title: Clonal dissemination of multilocus sequence type 11 Klebsiella pneumoniae carbapenemase - producing K. pneumoniae in a Chinese teaching hospital.
abstract: Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae has disseminated rapidly in China. We aimed to analyze the molecular epidemiology of four KPC-producing K. pneumoniae strains isolated from a suspected clonal outbreak during a 3-month period and to track the dissemination of KPC-producing K. pneumonia retrospectively. We created antimicrobial susceptibility profiles using an automated broth microdilution system and broth microdilution methods. We screened carbapenemase and KPC phenotypes using the modified Hodge test and meropenem-boronic acid (BA) disk test, respectively. We identified β-lactamase genes with PCR and sequencing. We investigated clonal relatedness for epidemiological comparison using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). All isolates expressed multidrug resistance and yielded positive results for the modified Hodge and meropenem-BA disk tests. The isolates all carried blaKPC -2 , and coproduced CTX-M-type extended-spectrum β-lactamase. PFGE and MLST showed that the isolates were clonally related. The PFGE patterns of these isolates had ≥90% similarity. We found a single clone, sequence type (ST) 11, and its typical dissemination mode resembled clonal spread. The dissemination of KPC-producing K. pneumoniae is clonally related and there is probable local transmission of a successful ST11 clone.
authors.affiliation: Department of Clinical Laboratory, the Ninth People's Hospital, Jiaotong University, Shanghai, China.
authors.forename: Kangde
authors.initials: K
authors.lastname: Sun
authors.forename: Xu
authors.initials: X
authors.lastname: Chen
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Li
authors.forename: Zhongmin
authors.initials: Z
authors.lastname: Yu
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhou
authors.forename: Yuzhong
authors.initials: Y
authors.lastname: Yan
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics*; D015373:Bacterial Typing Techniques; D001483:Base Sequence; D002681:China; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006784:Hospitals, Teaching; D006801:Humans; D007710:Klebsiella Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000635:transmission; D007711:Klebsiella pneumoniae / Q000145:classification* / Q000187:drug effects / Q000201:enzymology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C515384:beta-lactamase CTX-M-2, Klebsiella pneumoniae; D001618:beta-Lactamases; C531581:carbapenemase-2, Klebsiella pneumoniae
keywords: Klebsiella pneumoniae; Klebsiella pneumoniae carbapenemase; multilocus sequence typing; pulsed-field gel electrophoresis