阳性血培养中阴性杆菌快速鉴定方法探讨

Evaluation of Rapid Identification of Enterobacteriaaceae in Positive Blood Cultures

目的 结合荧光原位杂交法和直接 VITEK法 ,快速鉴定阳性血培养中的阴性杆菌。方法 当Bac T/ALERT3D1 2 0报警后 ,涂片革兰氏染色 ,若发现阴性杆菌 ,首先与大肠杆菌特异性的探针杂交 ,结果阳性者可直接报告为大肠杆菌 ;结果阴性者 ,将阳性血培养标本中的细菌离心后制成混悬液 ,采用VITEK直接法鉴定。所有菌株同时按标准法分纯后 ,采用 VITEK标准法鉴定 ,比较两法的鉴定结果。结果 分离到的 86株阴性杆菌中 ,在 6h内可鉴定 94%的细菌 ,90 %为正确鉴定。结论 结合荧光原位杂交法和直接 VITEK法 ,可在一天时间内报告鉴定阴性杆菌结果 ,并可将其鉴定至种的水平 。

Objective To develop a new protocol combining Fl uorescent in situs hybridization with direct Vitek test for rapid identification of Gram negative bacili in blood culture.Methods Once mi crocomputer flags positive,made Gram staining of an initial streak-out preparat ion of a positive blood culture.If found Gram stain negative bacili,hybridize wi th E.coli prode.Hybridization positive,reported it as E.coli;hybridizati on negative,performed the direct method using a suspension made by differential centrifugation of positive blood culture broth for inoculation of the Vitek card s,and conducted the standard Vitek cards method using an inoculum made from an o vernight culture on a solid media.Results Of 86 isolates, 94% of identifications were reported within 6h,90% of these were correct.Conclusion The result suggest that this protocol allows rapid id entification for Gram negative bacili in blood cultures and make same-day repor t possible,and can identificate to species level,it is very useful for patients to allow earlier appropriate antimicrobial therapy.