目的:探讨利用分离胶真空采血管离心法和基质辅助激光解析电离飞行时间质谱(MALDI-TOF MS)直接鉴定血培养阳性标本的可能性。方法收集2015年7~12月非重复血培养阳性标本共计216例,将阳性血培养瓶中肉汤用分离胶真空采血管离心富集细菌,反复洗涤2次后高速离心沉淀细菌,采用MALDI-TOF MS 对沉淀的细菌进行鉴定,同时按照传统方法将阳性标本传种、涂片,待次日对菌落进行鉴定。对比分离胶真空采血管离心后直接鉴定与经培养菌落的鉴定结果。结果216例血培养阳性标本均为单一菌种血流感染,经涂片革兰染色其中革兰阳性菌89例、革兰阴性菌119例、真菌8例,经分离胶真空采血管离心后直接鉴定到种190例,其中革兰阳性菌67例、革兰阴性菌111例、厌氧菌4例、真菌8例,与传统培养方法相比符合率为87.9%,其中革兰阳性菌符合率78.8%,革兰阴性菌符合率93.2%,厌氧菌符合率100.0%,真菌符合率100.0%。结论利用分离胶真空采血管的方法可以在短时间内(<30 min)分离富集细菌,进一步经 MALDI-TOF MS 鉴定使得血培养阳性标本的鉴定时间大大缩短,有利于临床血流感染的快速诊断、治疗。
Objective To study the possibility of direct identification of pathogens from positive blood cul-tures by methods of separation gel tube -centrifugation.Methods 216 cases of positive blood culture were collected from 2015.7 to 2015.12.The bacterias were purified from blood culture bottle by separation gel tube.After washing 2 times,identified by MALDI -TOF MS.At the same time,traditional culture,smears and identification were done. Compared the results of identification by two methods.Results 216 cases of positive blood culture were single bacte-rial infection.By Gram stain,89 strains were Gram positive,119 strains were Gram negative and 8 strains were fungal spores.190 cases of positive blood culture were identified by MALDI -TOF MS,it concluded 67 Gram positive strains,111 Gram negative strains,4 anaerobe strains and 8 fungus.Compared with traditional culture,the coincidence rate reached up to 87.9%,Gram positive strains 78.8%,Gram negative strains 93.2%,anaerobe strains 100.0%and fungus 100.0%.Conclusion It takes less than 30 minutes purified from blood culture bottle by separation gel tube.And the time of identification is shorter than traditional culture.This method is good for clinical diagnosis and treatment.