title: Characterization of isolates of Salmonella enterica serovar typhimurium displaying high-level fluoroquinolone resistance in Japan.
abstract: Strains of the multidrug-resistant (MDR) Salmonella enterica serovar Typhimurium isolated in Japan were examined for high-level fluoroquinolone resistance. Since the first isolation in 2000 (described in reference 13), we have identified 12 human and 5 nonhuman isolates with high-level fluoroquinolone-resistance (ciprofloxacin MIC of 24 microg/ml or more). Most of these isolates shared some features including definitive phage type (DT 12/193), resistance type (ACSSuTNCp; resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, tetracycline, nalidixic acid, and ciprofloxacin), and genotype on pulsed-field gel electrophoresis that were different from those of the MDR S. enterica Typhimurium DT 104. Mutations in quinolone resistance-determining regions of gyrA and parC were also conserved in almost all of the isolates despite the absence of any apparent epidemiological relationships among cases. This suggests that a specific clonal group of the serovar Typhimurium with high levels of fluoroquinolone resistance is disseminating among animals and humans in Japan.
authors.affiliation: Department of Bacteriology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan. izumiya@nih.go.jp
authors.forename: Hidemasa
authors.initials: H
authors.lastname: Izumiya
authors.forename: Kadumi
authors.initials: K
authors.lastname: Mori
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kurazono
authors.forename: Masanori
authors.initials: M
authors.lastname: Yamaguchi
authors.forename: Masato
authors.initials: M
authors.lastname: Higashide
authors.forename: Noriko
authors.initials: N
authors.lastname: Konishi
authors.forename: Akemi
authors.initials: A
authors.lastname: Kai
authors.forename: Koji
authors.initials: K
authors.lastname: Morita
authors.forename: Jun
authors.initials: J
authors.lastname: Terajima
authors.forename: Haruo
authors.initials: H
authors.lastname: Watanabe
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D001434:Bacteriophage Typing; D002415:Cats; D004285:Dogs; D024881:Drug Resistance, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D024841:Fluoroquinolones / Q000494:pharmacology*; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D012480:Salmonella Infections / Q000382:microbiology; D012486:Salmonella typhimurium / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D024841:Fluoroquinolones