title: Evaluation of the Cobas TaqMan MTB real-time PCR assay for direct detection of Mycobacterium tuberculosis in respiratory specimens.
abstract: The Cobas TaqMan MTB assay is a real-time PCR (qPCR) kit for rapid detection of Mycobacterium tuberculosis from clinical specimens. There are, however, limited studies validating its performance. We performed a prospective study in two hospitals in Taiwan on 586 respiratory specimens. By using culture as the reference method, the sensitivity and specificity of the Cobas TaqMan MTB assay were found to be 82.7 and 96.5 %, respectively. The sensitivity of the Cobas TaqMan MTB assay in acid-fast stain-negative respiratory specimens was only 34.9 %. Five specimens from five patients were positive for M. tuberculosis by the Cobas TaqMan MTB assay but were negative for M. tuberculosis by conventional culture methods. A diagnosis of pulmonary tuberculosis (TB) was made based on clinical and radiological findings as well as the response to anti-TB treatment in these five patients. Addition of data from these five specimens with discrepant results (PCR vs culture) from patients with symptoms clinically compatible with TB increased the sensitivity of the Cobas TaqMan MTB assay to 83.1 %. The Cobas TaqMan MTB assay is a rapid identification tool with a high degree of specificity for the direct detection of M. tuberculosis in respiratory specimens. The sensitivity for detecting acid-fast smear-negative respiratory specimens, however, is low.
authors: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC.|Department of Internal Medicine, Taoyuan General Hospital, Taoyuan County, Taiwan, ROC.
authors: Meng-Rui
authors: MR
authors: Lee
authors: Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan, ROC.|Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC.
authors: Kuei-Pin
authors: KP
authors: Chung
authors: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC.
authors: Hao-Chien
authors: HC
authors: Wang
authors: Department of Internal Medicine, Buddhist Tzu Chi General Hospital, Hualien, Taiwan, ROC.
authors: Chih-Bin
authors: CB
authors: Lin
authors: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC.
authors: Chong-Jen
authors: CJ
authors: Yu
authors: Department of Internal Medicine, Buddhist Tzu Chi General Hospital, Hualien, Taiwan, ROC.
authors: Jen-Jyh
authors: JJ
authors: Lee
authors: Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan, ROC.|Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC.
authors: Po-Ren
authors: PR
authors: Hsueh
mesh_terms: D006801:Humans; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000302:isolation & purification*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011933:Reagent Kits, Diagnostic; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods* / Q000592:standards; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology*; D013624:Taiwan; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology
chemical_list: D011933:Reagent Kits, Diagnostic