Isolation of Escherichia coli Strains with AcrAB–TolC EffluxPump-Associated Intermediate Interpretation or Resistance to Fluoroquinolone,Chloramphenicol and Aminopenicillin from Dogs Admitted to a University VeterinaryHospital

Journal of Veterinary Medical Science

Risa ICHIHASHI¹  Yutaka TAMURA¹  Toyotaka SATO¹  Nobuhiro FUJII²  Shin-ichi YOKOTA²  Masaru USUI¹  Torahiko OKUBO¹  Tomoka MIYAUCHI¹ 

[1] Laboratory of Food Microbiology and Food Safety, Department of Health and Environmental Sciences, School of Veterinary Medicine, Rakuno Gakuen University, 582 Midorimachi, Bunkyodai, Ebetsu 069�?8501, Hokkaido, Japan;Department of Microbiology, Sapporo Medical University School of Medicine, South-1, West-17, Chuo-ku, Sapporo, Hokkaido 060�?8556, Japan

关键词: AcrAB;    antimicrobial resistance;    canine;    efflux pump;    Escherichia coli;   

DOI  :  10.1292/jvms.13-0144

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

References(29)Understanding the prevalenceof antimicrobial-resistance and the relationship between emergence of resistant bacteriaand clinical treatment can facilitate design of effective treatment strategies. We hereexamined antimicrobial susceptibilities of Escherichia coli isolated fromdogs admitted to a university hospital (University hospital) and companion animal clinics(Community clinics) in the same city and investigated underlying multidrug-resistancemechanisms. The prevalence of E. coli with intermediate and resistantinterpretations to ampicillin (AMP), enrofloxacin (ENR) and chloramphenicol (CHL) washigher in the University hospital than in the Community clinics cases. Use ofantimicrobials, including fluoroquinolone, was also significantly higher in the Universityhospital than in the Community clinics cases. Upon isolation using ENR-supplemented agarplates, all ENR-resistant isolates had 3�?4 nucleotide mutations that accompanied by aminoacid substitutions in the quinolone-resistance-determining regions ofgyrA, parC and parE, and 94.7% of allisolates derived from the University hospital showed AMP and/or CHL resistance andpossessed blaTEM and/or catA1. The averagemRNA expression levels of acrA, acrB andtolC and the prevalence of organic solvent tolerance, in isolatesderived from ENR-supplemented agar plates were significantly higher in the Universityhospital than in the Community clinics isolates. Thus, E. coli derivedfrom the University hospital cases more often showed concomitant decreasedsusceptibilities to aminopenicillins, fluoroquinolones and CHL than did those derived fromthe Community clinics; this was related to an active AcrAB–TolC efflux pump, in additionto acquisition of specific resistance genes and genetic mutations.

【 授权许可】

Unknown