title: Spread of theblaOXA-23-Containing Tn2008in Carbapenem-ResistantAcinetobacter baumanniiIsolates Grouped in CC92 from China.
abstract: The rapid expansion of carbapenem-resistantAcinetobacter baumannii(CRAB) clinical isolates is a big issue. We investigated the antibiotic susceptibility, molecular epidemiology and resistance gene ofA. baumanniicollected at two hospitals in Shanghai, China. Besides, theA. baumanniiPCR-based replicon typing method (AB-PBRT) was conducted to categorize the plasmids into homogeneous groups on the basis of replicase genes. Most CRAB isolates showed high-level resistance to almost all antibiotics but retain susceptibility to colistin and tigecycline. A total of 101 isolates carriedblaOXA-51-like gene. Sequencing identified the presence ofblaOXA-66for CRAB isolates.blaOXA-23gene were discovered in all CRAB isolates. Each CRAB isolate contained 1-3 of 19 different plasmid replicase (rep) gene homology groups (GRs) and the GR6 (repAci6) was ubiquitous. Genotyping by Multilocus Sequence Typing (MLST) showed seven defined MLST patterns and three novel STs were found. eBURST analysis indicated they were all grouped in CC92 (GCII) with the most frequent ST208 (50%). TwoblaOXA-23-bearing transposons were found: Tn2006and Tn2008. Tn2008were detected in 54 (96.4%) isolates and Tn2006in two remaining isolates. TheblaOXA-23carbapenem gene was vitally associated withrepAci6 plasmid belong to CC92 clonal group. Our survey revealed severe drug resistance inA. baumanniiisolates. Tn2008-containing CC92A. baumanniiwere endemic, which may facilitate theblaoxa23dissemination.
authors.affiliation: Department of Clinical Laboratory, Obstetrics and Gynecology Hospital of Fudan University Shanghai, China.
authors.forename: Yisheng
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Clinical Laboratory, Obstetrics and Gynecology Hospital of Fudan University Shanghai, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.affiliation: Department of Clinical Laboratory, Renji Hospital, Shanghai Jiao Tong University School of Medicine Shanghai, China.
authors.forename: Haomin
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Obstetrics and Gynecology Hospital of Fudan University Shanghai, China.
authors.forename: Chunmei
authors.initials: C
authors.lastname: Ying
keywords: blaOXA–23; carbapenem-resistant Acinetobacter baumannii (CRAB); multilocus sequence type (MLST); plasmid replicase genes; transposon