title: Genetic Characterization of ST195 and ST365 Carbapenem-Resistant Acinetobacter baumannii Harboring blaOXA-23 in Guangzhou, China.
abstract: We investigated the distribution of resistance genes and the clonal relationships among carbapenem-resistant Acinetobacter baumannii isolates from the intensive care unit wards of two hospitals in Guangzhou, China. From 2012 to 2013, 57 A. baumannii isolates were obtained from blood cultures from two hospitals in Guangzhou. The antibiotic resistance profiles were determined by using the Vitek2 system and Etest strips. PCR was used to detect the genes encoding OXA-type carbapenemases and metallo-β-lactamases and the presence of ISAba1 upstream of the bla(OXA-51-like) gene and the bla(OXA-23-like) gene. Multilocus sequence typing (MLST) and sequence-based typing of bla(OXA-51-like) genes (SBT-bla(OXA-51-like )genes) were performed to analyze the genetic relationship of the isolates. Among the 57 isolates, 46 were carbapenem-resistant A. baumannii (CRAB) isolates. The bla(OXA-51-like) gene was identified in all 57 isolates, while the bla(OXA-23-like) gene was present in all 46 CRAB isolates. The MLST analysis grouped the A. baumannii isolates into five existing sequence types (STs) and five new STs. Fifty-two isolates belonged to the worldwide spread of clonal complex 92 (CC92), among which ST195 and ST365 were the most common STs. The MLST data and SBT-bla(OXA-51-like) genes showed that all isolates harboring the major bla(OXA-51-like) alleles, such as bla(OXA-66), belonged to CC92.
authors.affiliation: 1 Guangzhou Center for Disease Control and Prevention , Guangzhou, China .
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: 1 Guangzhou Center for Disease Control and Prevention , Guangzhou, China .
authors.forename: Xinwei
authors.initials: X
authors.lastname: Wu
authors.affiliation: 1 Guangzhou Center for Disease Control and Prevention , Guangzhou, China .
authors.forename: Xinqiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: 1 Guangzhou Center for Disease Control and Prevention , Guangzhou, China .
authors.forename: Yushan
authors.initials: Y
authors.lastname: Hu
authors.affiliation: 2 Department of Biochemistry, Zhongshan Medical School, Sun Yat-sen University , Guangzhou, China .
authors.forename: Xia
authors.initials: X
authors.lastname: Yang
authors.affiliation: 1 Guangzhou Center for Disease Control and Prevention , Guangzhou, China .
authors.forename: Zhicong
authors.initials: Z
authors.lastname: Yang
authors.affiliation: 1 Guangzhou Center for Disease Control and Prevention , Guangzhou, China .
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
mesh_terms: D000151:Acinetobacter Infections; D040981:Acinetobacter baumannii / Q000235:genetics*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D015780:Carbapenems / Q000494:pharmacology*; D002681:China; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics; D006761:Hospitals; D006801:Humans; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D001618:beta-Lactamases; C000599728:beta-lactamase OXA-23, Acinetobacter baumannii; C063912:carbapenemase