Clin-TOF-ⅡMS联合配套预处理试剂盒快速鉴定血培养阳性病原菌的研究

Direct identification of microorganisms from blood culture bottles by Clin-TOF-Ⅱ MS combined with blood culture pretreatment kit

目的使用临床基质辅助激光解析电离飞行时间质谱系统(Clin-TOF-ⅡMS)联合配套预处理试剂盒直接检测血培养阳性报警瓶中的病原菌并评估该方法的鉴定符合率。方法收集大连医科大学附属第一医院2019年1—5月的血培养阳性报警标本254例,在转种培养的同时,抽取报警瓶中的液体并使用血培养预处理试剂盒富集、纯化报警瓶中的菌体,采用Clin-TOF-ⅡMS对待测病原菌进行直接鉴定,并将直接鉴定结果与转种培养后的菌落鉴定结果进行比较。结果254例血培养阳性报警瓶中,237例为单一菌感染标本,17例为混合菌感染标本。与菌落鉴定结果相比,单一菌感染标本中Clin-TOF-ⅡMS直接检测鉴定的符合率为86.5%(205/237),其中革兰阳性菌的符合率为81.0%(94/116),革兰阴性菌的符合率为93.9%(108/115);17例混合菌感染标本鉴定的符合率为17.6%(3/17),有3例未鉴定出结果,其余11例混合菌感染均鉴定出其中一种细菌。结论Clin-TOF-ⅡMS联合配套预处理试剂盒直接检测血培养阳性报警瓶中病原菌,可缩短病原菌的鉴定时间,且与传统菌落鉴定方法比有较高的鉴定符合率,适合在临床微生物实验室推广应用。

Objective To evaluate the consistency rates of identifying the microorganisms directly from positive blood culture bottles by Clin-TOF-ⅡMS combined with blood culture pretreatment kit.Methods A total of 254 positive blood culture bottles were collected from the First Affiliated Hospital of Dalian Medical University during January to May 2019.Positive cultures were sub-cultured on to routing plates,and at the same time,the microorganisms were enriched and purified by blood culture pretreatment kit.Clin-TOF-ⅡMS was applied to identify the microorganisms and the results were compared with conventional bacterial culture.Results The 254 positive culture specimens included 237 of single bacterial infection specimens and 17 multiple bacterial infection specimens.Compared with traditional identification results,the consistency rates of Clin-TOF-ⅡMS combined with blood culture pretreatment kit in single bacterial infection identification were 86.5%(205/237),which of Gram-negative bacteria was 93.9%(108/115)and Gram-positive bacteria was 81.0%(94/116)respectively.And totally 17.6%(3/17)of multiple bacterial infections were identified,3 of 17 multiple bacterial infection specimens were not identified,and the remaining 11 multiple bacterial infection specimens were identified one of the bacteria.Conclusion The identification time of microorganisms in positive blood culture bottles can be shortened by Clin-TOF-ⅡMS combined with blood culture pretreatment kit.Compared with the traditional identification,it has higher consistency rate,and recommended for clinical microbiology laboratories.