BacT/Alert 3D和Bactec^(TM) FX两种血培养系统对真菌血症检出性能的评价

Performance of BacT/Alert 3D and Bactec^(TM) FX in detection of fungemia

目的评价BacT/ALERT 3D与Bactec^(TM) FX两种血培养系统需氧瓶对真菌血症的检出能力。方法用沙堡弱培养基复苏35株实验菌株,用需氧瓶肉汤配制成高低两种浓度的待测瓶,分别放置相对应的全自动血培养仪中同时进行培养;培养瓶阳性报警后,观察生长曲线、记录报警时间,转种沙堡弱培养基培养后重复鉴定,确认与待测菌相同;比较两种血培养系统对真菌血症的检出时间(TTD)。结果血培养系统检出不同菌种的TTD差异有统计学意义(P<0.05),终浓度为3~5CFU/ml的葡萄牙假丝酵母、新型隐球菌、酿酒酵母、不规则毛霉、土曲霉、茄病镰刀菌、层生镰刀菌、马尔尼菲篮状菌和终浓度为30~50CFU/ml的白假丝酵母、近平滑假丝酵母、希木龙假丝酵母、新型隐球菌、酿酒酵母,Bactec^(TM) FX系统检出的TTD均长于BacT/ALERT 3D系统。终浓度为3~5CFU/ml的阿萨希丝孢酵母在Bactec^(TM) FX系统检出的TTD短于BacT/ALERT 3D系统。结论在临床在真菌血症诊断不明确或缺乏真菌瓶的条件下,BacT/ALERT 3D需氧瓶能较快的检出临床常见的真菌血症,对一些机会感染的丝状真菌也有较好的检出效能。

OBJECTIVE To evaluate the performance of the two blood culture systems BacT/ALERT 3 Dand Bactec^（TM） FX in detection of fungemia.METHODS Totally 35 experimental strains were resuscitated on Sabouraud′s Agar and then diluted to the high-concentration test bottle and the low-concentration test bottle with aerobic vial broth,which were placed in the parallel automatic blood culture systems.When the flask alarmed,the growth curve was observed,the alarm time was recorded,they were switched to Sabouraud＇s Agar for repeat identification and smear to confirm.The time to detection（TTD）of fungemia was compared between the types of blood culture systems.RESULTS There was significant difference in the TTD of different species between the two blood culture systems（P〈0.05）.The TTD of Bactec^（TM） FX was longer than that of BacT/ALERT 3 Din the detection of Candida lusitaniae,Cryptococcus neoformans,Saccharomyces cerevisiae,Mucor irregularis,Aspergillus terreus,Fusarium solani,Fusarium proliferatum and Talaromyces marneffei with the final concentration of 3-5 CFU/ml as well as in detection of Candida albicans,Candida parapsilosis,Candida haemulonii,Cryptococcus neoformans and Saccharomyces cerevisiae with the final concentration of 30-50 CFU/ml.The TTD of Bactec^（TM） FX was shorter than that of BacT/ALERT 3 Din detection of Trichosporon asahii with the final concentration 3-5 CFU/ml.CONCLUSION BacT/ALERT 3 Daerobic vials may quickly detect the common clinical fungemia and show good performance in detection of filamentous fungi causing opportunistic infection under the condition of unclear diagnosis of fungemia and absence of fungal vials.