两种不同血培养系统对模拟菌血症标本检测能力的比较

目的 比较BACT/ALERT VIRTUO和BACTEC^TM FX两种血培养系统对模拟菌血症标本的检测能力。 方法 本研究采用模拟的血培养, 选用血流感染常见的3种革兰阴性杆菌、2种革兰阳性球菌、1种专性厌氧菌和两种念珠菌, 9种检测的抗菌药物。比较的系统为BACT/ALERT VIRTUO血培养系统配合FA Plus需氧瓶(FA+)和FN Plus厌氧瓶(FN+), BACTEC^TM FX血培养系统配合含树脂的需氧培养瓶(AF)和含溶血素的厌氧培养瓶(ANF), 检测每种微生物的检出率和阳性检出时间, 并用色谱方法检测FA+、FN+、AF和ANF对万古霉素、美罗培南和氟康唑的吸收率。 结果 在模拟的血培养中, 在有抗菌药物的情况下, 几种培养瓶的阳性检出率为VIRTUO系统的FN+(42/50, 84.00%)>VIRTUO FA+(30/50, 60.00%)>FX AF(20/50, 40.00%), FX ANF溶血素厌氧瓶因为无抗菌药物吸附能力, 检出率为0。FA+、FN+、AF和ANF的阳性检出时间中位数分别是13.96、16.22、20.30 h和>120 h。抗菌药物浓度测试结果表明, VIRTUO FN+厌氧瓶对美罗培南的吸附效果非常显著, 2 min时即可吸附约90%的美罗培南。 结论 两个系统在有抗菌药物存在时, 检出率及阳性检出时间均有差异。对微生物的检出, BACT/ALERT VIRTUO血培养系统要优于BACTEC^TM FX血培养系统。

Comparison of detection performance of two blood culture systems for simu-lated bacteremia specimens

Objective To compare the detection performance of BACT/ALERT VIRTUO and BACTEC^TM FX blood culture systems for simulated bacteremia specimens. Methods This study adopted simulated blood culture, three kinds of Gram-negative bacilli, two kinds of Gram-positive cocci, one kind of obligate anaerobe and two kinds of candida that are frequent in blood stream infection, as well as nine tested antimicrobial agents. The BACT/ALERT VIRTUO blood culture system with FA Plus aerobic vials (FA+) and FN Plus anaerobic vials (FN+), as well as the BACTEC^TM FX blood culture system with resin aerobic culture vials (AF) and hemolysin anaerobic culture vials (ANF) were compared. Detection rate and positive detection time of each microorganism were determined. The absorption rates of FA+, FN+, AF and ANF to vancomycin, meropenem and fluconazole were detected by chromatography. Results In simulated blood culture with the presence of antimicrobial agents, the positive detection rates of culture vials of VIRTUO system were FN+(42/50, 84.00%)>VIRTUO FA+(30/50, 60.00%) >FX AF (20/50, 40.00%). Due to the lack of antimicrobial adsorption ability, the positive detection rates of FX ANF hemolysin anaerobic vials was 0. The median positive detection times for FA+, FN+, AF, and ANF were 13.96, 16.22, 20.30 hours, and >120 hours, respectively. Antimicrobial concentration test results showed that the adsorption effect of meropenem by VIRTUO FN+anaerobic vials was obvious, and about 90% of meropenem could be adsorbed in 2 minutes. Conclusion There are differences in the detection rate and positive detection time between the two systems in the presence of antimicrobial agents. The BACT/ALERT VIRTUO blood culture system is superior to the BACTEC^TM FX blood culture system in detecting microorganisms.