Περίληψη:
Objectives: The objective of this study was to examine Klebsiella oxytoca clonal and phylogenetic diversity, based on an international collection of carriage isolates non-susceptible to expanded-spectrum cephalosporins (ESCs). Methods: The study material comprised 68 rectal carriage K. oxytoca isolates non-susceptible to ESCs recovered in 2008-11 from patients in 14 hospitals across Europe and Israel. ESC resistance was tested phenotypically; genes encoding ESBLs, AmpC cephalosporinases and carbapenemases were amplified and sequenced. The isolates were typed by PFGE and MLST, followed by sequencing of blaOXY genes. Results: MLSTand PFGE distinguished 34 STs and 47 pulsotypes among the isolates, respectively. Six STswere split into several pulsotypes each. Five STs were more prevalent (n=2-9) and occurred in several countries each, including ST2, ST9 and ST141, which belong to a growing international clonal complex (CC), CC2. Four phylogenetic lineages were distinguished, each with another type of chromosomal OXY-type β-lactamase. Three of these, with OXY-1/-5, OXY-2 types and OXY-4, corresponded to previously described phylogroups KoI, KoII and KoIV, respectively. A single isolate from Israel represented a distinct lineage with a newly defined OXY-7 type. The phylogroups showed interesting differences in mechanisms of ESC resistance; KoI strains rarely overexpressed the OXY enzymes but commonly produced ESBLs, whereas KoII strains often were OXY hyperproducers and carried ESBLs much less frequently. AmpCs (DHA-1) and carbapenemases (VIM-1) occurred sporadically. Conclusions: The study confirmed the high genetic diversity of the collection of K. oxytoca ESC-non-susceptible isolates, composed of phylogroups with distinct types of OXY-type β-lactamases, and revealed some STs of broad geographical distribution.
Συγγραφείς:
Izdebski, R.
Fiett, J.
Urbanowicz, P.
Baraniak, A.
Derde, L.P.G.
Bonten, M.J.M.
Carmeli, Y.
Goossens, H.
Hryniewicz, W.
Brun-Buisson, C.
Brisse, S.
Gniadkowski, M.
Herda, M.
Dautzenberg, M.J.
Adler, A.
Kazma, M.
Navon-Venezia, S.
Malhotra-Kumar, S.
Lammens, C.
Legrand, P.
Chalfine, A.
Giamarellou, H.
Petrikkos, G.L.
Balode, A.
Dumpis, U.
Stammet, P.
Aragăo, I.
Esteves, F.
Torres Martí, A.
Lawrence, C.
Salomon, J.
Paul, M.
Lerman, Y.
Rossini, A.
Salvia, A.
Vidal Samso, J.
Fierro, J.
MOSAR WP2, WP3
WP5 Study Groups
Λέξεις-κλειδιά:
bacterial enzyme; beta lactamase AmpC; carbapenemase; cephalosporin derivative; cephalosporinase; extended spectrum beta lactamase; OXY 1 beta lactamase; OXY 2 beta lactamase; OXY 3 beta lactamase; OXY 4 beta lactamase; OXY 5 beta lactamase; unclassified drug; antiinfective agent; beta lactamase; cephalosporin derivative, antibiotic resistance; Article; bacterial chromosome; bacterial gene; bacterial strain; bacterium isolate; clonal evolution; comparative study; controlled study; enzyme analysis; gene amplification; gene sequence; genetic variability; genotype; human; hydrolysis; Klebsiella oxytoca; major clinical study; nonhuman; nucleotide sequence; phenotype; phylogenetic tree; species diversity; antibiotic resistance; classification; DNA sequence; drug effects; Europe; feces; genetic variation; genetics; genotype; heterozygote; hospital; isolation and purification; Israel; Klebsiella Infections; Klebsiella oxytoca; microbial sensitivity test; microbiology; molecular typing; phylogeny; polymerase chain reaction, Anti-Bacterial Agents; beta-Lactam Resistance; beta-Lactamases; Carrier State; Cephalosporins; Europe; Feces; Genetic Variation; Genotype; Hospitals; Humans; Israel; Klebsiella Infections; Klebsiella oxytoca; Microbial Sensitivity Tests; Molecular Typing; Phylogeny; Polymerase Chain Reaction; Sequence Analysis, DNA
