Characterization of Extended-Spectrum-β-Lactamases Produced by Escherichia coli Strains Isolated from Dogs in Poland.

Escherichia coli is a common cause of infections in companion animals. In recent years the increasing prevalence of resistance to β-lactams, including extended-spectrum cephalosporins, antimicrobials frequently used in small animal veterinary practice, was observed in canine isolates of E. coli. The aim of this study was to detect and to characterize extended-spectrum β-lactamases (ESBLs) produced by E. coli isolated from diseased dogs in Poland. Four isolates out of 119 studied (3.4%) were ESBL-positive. They harbored the bla(SHV-12), bla(CTX-M-15), and bla(TEM-116) genes. This study provides the first report of the occurrence of ESBL-producing E. coli in dogs in Poland.