title: Rapidly spreading CTX-M-type beta-lactamase-producing Proteus mirabilis in Japan.
abstract: In recent years, increased isolation of extended-spectrum beta-lactamase (ESBL)-producing Proteus mirabilis has been reported in Japan. We undertook an investigation to determine the prevalence of ESBL-producing P. mirabilis isolated in Japan and to characterise the genotype. Seventy-four P. mirabilis isolates recovered from specimens at 54 hospitals in Japan between March and October 2006 were included in the study. Of the 74 P. mirabilis isolates examined, 28 (37.8%) were ESBL-producers. The bla(CTX-M-2) gene was found in 27 isolates, whilst 1 isolate possessed bla(CTX-M-3). Amongst the 28 ESBL-producers, 25 (89.3%) were non-susceptible to ciprofloxacin, whilst 11 (23.9%) of 46 ESBL-non-producing isolates were non-susceptible to ciprofloxacin. Pulsed-field gel electrophoresis (PFGE) analysis of the 28 ESBL-producing isolates from 19 hospitals revealed 17 clusters. The same PFGE type was observed in two or more hospitals especially in the greater Tokyo area, suggesting possible clonal spread and the need for monitoring to determine whether emergence of a dominant clone occurs. Our results show that in Japan there is a high prevalence of CTX-M-type beta-lactamase-producing P. mirabilis. Moreover, these isolates are characterised by reduced susceptibility to fluoroquinolones.
authors.affiliation: Department of Infection Control and Prevention, Faculty of Medicine, Toho University, 4-16-20, Omori-nishi, Ota-ku, Tokyo 143-0015, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Kanayama
authors.forename: Takako
authors.initials: T
authors.lastname: Iyoda
authors.forename: Kaoru
authors.initials: K
authors.lastname: Matsuzaki
authors.forename: Takeshi
authors.initials: T
authors.lastname: Saika
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Ikeda
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Ishii
authors.forename: Keizo
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Intetsu
authors.initials: I
authors.lastname: Kobayashi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques; D002939:Ciprofloxacin / Q000494:pharmacology; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011512:Proteus Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission*; D011513:Proteus mirabilis / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics*; D015363:Quinolones / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D013997:Time Factors; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D015363:Quinolones; D047090:beta-Lactams; D002939:Ciprofloxacin; D001618:beta-Lactamases