title: Molecular characterization of the bla(KPC-2) gene in clinical isolates of carbapenem-resistant  Klebsiella pneumoniae  from the pediatric wards of a Chinese hospital.
abstract: The present study was conducted to confirm the presence of  Klebsiella pneumoniae  carbapenemase (KPC)-producing K. pneumoniae associated with a nosocomial outbreak in a Chinese pediatric hospital. From July 2009 to January 2011, 124 nonduplicated K. pneumoniae isolates were collected from specimens from patients of pediatric units in the hospital. Twelve of the 124 isolates possessed the bla(KPC-2) gene and showed 7 different pulsed-field gel electrophoresis (PFGE) patterns. Meanwhile, 16S rRNA methylase, acc(6')-Ib-cr, and several types of β-lactamases were also produced by the majority of the KPC-producing isolates. Class 1 integron-encoded intI1 integrase gene was subsequently found in all strains, and amplification, sequencing, and comparison of DNA between 5' conserved segment and 3' conserved segment region showed the presence of several known antibiotic resistance gene cassettes of various sizes. The conjugation and plasmid-curing experiments indicated some KPC-2-encoding genes were transmissible. In addition, conjugal cotransfer of multidrug-resistant phenotypes with KPC-positive phenotypes was observed in KPC-producing strains. Restriction endonuclease analysis and DNA hybridization with a KPC-specific probe showed that the bla(KPC-2) gene was carried by plasmid DNA from K. pneumoniae of PFGE pattern B. The overall results indicate that the emergence and outbreak of KPC-producing K. pneumoniae in our pediatric wards occurred in conjunction with plasmids coharboring 16S rRNA methylase and extended-spectrum β-lactamases.
authors.affiliation: The First Affiliated Hospital of Nanchang University, Nanchang University, Yong wai zheng jie No. 17, Nanchang, 330006, People's Republic of China. ly13767160474@sina.com
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiang-Yang
authors.initials: XY
authors.lastname: Li
authors.forename: La-Gen
authors.initials: LG
authors.lastname: Wan
authors.forename: Wei-Yan
authors.initials: WY
authors.lastname: Jiang
authors.forename: Fang-Qu
authors.initials: FQ
authors.lastname: Li
authors.forename: Jing-Hong
authors.initials: JH
authors.lastname: Yang
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D015780:Carbapenems / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D002681:China; D003428:Cross Infection / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D022761:Gene Transfer, Horizontal; D005798:Genes, Bacterial / Q000235:genetics*; D005838:Genotype; D006776:Hospitals, Pediatric; D006801:Humans; D007223:Infant; D007710:Klebsiella Infections / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D008297:Male; D008780:Methyltransferases / Q000235:genetics; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase; D001618:beta-Lactamases; C531581:carbapenemase-2, Klebsiella pneumoniae