3种方法鉴定气单胞菌临床分离株效果分析

Comparison of three methods for identification of clinical isolates of Aeromonas

目的比较多位点系统发育分析(MLPA)、质谱仪和生化仪鉴定气单胞菌的效果,为气单胞的种间分型和分类研究提供参考依据。方法收集2014年12月至2017年10月北京友谊医院住院患者及门诊腹泻患者气单胞菌分离株,利用VITEKMS质谱仪、VITEKⅡ全自动细菌鉴定仪和MLPA方法进行鉴定。结果气单胞菌经MLPA分析分为维氏气单胞菌、豚鼠气单胞菌、嗜水气单胞菌、达卡气单胞菌、肠棕气气单胞菌、中间气单胞菌、圣雷利气单胞菌、台湾气单胞菌、双壳类气单胞菌及异嗜糖气单胞菌10种。质谱仪对气单胞属的鉴定率为100.0%,在种型鉴定上,鉴定率为16.2%,对肠棕气单胞菌的正确鉴定率为83.3%(5/6),对中间气单胞菌的正确鉴定率为50.0%(1/2)。生化仪对气单胞属的鉴定率为89.2%,在种型鉴定上,鉴定率为0,均为不确定或错误鉴定。结论 MLPA对气单胞菌属和种型鉴定最准确,而质谱仪在气单胞菌属和种型鉴定上均优于生化仪,质谱仪对少见肠棕气单胞菌及中间气单胞菌有一定分辨能力。

Objective To compare the identification effects of clinical isolates of Aeromonas by using multi locus phylogenetic analysis(MLPA),mass spectrometer(VITEK MS system) and biochemical analyzer(VITEK Ⅱ system) and provide evidence for the research of species identification and classification of Aeromonas.Methods The Aeromonas strains isolated from clinical specimens of hospitalized patients and outpatients suffered from diarrhea in our hospital between December 2014 and October 2017 were collected for the identification with VITEK MS system,VITEK Ⅱ system and MLPA,respectively.Results The isolated Aeromonas strains were divided into 10 species by MLPA,i.e.A.veronii,A.caviae,A.hydrophila,A.dhakensis,A.enteropelogenes,A.media,A.sanarellii,A.taiwanensis,A.bivalvium,and A.allosaccharophila.The identification rate of Aeromonas was 100.0% at genus level and 16.2% at species level by VITEK MS system,in addition,the identification rate was 83.3%(5/6) for A.enteropelogenes and 50.0%(1/2) for A.media.The identification rate of Aeromonas was 89.2% at genus level and 0(unspecified and false) at species level by VITEK Ⅱ system.Conclusion MLPA was an accurate tool for the delineation of Aeromonas species.VITEK MS system was more accurate than VITEK Ⅱ system to identify Aeromonas at both the genus and species level.VITEK MS system had a certain ability to identify rare species of A.enteropelogenes and A.media.