ABSTRACT
The aim of this study was to test the performance of a new reagent kit Tosoh TRCRapid M.TB using by transcription-reverse transcription concerted reaction(TRC) for detection of Mycobacterium tuberculosis complex (MTC) by comparing both its sensitivity and specificity for detecting MTC with those of Roche COBAS AMPLICOR Mycobacterium assay using polymerase chain reaction (PCR) and comparing with culture. TRC is a novel method, that is rapid and provides real-time monitoring of the isothermal sequence of RNA amplification without any post-amplification procedure, and the resulting detection time was about 30 min. A total of 157 clinical samples from patients were tested. Of the 74 MTC culture-positive samples, TRC was positive in 59(sensitivity, 80%), whereas PCR was positive in 47(sensitivity, 63%). The 26 samples that were positive for Mycobacteria other than tuberculosis (MOTT) were negative by TRCRapid M.TB assay, and the 50 samples that were negative for smear, culture and Roche PCR were also negative by TRCRapid M.TB. The percent agreement between Tosoh TRCRapid M.TB and Roche COBAS AMPLICOR was 90% (142 of 157 samples). These results indicate that Tosoh TRCRapid M.TB may be more useful than Roche COBAS AMPLICOR for detecting MTC because of its higher sensitivity and shorter detection time.
Subject(s)
Bacteriological Techniques , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/isolation & purification , Polymerase Chain Reaction/methods , RNA, Bacterial/analysis , RNA, Ribosomal/analysis , Reagent Kits, Diagnostic , Reverse Transcriptase Polymerase Chain Reaction/methods , Sputum/microbiology , Mycobacterium avium Complex/genetics , Mycobacterium avium Complex/isolation & purification , Sensitivity and SpecificityABSTRACT
Recently, we evaluated the clinical significance of a new assay, the semi-automated Cobas Amplicor HCV Monitor test v 2.0 (Roche, Cobas-HIGH-RANGE assay), for quantifying serum hepatitis C virus RNA throughout a wider range than the traditional assay, Amplicor GT HCV Monitor test v 2.0 (GT-ORIGINAL assay). We compared the results of the Cobas-HIGH-RANGE assay with results of the GT-ORIGINAL assay. This study was conducted on serum from 91 patients with chronic hepatitis C at the Gastroenterological Center, Yokohama City University Medical Center. The percent coefficient of variation (CV) for the within-run and between-run reproducibility of the Cobas-HIGH-RANGE assay ranged from 0.7 to 2.3% and from 1.3 to 2.0%, respectively. The Cobas-HIGH-RANGE assay exhibited a linear range extending from 5 to 5000 KIU/ml. The values for all 17 samples determined as less than 0.5 KIU/ml by the GT-ORIGINAL assay were also determined as less than 5 KIU/ml by the Cobas-HIGH-RANGE assay. For the 48 samples with values of 0.5 to 850 KIU/ml determined by the GT-ORIGINAL assay, the values obtained by these two assay methods were significantly correlated (r2 = 0.9117, y = 1.0667x-0.0801, p < 0.001), but the values of HCV-RNA determined by the Cobas-HIGH-RANGE assay were significantly (p < 0.05) higher than those determined by the GT-ORIGINAL assay. Consequently, these data indicate that the HIGH-RANGE assay is a useful alternative assay method for measurement of HCV-RNA instead of the ORIGINAL assay, and that the HIGH-RANGE assay could be a useful tool for monitoring the efficacy of antiviral treatment.
