Department of Laboratory Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, South Korea.
J Clin Microbiol. 2011 Jan;49(1):173-6. doi: 10.1128/JCM.00694-10. Epub 2010 Nov 3.
Nucleic acid-based amplification tests allow the rapid detection of Mycobacterium tuberculosis. Recently, a real-time PCR assay for M. tuberculosis complex, the Cobas TaqMan MTB test (Roche Diagnostics, Basel, Switzerland), was introduced. We performed a prospective study to evaluate the diagnostic performance of the Cobas TaqMan MTB test system. A total of 406 specimens collected from 247 patients were simultaneously tested by conventional culture, Cobas Amplicor MTB PCR, and TaqMan MTB PCR. The cross-reactivity with other Mycobacterium species and the detection limit were also evaluated. Among 406 specimens, a total of 24 specimens (5.9%) were culture positive: 14 specimens were positive by both TaqMan and Amplicor MTB PCRs, while 5 specimens were positive by only TaqMan PCR. The remaining five specimens were negative by both PCR methods. Seven specimens with negative culture results were positive by TaqMan PCR, but five of these were negative by Amplicor MTB PCR. The sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were 79.1%, 98.2%, 73.1%, and 98.7% for TaqMan and 58.3%, 99.5%, 87.5%, and 97.4% for the Amplicor MTB PCR test, respectively. There was no cross-reactivity with M. tuberculosis and nontuberculous mycobacterial species. The detection limit for the Cobas TaqMan MTB PCR test was 4.0 copies/μl. The Cobas TaqMan MTB PCR test showed higher sensitivity for detection of the M. tuberculosis complex without disturbing the specificity and NPV than the Amplicor MTB PCR test.
核酸扩增检测可快速检测结核分枝杆菌。最近，推出了一种结核分枝杆菌复合群实时 PCR 检测法，即 Cobas TaqMan MTB 检测法（罗氏诊断公司，巴塞尔，瑞士）。我们进行了一项前瞻性研究，以评估 Cobas TaqMan MTB 检测系统的诊断性能。共对 247 例患者的 406 份标本同时进行了常规培养、Cobas Amplicor MTB PCR 和 TaqMan MTB PCR 检测。还评估了该检测法与其他分枝杆菌属的交叉反应性和检测下限。在 406 份标本中，共 24 份（5.9%）培养阳性：14 份标本 TaqMan 和 Amplicor MTB PCR 均阳性，5 份标本仅 TaqMan PCR 阳性。其余 5 份标本两种 PCR 方法均为阴性。7 份培养阴性的标本 TaqMan PCR 阳性，但其中 5 份 Amplicor MTB PCR 阴性。TaqMan 的敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）分别为 79.1%、98.2%、73.1%和 98.7%，Amplicor MTB PCR 分别为 58.3%、99.5%、87.5%和 97.4%。该检测法与结核分枝杆菌和非结核分枝杆菌属无交叉反应性。Cobas TaqMan MTB PCR 检测的检测下限为 4.0 拷贝/μl。与 Amplicor MTB PCR 检测相比，Cobas TaqMan MTB PCR 检测对结核分枝杆菌复合体的检测具有更高的敏感性，而特异性和 NPV 不受影响。
