MALDI-TOF MS技术在快速鉴定革兰阴性杆菌血流感染中的应用

Application of MALDI-TOF MS technology in rapid identification of Gram negative bacilli induced bloodstream infection

目的探讨VITEK MS质谱仪基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)在快速鉴定革兰阴性(G^(-))杆菌血流感染中的应用。方法收集昌吉回族自治州人民医院2020年1月—2021年12月检测的血培养阳性瓶,经涂片染色确认为单一G^(-)杆菌的163份标本,采用分离胶促凝管短时培养法,在规定时间(1 h、2 h、4 h、6 h)内使用VITEK MS质谱仪MALDI-TOF MS技术进行快速鉴定,并采用传统转种培养VITEK 2 Compact全自动细菌鉴定及药敏分析系统验证鉴定结果。结果与传统转种培养法结果比较,除4份未给出鉴定结果外,其余159份样本经MALDI-TOF MS技术鉴定结果均相符,在规定时间(1 h、2 h、4 h、6 h)内成功鉴定率分别为78.6%(125/159)、85.5%(136/159)、96.2%(153/159)、100.0%(159/159)。结论采用MALDI-TOF MS技术结合分离胶促凝管短时培养法,对病原菌的鉴定时间可由原来的1~2 d缩短至1~6 h,该方法对血培养阳性G^(-)菌的鉴定符合率高,操作方法简单,有较好的临床应用价值。

Objective To explore the application of VITEK MS mass spectrometer matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF MS)in rapid identification of Gram negative(G^(-))bacilli induced bloodstream infection.Methods The 163 blood culture positive bottles and specimens smear stained as single G^(-)bacilli were collected from January 2020 to December 2021 in Changji Hui Autonomous Prefecture People's Hospital.Using the short-time culture method of separating gel promoting tube,the rapid identification was carried out by VITEK MS mass spectrometer MALDI-TOF MS technology at the specified time points of 1 hour,2 hours,4 hours and 6 hours,and the identification results were verified by traditional seed transfer culture using VITEK 2 Compact automatic bacterial identification and drug sensitivity analysis system.Results Compared with the results of traditional seed transfer culture method,the identification results of 159 cases by MALDI-TOF MS technology were consistent except 4 cases.The successful identification rates at 1 hour,2 hours,4 hours and 6 hours were 78.6%(125/159),85.5%(136/159),96.2%(153/159)and 100.0%(159/159),respectively.Conclusions The application of MALDI-TOF MS technology combined with short-time culture method of separating gel promoting tube could shorten the identification time from 1-2 days to 1-6 hours.This method has high coincidence rate for the identification of blood culture positive G^(-)bacteria,simple operation method and good clinical application value.