Clonal dissemination of OXA-48-producing Enterobacter cloacae isolates from companion animals in Algeria.

Abstract

The aim of this study was to investigate carbapenemase-producing Enterobacteriaceae (CPE) in companion animals. Between October 2015 and April 2016, 533 rectal swabs were obtained from healthy and diseased pets in different cities in Algeria. Samples were plated on MacConkey agar supplemented with ertapenem (0.5mg/L). Isolates were identified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF/MS). Antimicrobial susceptibility testing was performed by the disk diffusion method. Carbapenemase, plasmid-mediated AmpC (pAmpC), extended-spectrum β-lactamase (ESBL) and plasmid-mediated quinolone resistance genes were characterised by PCR. Plasmids were extracted by the Kieser extraction method and were analysed by PCR-based replicon typing (PBRT). The epidemiological relationship between Enterobacter cloacae isolates was determined by random amplified polymorphic DNA (RAPD) analysis and multilocus sequence typing (MLST). From 533 rectal swabs, 12 Enterobacteriaceae (2.3%), including 2 Escherichia coli, 2 Klebsiella pneumoniae and 8 E. cloacae, were recovered from selection plates. The 12 strains were resistant to amoxicillin/clavulanic acid, ticarcillin, piperacillin/tazobactam and ertapenem. All isolates were susceptible to aminoglycosides, imipenem and extended-spectrum cephalosporins. PCR and sequencing identified the blaOXA-48 gene in all isolates. qnrB1 was identified in all E. cloacae isolates. Plasmid analysis showed that the blaOXA-48 gene was localised on a 7-kb untypeable plasmid. RAPD analysis demonstrated the presence of the same profile pattern in the eight E. cloacae isolates. MLST analysis showed that the E. cloacae isolates belonged to ST527. This study reports for the first time the presence of CPE in horses and pet birds in the world.