PNA-FISH技术鉴定血培养中白色假丝酵母菌的方法研究

Preliminary exploration of PNA-FISH for identification of Candida albicans in blood cultures

目的采用PNA-FISH技术进行快速、准确的鉴定血培养中白色假丝酵母菌的方法学初索。方法模拟血培养阳性标本的制备;对所有血培养报阳的标本均进行革兰染色,初步区分报阳菌的种类;对于镜下显示为念珠菌的标本用两种方法对其进行鉴定,一种为PNA-FISH技术,另一种为传统的科马嘉念珠菌显色培养基鉴定技术,最后对这两种方法检测白色假丝酵母菌的特异度、敏感度及检测时间做对比分析。结果 PNA-FISH方法鉴定血培养中白色假丝酵母菌的特异度为100.0%,敏感度为97.5%;采用PNA-FISH技术鉴定血培养中白色假丝酵母菌的时间为（4±0.2）h,较传统真菌鉴定时间（18~24）h明显缩短。结论采用PNA-FISH技术鉴定血培养中白色假丝酵母菌特异性强,敏感度高,所需时间短,值得临床推广。

OBJECTIVE To evaluate the diagnostic performance of PNA-FISH to rapidly and accurately identify Candida albicans of positive blood cultures.METHODS Blood culture positive specimens were simulated,and gram staining was used,and the type of pathogen was preliminarily identified.Two methods were used to identify the specimens which were displayed as Candida by microscopy,including PNA-FISH and traditional Chromagar Candida chromogenic medium identification technology.The specificity,sensitivity and detection time of the two methods were compared.RESULTS The specificity and sensitivity of PNA-FISH method for identification of C.albicans were 100%and 97.5%,and the detection time was（4±0.2）h,which was significantly shorter than（18~24）h of traditional method.CONCLUSIONPNA-FISH is specific and sensitive for the identification of C.albicans of positive blood cultures,it needs shorter time,and is worthy of clinical promotion.