利用质谱技术直接检测阳性血培养瓶中假丝酵母菌属  

Application of matrix-assisted laser desorption ionization time of flight mass spectrometry assay in rapid identification of Candidaspecies cultured positive from blood

作　　者：陈荣[1] 罗燕萍[1] 杨继勇[1] 崔赛[1] 李东冬[1] 王磊利[1] 

机构地区：[1]解放军总医院微生物科,北京100853

出　　处：《中华医院感染学杂志》2014年第14期3629-3631,共3页Chinese Journal of Nosocomiology

基　　金：解放军总医院苗圃基金(12KMM03)

摘　　要：目的研究利用质谱技术直接检测阳性血培养瓶中假丝酵母菌属的试验方法,为假丝酵母菌属所致血流感染提供快速诊断手段。方法将临床分离假丝酵母菌属97株及标准菌株2株,按一定浓度加入血培养瓶中后放入全自动血培养仪孵育模拟临床送检阳性血培养标本,仪器报警阳性后取出培养瓶,采用离心-分离的手工操作方法对标本进行处理,直接上质谱仪进行检测,评价该方法的准确性。结果离心-分离的手工操作方法对标本进行处理后,质谱技术直接检测阳性模拟血培养标本中检测假丝酵母菌属的准确率为91.9%,其中检测白色假丝酵母菌、近平滑假丝酵母菌、克柔假丝酵母菌、热带假丝酵母菌、光滑假丝酵母菌的准确率分别为100.0%、100.0%、92.9%、89.5%、72.2%;菌落计数法测定该方法检测血培养中假丝酵母菌的最低浓度为105 CFU/ml。结论采用离心-分离的手工操作方法可以直接检测阳性血培养瓶中假丝酵母菌属,对于不同的菌种,其检测的准确性差异有统计学意义,该方法简单易操作、准确性较高,可将假丝酵母菌属所致血流感染常规试验室诊断时间缩短24-48h,值得临床实验室推广使用。OBJECTIVE To study the application of matrix-assisted laser desorption ionization time of flight mass spectrometry assay in rapid identification of positive blood-cultured Candidaspecies so as to provide guidance for rapid diagnosis of bloodstream infections caused by the Candidaspecies.METHODS Totally 97clinical isolates of Candidaspecies and 2standard strains were placed in blood culture bottles according to certain concentration and then placed in automatic blood culture system to simulate the positive culture of submitted specimens,the culture bottles were taken out when the instrument alarmed positive,the specimens were processed by using centrifugation-separation manual method,the mass spectrometer was directly applied for the detection,and the accuracy of the method was evaluated.RESULTS After the treatment of centrifugation-separation manual method,the accuracy of mass spectrometry in direct identification of Candidaspecies in positive simulated blood culture specimens was91.9%,the Candidaalbicans 100.0%,Candida parapsilosis 100.0%,Candida krusei 92.9%,Candida tropicalis 89.5%,Candida glabrata 72.2%.The bacterial colony counts method indicated that the minimum concentration of Candida detected by using the method was 105 CFU/ml.CONCLUSION The centrifugation-separation manual method can directly identify the Candidaspecies in the positive blood culture bottles;there is statistically significant difference in the accuracy of identification of different species.The method is simple,and the accuracy is high;it can shorten the time of diagnosis of bloodstream infections caused by the Candida species by 24-48hours and is worthy to be promoted in the clinical laboratory.

关 键 词：血流感染 基质辅助激光解吸电离飞行时间质谱仪 假丝酵母菌属 

分 类 号：R446[医药卫生—诊断学]