RESUMO
BACKGROUND: We comparatively evaluated the performance of the conventional COBAS Amplicor HCV test v2.0 (CAM; Roche Molecular Systems, USA) and the newly developed COBAS AmpliPrep/COBAS TaqMan HCV test v2.0 (CAP/CTM; Roche Molecular Systems) for qualitative detection of hepatitis C virus (HCV) RNA in clinical samples. METHODS: Six hundred serum samples (100 HCV-positive, 500 HCV-negative, as determined by CAM) were selected and analysed using the new qualitative HCV RNA test, CAP/CTM qualitative test. Results were compared by confirmatory CAP/CTM quantitative test, which is a quantitative HCV RNA real-time polymerase chain reaction by Roche Molecular Systems, and anti-HCV test (Roche Diagnostics GmbH, Germany). Twenty-two additional serum samples, which gave a gray zone result by CAM, were selected for comparison. RESULTS: The two qualitative HCV RNA assays yielded concordant results for 586 of 600 tested samples (concordance rate, 97.7%; kappa coefficient, 0.92; 95% confidence interval [CI], 0.87 to 0.96; P<0.001). Upon re-testing by CAM, we found that the concordance rate increased to 98.2% (kappa coefficient, 0.93; 95% CI, 0.89 to 0.97; P<0.001). The additional 22 samples showing gray zone results for CAM were retested and were also tested by CAP/CTM. The results for 13 of these samples changed to negative and were now concordant with the CAP/CTM and confirmatory CAP/CTM quantitative results. For the remaining samples, the results were variable. For all the 22 samples, the results of the new CAP/CTM were in agreement with those obtained by confirmatory CAP/CTM quantitative test. CONCLUSIONS: The results of the two assays were in good agreement, with 97.7% concordance rate. However, CAP/CTM is more sensitive than CAM and showed no gray zone results. Therefore, it can be a more efficient and useful test for the qualitative detection of HCV RNA in clinical samples.
Assuntos
Hepacivirus , Hepatite C , Hepatite , Reação em Cadeia da Polimerase em Tempo Real , RNARESUMO
OBJECTIVE To quantify the HBV DNA in saliva of chronic hepatitis B(CHB) patients and to study its relation to the periodontal status of the patients. METHODS HBV DNA were isolated from 60 patients with CHB by Trizol-chloroform method.HBV DNA levels were tested by real-time PCR technique and their relationship with plaque index,gingival index and probing depth was analyzed. RESULTS The positive rate of HBV DNA was (56.7%,) and the level of HBV DNA was 4.16+0.57(LogE,copies/ml) in saliva.The detectability of HBV DNA in saliva had no significant correlation with the values of oral clinical parameters. CONCLUSIONS The detectability and level of HBV DNA in saliva have no correlation with the oral hygienic parameters.Other sources of the HBV DNA may exist besides the serum in saliva.