Multilocus sequence typing of carbapenem resistant Acinetobacter baumannii from Zhejiang Province / 中华检验医学杂志

Objective To investigate the molecular epidemiology of carbapenem resistant Acinetobacter baumannii from Zhejiang Province using multilocus sequence typing.Methods Three hundred and two imipenem or meropenem resistant A.baumannii isolates were collected from eleven tertiary hospitals of eleven different regions of Zhejiang Province in 2009 and 2010.Multilocus sequence typing was used for molecular typing.eBURST was used to analyze the results of multilocus sequence typing.PCR was used to detect the OXA-type carbapenemase genes.Results Seventeen sequence types (STs) were identified from three hundred and two A.baumannii isolates.eBURST analysis revealed eleven STs belonged to clonal complex 92 (CC92) and corresponded to European clone Ⅱ lineage.CC92 was the predominant carbapenem resistant A.baumannii clone of Zhejiang Province,which accounted for 94.4％ (285/302) of all isolates and distributed in all 11 hospitals.blaOXA-23 gene was identified in 97.4％ (294/302) of all isolates.Conclusions Carbapenem resistant A.baumannii CC92 were clonal disseminated among multiple hospitals of Zhejiang Province.blaOXA-23 was the most popular carbapenemase gene in carbapenem resistant A.baumannii.(Chin J Lab Med,2013,36:303-307)

Investigation on the genotyping of Acinetobacter baumannii by DiversiLab system / 中华检验医学杂志

Objective To evaluate the usefulness of DiversiLab system for genotyping of Acinetobacter baumannii.Methods Fifty-eight non-duplicated clinical Acinetobacter baumannii isolated from 15 cities in China in 2005 were typed by rep-PCR-based DiversiLab system.The results were compared with those of PFGE and multilocus sequence typing. Simpson's index of diversity was used to compare the discriminatory power among DiversiLab system, PFGE and MLST.Results Fifty-eight Acinetobacter baumannii isolates were differentiated into 5 clusters and 25 unique types by DiversiLab system. MLST identified 35 distinct sequence types, which fell into one clone complex of CC22 and 35 singletons, while PFGE resolved 5 pulsotypes and 34 unique types.Simpson's diversity indices for DiversiLab system, MLST and PFGE were O.876, O.944 and 0.961, respectively.Conclusions The discriminatory power of DiversiLab system is lower than that of PFGE and MLST.But as a simple, fast and reproducible typing method, it could be used as a first-line typing tool for the analysis of a large number of isolates.