title: Allocation of Klebsiella pneumoniae Bloodstream Isolates into Four Distinct Groups by ompK36 Typing in a Taiwanese University Hospital.
abstract: The OmpK36 porin plays a role in carbapenem resistance and may contribute to bacterial virulence in Klebsiella pneumoniae. This study aimed to investigate the characteristics of different groups of K. pneumoniae separated by ompK36 typing. Among 226 nonduplicate K. pneumoniae bloodstream isolates collected at a Taiwanese hospital in 2011, four ompK36 types, designated types A, B, C, and D, were identified by PCR in 61, 28, 100, and 36 isolates, respectively; 1 isolate was untypeable. Statistical analysis showed significantly higher rates of antimicrobial resistance (all tested antibiotics except meropenem), extended-spectrum β-lactamases or DHA-1 (47.5% together), Qnr-type quinolone resistance determinants (50.8%), and IncFIIA-type plasmids (49.2%) in group A than in others. Seventeen isolates were identified as belonging to 3 international high-risk clones (4 sequence type 11 [ST11], 10 ST15, and 3 ST147 isolates); all isolates but 1 ST15 isolate were classified in group A. The significant characteristics of group C were hypermucoviscosity (62.0%) and a higher virulence gene content. This group included all serotype K1 (n = 30), K2 (n = 25), and K5 (n = 3) isolates, 6 of 7 K57 isolates, all isolates of major clones associated with pyogenic liver abscesses (29 ST23, 11 ST65, 5 ST86, 7 ST373, and 1 ST375 isolates), and 16 (94.1%) of 17 isolates causing bacteremic liver abscesses. Twelve (42.9%) of the group B isolates were responsible for bacteremic biliary tract infections. Group D was predominant (83.3%) among 12 K20 isolates. This study suggests that most clinical K. pneumoniae isolates can be allocated into four groups with distinct characteristics based on ompK36 types.
authors.affiliation: Department of Pathology, College of Medicine, National Cheng Kung University, Tainan, Taiwan Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan jingjou@mail.ncku.edu.tw.
authors.forename: Jing-Jou
authors.initials: JJ
authors.lastname: Yan
authors.affiliation: Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Po-Xing
authors.initials: PX
authors.lastname: Zheng
authors.affiliation: Department of Internal Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.
authors.forename: Ming-Cheng
authors.initials: MC
authors.lastname: Wang
authors.affiliation: Department of Pathology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Shu-Huei
authors.initials: SH
authors.lastname: Tsai
authors.affiliation: Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan Center for Infection Control, National Cheng Kung University Hospital, Tainan, Taiwan.
authors.forename: Li-Rong
authors.initials: LR
authors.lastname: Wang
authors.affiliation: Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Jiunn-Jong
authors.initials: JJ
authors.lastname: Wu
mesh_terms: D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology*; D001426:Bacterial Proteins / Q000235:genetics; D016000:Cluster Analysis; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D005798:Genes, Bacterial; D005838:Genotype; D006785:Hospitals, University; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D017720:Molecular Epidemiology; D058889:Molecular Typing; D010957:Plasmids / Q000032:analysis; D016133:Polymerase Chain Reaction; D018272:Porins / Q000235:genetics; D012189:Retrospective Studies; D013624:Taiwan / Q000453:epidemiology; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; C092233:OmpK36 protein, Klebsiella pneumoniae; D018272:Porins