romania, and Japan have shown considerably higher proportions of ESBLproducing Enterobacteriaceae in sheltered and stray dogs, ranging from 14.6 to 31.0% [3][4][5] . Moreover, a recent project by the Finnish Food Authority revealed that the proportion of ESBL-producing En- terobacteriaceae was 30% amongst imported dogs, many of which had a stray or shelter background [6] .…”