基质辅助激光解析电离飞行时间质谱技术早期筛查耐万古霉素屎肠球菌  

Detection of vancomycin-resistant enterococcus faecium by MALDI-TOF MS

作　　者：吴薇[1] 王利君[2] 隋文君[1] 张桂[1] 

机构地区：[1]首都医科大学附属北京同仁医院检验科,北京100730 [2]清华大学附属北京清华长庚医院检验科,北京102218

出　　处：《首都医科大学学报》2015年第3期444-448,共5页Journal of Capital Medical University

基　　金：首都卫生发展科研专项项目(首发2014-4-2055)~~

摘　　要：目的探讨基质辅助激光解析电离飞行时间质谱(matrix-assisted laser desorption ionization-time of flight mass spectrometry,MALDI-TOF MS)快速筛查耐万古霉素屎肠球菌(vancomycin resistant enterococcus faecium,VRE)。方法收集2009至2012年临床分离的150株屎肠球菌为研究对象。其中实验组为60株万古霉素耐药屎肠球菌,对照组为90株万古霉素敏感屎肠球菌(vancomycin susceptible enterococcusfaecium,VSE)。通过PCR方法对所有菌株进行万古霉素耐药基因检测。应用MALDITOF MS检测2组菌株,随机选取实验组30株VRE和对照组30株VSE的质谱峰,应用ClinPro Tools软件统计分析两组之间差异质谱峰的受试者工作特征(receiver operating characteristic,ROC)曲线。用筛选的差异质谱峰来鉴别余下的实验组30株VRE及对照组60株VSE。结果 MALDI-TOF MS鉴定所有菌株均为屎肠球菌,60株VRE均携带vanA基因,90株VSE不携带任何万古霉素耐药基因,两组菌株之间存在2个差异蛋白质谱峰,相对分子质量分别为3 516.14和3 644.12,其曲线下面积(area under curve,AUC)分别为0.782、0.767。同时采用这2个质谱峰时,MALDI-TOF MS检测VRE的敏感度为80%,特异度为90%,假阳性率为10%,假阴性率为10%,阳性预测值为80%,阴性预测值为90%。结论 MALDI-TOF MS能够在药敏结果报告前,菌株鉴定同时快速筛查VRE,据此建立新型报告流程即时指导临床合理使用抗生素。Objective To evaluate a rapid matrix-assisted laser desorption ionization-time of flight mass spectrometry（MAIDI-TOF MS） assay in identifying vancomycin-resistant Enterococcus faecium.Methods Totally 150 enterococcus faecium clinical strains collected from 2009 to 2012 were studied,including 60 vancomycin-resistant enterococcus faecium（VRE） isolates and 90 vancomycin-susceptible（VSE） strains.Resistance genes were detected by gene sequencing.Spectra of 30 VRE and 30 VSE which were randomly chosen,were analyzed by ClinPro Tools program of MALDI-TOF MS in order to screen the discrepancy mass peaks according to ROC curve.30 VRE and60 VSE were detected by MALDI-TOF MS according to the discrepancy mass peaks.Results All strains were verified as enterococcus faecium by MALDI-TOF MS.60 VRE strains carried vanA gene,and 90 VSE strains carried no vancomycin resistant gene.Two discrepancy mass peaks between the two groups of strains were 3516.14,3644.12,of which AUC were 0.782,0.767,respectively.Through the two discrepancy mass peaks,performance of VRE detection method by MALDI-TOF MS were below.Sensitivity =80%,specificity =90%,false positive rate = 10%,false negative rate = 10%,positive predictive value = 80%,negative predictive value = 90%.Conclusion MALDITOF MS can be used accurately to identify VRE,and guide the clinical rational use of antibiotics.

关 键 词：屎肠球菌 万古霉素 质谱 耐药 

分 类 号：R446.1[医药卫生—诊断学]