Horvath Lynn L, George Benjamin J, Murray Clinton K, Harrison Linda S, Hospenthal Duane R
Department of Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas 78234, USA.
J Clin Microbiol. 2004 Jan;42(1):115-8. doi: 10.1128/JCM.42.1.115-118.2004.
A direct comparison of two automated blood culture systems was conducted to compare their ability to detect Candida growth. The systems evaluated were the BACTEC 9240 (Bactec) and BacT/ALERT 3D (BacT). The aerobic, anaerobic, and mycology media for each system were evaluated: Bactec Plus Aerobic/F, Plus Anaerobic/F, and Myco/F Lytic bottles, respectively, and BacT FA, SN, and MB bottles, respectively. Each blood culture bottle was inoculated with fresh blood from healthy donors. Fifty isolates of Candida spp. were used. The six different blood culture bottles were each inoculated with 1000 yeasts per bottle and then incubated in the corresponding automated system. The BacT detected growth of 90% (135 of 150) of Candida pathogens, while Bactec detected 66% (100 of 150). Growth was detected in all BacT and Bactec mycology bottles, all BacT aerobic bottles, and by terminal subculture of all bottles. Sixty-five of 300 (22%) bottles had no growth detected; 50 from the Bactec (5 aerobic and 45 anaerobic) and 15 from the BacT (all anaerobic). Terminal subculture of "negative" bottles demonstrated viable yeast growth from all 65 bottles, representing 65 false-negatives. The mean time to growth detection in the BacT system was 25.62 h while the Bactec was 27.30 h (P < 0.01). Both automated blood culture systems detected all episodes of simulated candidemia when specialized mycology media were used. However, when only standard aerobic and anaerobic media were used, the BacT performed better than the Bactec in overall growth detection, time to growth detection, and number of false-negatives.
对两种自动化血培养系统进行了直接比较，以比较它们检测念珠菌生长的能力。所评估的系统为BACTEC 9240（Bactec）和BacT/ALERT 3D（BacT）。对每个系统的需氧、厌氧和真菌学培养基进行了评估：分别为Bactec Plus需氧/F、Plus厌氧/F和Myco/F Lytic瓶，以及BacT FA、SN和MB瓶。每个血培养瓶接种来自健康供体的新鲜血液。使用了50株念珠菌属分离株。六个不同的血培养瓶每个接种1000个酵母细胞，然后在相应的自动化系统中孵育。BacT检测到90%（150株中的135株）念珠菌病原体生长，而Bactec检测到66%（150株中的100株）。在所有BacT和Bactec真菌学瓶、所有BacT需氧瓶以及所有瓶的终末传代培养中均检测到生长。300个瓶中有65个（22%）未检测到生长；50个来自Bactec（5个需氧和45个厌氧），15个来自BacT（均为厌氧）。“阴性”瓶的终末传代培养显示所有65个瓶均有活酵母生长，代表65例假阴性。BacT系统中生长检测的平均时间为25.62小时，而Bactec为27.30小时（P<0.01）。当使用专门的真菌学培养基时，两种自动化血培养系统均检测到所有模拟念珠菌血症病例。然而，当仅使用标准需氧和厌氧培养基时，BacT在总体生长检测、生长检测时间和假阴性数量方面表现优于Bactec。
