title: Spread and genetic characterization of ST137 and ST138 multidrug-resistant Acinetobacter baumannii isolated from a tertiary hospital in Korea.
abstract: Acinetobacter baumannii is an increasingly important global nosocomial pathogen. Clonal complex 92 (CC92) has become the most prevalent clonal complex in many regions. We investigated the molecular epidemiology and resistance profile of 52 imipenem-nonsusceptible A. baumannii isolates obtained from a university hospital in Daejeon, Korea, from 2007 to 2011. The minimum inhibitory concentrations of 7 antimicrobials were determined. PCR and DNA sequencing were used to identify genes contributing to resistance phenotypes. Multilocus sequence typing was performed to determine epidemiological relationships, and European clonal lineages were identified by multiplex PCR. The A. baumannii isolates were of 6 sequence types (STs; ST92, ST75, ST137, ST138, ST358, and ST69) and 1 allelic profile. All 6 STs were clustered into CC92 and the European clone II. ST138 was the most commonly observed ST, followed by ST137. We identified several genetic characteristics in carbapenem-, aminoglycoside-, and fluoroquinolone-resistance genes between ST137 and ST138. Imipenem-nonsusceptible A. baumannii has emerged in Daejeon, Korea, over a 5-year period, and is associated with the global spread of CC92 and European clone II. Epidemiological surveillance may be required to track the spread of epidemic strains and to guide adequate containment measures.
authors.affiliation: Department of Laboratory Medicine, College of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Hye Hyun
authors.initials: HH
authors.lastname: Cho
authors.forename: Kye Chul
authors.initials: KC
authors.lastname: Kwon
authors.forename: Ji Youn
authors.initials: JY
authors.lastname: Sung
authors.forename: Sun Hoe
authors.initials: SH
authors.lastname: Koo
mesh_terms: D000151:Acinetobacter Infections / Q000453:epidemiology*; D040981:Acinetobacter baumannii / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D000890:Anti-Infective Agents / Q000494:pharmacology; D016000:Cluster Analysis; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology*; D018432:Drug Resistance, Multiple / Q000235:genetics*; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D060885:Multiplex Polymerase Chain Reaction; D056910:Republic of Korea / Q000453:epidemiology; D013045:Species Specificity
chemical_list: D000890:Anti-Infective Agents
keywords: CC92; European clone II; Imipenem-nonsusceptible A. baumannii