Vitek 2 Compact系统鉴定临床少见疑难细菌的应用及评价

Application and evaluation of Vitek 2 Compact system to identify clinical rare bacteria

目的回顾分析室间质评1304号菌株的鉴定过程,评价Vitek 2 Compact全自动微生物分析系统(简称Vitek 2 Compact系统)在临床少见疑难细菌鉴定中的应用。方法采用传统的细菌形态学检查、手工生化反应及Vitek 2 Compact系统等多种手段对1304号菌株进行鉴定分析,同时用基质辅助激光解吸-电离飞行时间质谱(MALDI-TOF MS)仪对最终鉴定结果进行佐证。结果 1304号菌株为革兰阴性小杆菌,氧化酶试验阳性,初次上机鉴定结果为支气管炎鲍特菌,鉴定率99%,转种分纯后2次上机鉴定结果为低分辨,粪产碱杆菌占51%,类产碱假单胞菌占49%,补充硝酸盐还原试验,结果为阴性,报告最终鉴定结果为粪产碱杆菌,质谱鉴定得分值为2.158,与最终结果相符。结论 Vitek 2 Compact系统鉴定临床少见疑难细菌有一定局限性,遇到少见疑难细菌应该用多种方法加以确定,综合分析以免造成错误鉴定。

Objective To retrospectively analyze the identification process of strain 1 304 in external quality assessment,and to evaluate the application of Vitek 2 Compact automatic microorganism analyzer system （Vitek 2 Compact system）to identify clinical rare bacteria.Methods Strain 1 304 was identified comprehensively by traditional microscopic morphology,manual biochemical reaction and Vitek 2 Compact system,simultaneously.The final result was confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDI-TOF MS）.Results Strain 1 304 was Gram-negative bacilli.The result of oxidase test was positive.The first result was Bordetella bronchiseptica （identification probability was 99%）.The second result was low discrimination（51 % Alcaligenes faecalis and 49% Pseudomonas pseudoalcaligenes）by Vitek 2 Compact system.The result of supplementary test（NO3 ）was negative.The final identification result was Alcaligenes faecalis,and MALDI-TOF MS got the same result with a score value of 2.1 58.Conclusions It exists some limitations in the identification of rare bacteria by Vitek 2 Compact system.Comprehend means should be used to decrease wrong identification rate.