荧光原位杂交法对血培养常见菌的快速鉴定

Rapid Identification of Common Bacteria and Fungus in Blood Culture by Fluorescent In Situ Hybridization

目的 建立快速鉴定阳性血培养的荧光原位杂交法。方法 针对血培养中的常见病原菌 ,以细菌 16SrRNA和真菌 18SrRNA为靶序列 ,设计种属特异性的寡核苷酸探针。BacT/ALERT仪器报警后 ,取阳性血培养液 15 μl于玻片上 ,5 0℃杂交 1h ,然后 5 0℃下洗涤缓冲液洗涤 10min ,荧光显微镜下检测鉴定结果。同时对临床标本进行常规培养鉴定。结果 118份阳性血培养标本中 ,116份标本杂交法检测为阳性 ,敏感率为 98.3%。除少数阴性杆菌 ,阳性杆菌不能鉴定至种属的水平外 ,92 .5 %的病原体可于 2h内鉴定至种或属的水平。结论 荧光原位杂交法可快速鉴定血培养中的常见菌 。

Objective To establish a rapid method for identification of bacteria and fungus in blood cultures by Fluorescent In Situ Hybridization(FISH).Methods Design fluorescence-labeled oligonucleotide probes targeted for 16SrRNA or 18SrRNA to detect common pathogens in blood cultures. Once Bact/Alert gives a flag,withdraw 15 μl blood onto slide,hybridize 1hour at 50℃, wash buffer at 50℃ for 10 minutes, check the slide under epifluorescent microscope,and examine all the specimens by culture method simultaneously to evaluate the clinical value of FISH.Results 116 of 118 positive blood cultures were detected positive by FISH, the sensitivity of FISH is 98.3%. Except a few Gram staining negative rods can not be identified to species level,92.5% pathogens can be identified to genus or species level. Conclusion FISH can identify the common pathogens in blood cultures rapidly, and provide a reliable evidence for early prescription on clinical bacterial and fungus infection.