Comparison of real-time polymerase chain reaction using the Smart Cycler and the Gen-Probe amplified Mycobacterium tuberculosis direct test for detection of M. tuberculosis complex in clinical specimens

• Published in: Diagnostic microbiology and infectious disease Vol. 54; no. 3; pp. 217 - 222
• Main Authors: Pounder, June I., Aldous, Wade K., Woods, Gail L.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.03.2006; Elsevier
• Subjects: Bacillus; Bacterial diseases; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Human bacterial diseases; Humans; Infectious diseases; Medical sciences; Microbiology; MTD; Mycobacterium tuberculosis; Mycobacterium tuberculosis - genetics; Mycobacterium tuberculosis - growth & development; Mycobacterium tuberculosis - isolation & purification; Mycobacterium tuberculosis complex; PCR assay; Polymerase Chain Reaction - methods; Predictive Value of Tests; Sensitivity and Specificity; Tuberculosis - diagnosis; Tuberculosis - microbiology; Tuberculosis - physiopathology; Tuberculosis and atypical mycobacterial infections; PCR assay; MTD; Mycobacterium tuberculosis complex; Microbiology; Mycobacterial infection; Real time; Species complex; Infection; Polymerase chain reaction; Tuberculosis; Mycobacterium tuberculosis; Mycobacteriales; Bacteriosis; Mycobacteriaceae; Bacteria; Actinomycetes; Detection; Clinical isolate
• ISSN: 0732-8893; 1879-0070
• DOI: 10.1016/j.diagmicrobio.2005.05.018

The performance of a real-time polymerase chain reaction (PCR) assay using the Smart Cycler instrument and a minor groove binding MGB Eclipse™ probe (Epoch Biosciences, Bothell, WA) for identification of Mycobacterium tuberculosis complex in acid-fast bacillus smear-positive and smear-negative clinical specimens was assessed by comparing results to the Amplified M. tuberculosis Direct Test (MTD) and mycobacterial culture plus clinical diagnosis. After initial testing, the overall sensitivity, specificity, and positive and negative predictive values of PCR for the 172 specimens submitted for mycobacterial culture were 86.3%, 100%, 100%, and 94.5%, respectively. These same values for MTD were 98.0%, 99.2%, 98.0%, and 99.2%. For 83 additional specimens, only MTD and PCR were performed; 5 specimens were positive and 78 were negative by both tests. The sensitivity of the PCR assay was improved by using different primers and probes. The time to a result for real-time PCR, starting with a decontaminated sample, was less than 3 h compared with 5–6 h for the MTD.