Characterization of plasmid-mediated quinolone resistance determinants in Klebsiella pneumoniae and Escherichia coli from Tokai, Japan

• Published in: Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy Vol. 20; no. 12; pp. 778 - 783
• Main Authors: Okade, Hayato, Nakagawa, Satoshi, Sakagami, Toru, Hisada, Harumi, Nomura, Nobuhiko, Mitsuyama, Junichi, Yamagishi, Yuka, Mikamo, Hiroshige
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.12.2014
• Subjects: Anti-Bacterial Agents - pharmacology; Bactericidal activity; Drug Resistance, Bacterial - genetics; Escherichia coli - drug effects; Escherichia coli - genetics; Escherichia coli Infections - epidemiology; Escherichia coli Infections - microbiology; Hematology, Oncology and Palliative Medicine; Humans; Japan - epidemiology; Klebsiella Infections - epidemiology; Klebsiella Infections - microbiology; Klebsiella pneumoniae; Klebsiella pneumoniae - drug effects; Klebsiella pneumoniae - genetics; Plasmid-mediated quinolone resistance; Plasmids - genetics; Prevalence; qnr; Quinolones - pharmacology; Japan; Plasmid-mediated quinolone resistance; qnr; Klebsiella pneumoniae; Bactericidal activity
• ISSN: 1341-321X; 1437-7780
• DOI: 10.1016/j.jiac.2014.08.018

Abstract The spread of plasmid-mediated quinolone resistance (PMQR) determinants was evaluated in 150 ceftazidime or cefotaxime-resistant clinical isolates of Klebsiella pneumoniae and Escherichia coli from Tokai, Japan between 2008 and 2011. In this study, qnrB , qnrS, and aac(6′)-Ib-cr genes were detected in 12 (50.0%), 4 (16.7%), and 1 (4.2%) of 24 K. pneumoniae isolates, respectively, while qnrA , aac(6′)-Ib-cr , and qepA genes were detected in 1 (0.8%), 11 (8.7%), and 2 (1.6%) of 126 E. coli isolates, respectively. qnr genes were mainly found in K. pneumoniae (66.7%) and to a lesser extent in E. coli (0.8%). We determined the genetic environment of the qnrB4 gene in 24.6 kb class 1 integron structure, including aar-2 , cmlA , blaOXA-10 , aadA1 , qacEdelta1 , sul1 , and blaDHA-1 . In a time-kill assay, introduction of the qnrB4 or qnrS1 plasmid to the recipient E. coli strain decreased the bactericidal activities of fluoroquinolones such as ciprofloxacin, levofloxacin, and pazufloxacin.