Molecular epidemiology of blaOXA-23-producing carbapenem-resistant Acinetobacter baumannii in a single institution over a 65-month period in north China

BMC Infectious Diseases

Research Article

Jie Huang¹  Nian-zhi Ning¹  Fang-hong Chen¹  Xiong Liu¹  Tao Li¹  Hui Wang¹  Chun-mei Bao²  Fen Qu²  Su-ming Chen²  En-bo Cui²  Ju-ling zhang² 

[1] State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, No.20 Dongda Street, Fengtai District, 100071, Beijing, China;The Center of Clinical Diagnosis Laboratory, Beijing 302 Hospital, 100039, Beijing, China;

关键词: Acinetobacter baumannii;    Carbapenem resistant;    bla;    CC92;    Outbreak;   

DOI  :  10.1186/s12879-016-2110-1

 received in 2016-07-25, accepted in 2016-12-10,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundCarbapenem-resistant Acinetobacter baumannii poses a significant threat to hospitalized patients, as few therapeutic options remain. Thus, we investigated the molecular epidemiology and mechanism of resistance of carbapenem-resistant A.baumannii isolates in Beijing, China.MethodsCarbapenem-resistant A.baumannii isolates (n = 101) obtained between June 2009 and November 2014 were used. Multilocus sequence typing (MLST) and PCR assays for class C and D β-lactamase were performed on all isolates. S1 nuclease pulsed-field gel electrophoresis (PFGE) and Southern blot hybridization were performed to identify the resistance gene location.ResultsAll 101 A.baumannii isolates were highly resistant to frequently used antimicrobials, and were considered multidrug resistant. A total of 12 sequence types (STs) were identified, including 10 reported STs and 2 novel STs. Eighty-seven isolates were classified to clonal complex 92 (CC92), among which ST191 and ST195 were the most common STs. The blaOXA-23 gene was positive in most (n = 95) of the A.baumannii isolates. Using S1-nuclease digestion PFGE and Southern blot hybridization, 3 patterns of plasmids carrying blaOXA-23 were confirmed. ST191 and ST195 (both harboring blaOXA-23) caused outbreaks during the study period, and this is the first report of outbreaks caused by ST191 and ST195 in north China.ConclusionblaOXA-23-producing A.baumannii ST191 and ST 195 isolates can disseminate in a hospital and are potential nosocomial outbreak strains. Surveillance of imipenem-resistant A.baumannii and antimicrobial stewardship should be strengthened.

【 授权许可】

CC BY   
© The Author(s). 2017