Rabbit as a reservoir of multidrug-resistant Acinetobacter baumannii expressing the Ade multidrug efflux pumps

Abstract

Acinetobacter baumannii has emerged as a nosocomial pathogen and considered as a major cause of hospital acquired
infections. While A. baumannii in humans have been extensively studied in various situations, the study of A. baumannii
in companion animals is still limited. The aim of this study was to examine the presence and antimicrobial resistance
profile of A. baumannii isolates from companion rabbits. A total of 17 nasal swab from rabbit carcasses were obtained.
A. baumannii was detected in 23.53% (4/17) of the samples and all the isolates exhibited resistance to chloramphenicol,
erythromycin, spectinomycin and trimethoprim. Fifty percent of the isolates (2/4) were multidrug resistance (MDR) A.
baumannii (ABR601 and ABR604) and produced all the Ade multidrug efflux tested including AdeABC, AdeFGH and
AdeIJK. The other 2 isolates, including ABR602 and ABR603, demonstrated different expression profile of the Ade
systems i.e. AdeIJK and AdeFGH-AdeIJK, respectively. Of all the isolates, ABR604 and ABR601 were resistant to 12
and 10 out of the 15 antimicrobials tested, respectively. This study indicates the presence of MDR A. baumannii in pets
other than dogs and cats and highlights the possible role of these animals as reserviors for the spread of MDR A.
baumannii to humans, animals and environment.