Research Communications of the 24th ECVIM-CA Congress

Based on these findings, AMC and TMS would be the firstchoice antimicrobial agents for empiric treatment of bacterial The increasing rates of resistance exhibited by uropathogens represent a serious problem for the selection of an appropriate antibiotic. The aim of this study was to determine secular trends of companion animal urinary tract infection (UTI) that involve extended-spectrum b-lactamase (ESBL)-and carbapemenase-producing Gram negative bacteria (namely, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Acinetobacter baumannii), methicillin-resistant-staphylococci (MRS) and ampicillin and high-level-gentamicin-resistance (HLGR) enterococci. Nine hundred and twenty two uropathogenic bacteria were isolated from dogs and cats, between January 1999 and March 2014, at the Veterinary Teaching Hospital of the Faculty of Veterinary Medicine and at veterinary private practices in the Lisbon area. Isolates were identified using standard commercial systems. Susceptibility testing was performed using the disk diffusion and broth microdilution methods. CLSI breakpoints were applied. Extended-spectrum b-lactamases (ESBL) production was screened by double-disk synergy test. The ESBL, plasmid-mediated AmpC, carbapemenases, mecA and aac(6')-Ieaph(2'')-Ia genes were detected by PCR and gene enzymes were sequenced. Among Enterobacteriaceae 0.7% were DHAproducers, 2.7% were ESBL-producers and 3.6% were CMYproducers. All isolates were also multidrug-resistant. Cefalosporinases-producer Enterobacteriaceae were detected in 2000, the first being a CMY-2-producer E. coli. All the ESBL-producers were E. coli or K. pneumoniae producing CTX-M-group 1 enzymes. Ampicillin-resistance in enterococci was present throughout the years (15,4%, n = 8). HLGR appeared in enterococci in 2003 and was confirmed by the detection of the bifunctional enzyme that confers high level resistance to aminoglycosides (7 out of 8 isolates). In this study we showed that in the last decade the emergence of resistance to critically important antimicrobials among uropathogens from companion animals is a concerning fact. The multidrug-resistant Enterobacteriaceae may compromise effective therapeutic options, namely third and fourth generation cephalosporins, fluoroquinolones, trimethoprim/sulpha combinations. The emergence of MRSA/MRSP and HLGR among uropathogens is also a therapeutic challenge. The detection of uropathogens with antimicrobial resistance is not only an animal health issue but also a matter of public health, since companion animals may act as reservoirs of antimicrobial resistant bacteria or resistance genes for humans.