title: Nosocomial outbreak of genetically related IMP-1 beta-lactamase-producing Klebsiella pneumoniae in a general hospital in Japan.
abstract: Gram-negative bacteria with acquired metallo-beta-lactamase (MBL) resistance are being increasingly described worldwide. Here we report the first case of an outbreak by a cluster of genetically related strains of Klebsiella pneumoniae producing the IMP-1 MBL. Six isolates of K. pneumoniae with a ceftazidime minimum inhibitory concentration >/=64 microg/mL were collected between February 2003 and June 2004 in Hanyu General Hospital, Saitama, Japan. These isolates were analysed to establish the mechanism of resistance. The zone of inhibition of these isolates using ceftazidime or imipenem disks on Mueller-Hinton agar containing dipicolinic acid was much larger than on Mueller-Hinton agar without dipicolinic acid. Polymerase chain reaction and DNA sequencing confirmed that the isolates contained bla(IMP-1) as well as intI1 as a class I integrase gene. Pulsed-field gel electrophoresis was performed, showing that five of the six isolates were related. This outbreak was controlled by restrained and careful use of antibiotics as well as strict hygiene practices.
authors.affiliation: Division of Microbiology, Department of Clinical Laboratory, Hanyu General Hospital, Saitama, Japan.
authors.forename: Shinako
authors.initials: S
authors.lastname: Fukigai
authors.forename: Jimena
authors.initials: J
authors.lastname: Alba
authors.forename: Soichiro
authors.initials: S
authors.lastname: Kimura
authors.forename: Toshie
authors.initials: T
authors.lastname: Iida
authors.forename: Noriko
authors.initials: N
authors.lastname: Nishikura
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Ishii
authors.forename: Keizo
authors.initials: K
authors.lastname: Yamaguchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D003428:Cross Infection / Q000453:epidemiology*; D004269:DNA, Bacterial / Q000235:genetics; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005260:Female; D005798:Genes, Bacterial; D006769:Hospitals, General; D006801:Humans; D019426:Integrases / Q000235:genetics; D007564:Japan / Q000453:epidemiology; D007710:Klebsiella Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D004269:DNA, Bacterial; D019426:Integrases; C409201:beta-lactamase IMP-1; D001618:beta-Lactamases