A retrospective analysis of antimicrobial resistance in bacterial pathogens in an equine hospital (2012–2015)

Abstract

Antimicrobial resistance has become an important concern in veterinary medicine. The aim of this study was to describe the rate of antimicrobial resistance in common equine pathogens and to determine the occurrence of multidrug-resistant isolates. A retrospective analysis of all susceptibility testing results from bacterial pathogens cultured from horses at the University of Zurich Equine Hospital (2012-2015) was performed. Strains exhibiting resistance to 3 or more antimicrobial categories were defined as multidrug-resistant. Susceptibility results from 303 bacterial pathogens were analyzed, most commonly Escherichia coli (60/303, 20%) and Staphylococcus aureus (40/303, 13%). High rates of acquired resistance against commonly used antimicrobials were found in most of the frequently isolated equine pathogens. The highest rate of multidrug resistance was found in isolates of Acinetobacter baumannii (23/24, 96%), followed by Enterobacter cloacae complex (24/28, 86%) and Escherichia coli (48/60, 80%). Overall, 60% of Escherichia coli isolates were phenotypically ESBL-producing and 68% of Staphylococcus spp. were phenotypically methicillin-resistant. High rates of acquired antimicrobial resistance towards commonly used antibiotics are concerning and underline the importance of individual bacteriological and anti microbial susceptibility testing to guide antimicrobial therapy. Minimizing and optimizing antimicrobial therapy in horses is needed. Keywords: horse, multidrug-resistant (MDR) bacteria, methicillin-resistant staphylococci (MRS), ESBL-producing

Infections caused by multidrug‐resistant bacteria in an equine hospital (2012–2015)

“…; van Spijk et al . ). Pan‐resistant A. baumannii strains are a serious problem in human medicine and MDR A. baumannii have already been isolated from horses (Jokisalo et al .…”

“…; van Spijk et al . ). This definition was applicable to Enterobacteriaceae, S. aureus , A. baumannii , Enterococcus spp.…”

“…), but a high rate of multidrug resistance was recently shown in these pathogens isolated from infections in horses (van Spijk et al . ).…”

“…Less is known about the role of other MDR isolates such as Acinetobacter baumannii, Enterococcus spp. and Pseudomonas aeruginosa in equine infections (Jokisalo et al 2010;Herdan et al 2012;Theelen et al 2014), but a high rate of multidrug resistance was recently shown in these pathogens isolated from infections in horses (van Spijk et al 2016b).…”

“…The aim of this study was to report cases with diagnosed infections caused by MDR bacteria in horses at the Equine Hospital of the University of Zurich between 2012 and 2015, in order to provide an overview of their occurrence, clinical presentation and outcome. more defined antimicrobial categories and adapted from the definition in human medicine (Magiorakos et al 2012;van Spijk et al 2016b). This definition was applicable to Enterobacteriaceae, S. aureus, A. baumannii, Enterococcus spp.…”