COMPARATIVE-STUDY OF CONVENTIONAL AND NOVEL STRATEGIES FOR THE DETECTION OF HEPATITIS-C VIRUS-RNA IN SERUM - AMPLICOR, BRANCHED-DNA, NASBA AND IN-HOUSE PCR

The aim of this study was to compare the sensitivity and specificity o f conventional procedures (in-house one-stage polymerase chain reactio n (PCR) and in-house nested PCR) and of new technologies (rTth DNA pol ymerase (Amplicor), branched-DNA, NASBA (nucleic acid amplification sy stem)) for the qualitative detection of hepatitis C virus (HCV) RNA in serum of HCV-infected individuals. Serum samples from 37 anti-HCV-pos itive individuals (15 with a normal alanine aminotransferase (ALT) lev el, 22 with an elevated ALT level) and 10 anti-HCV-negative individual s as negative controls were studied. A second panel, including 9 dilut ed serum samples (from 1/10 to 1/100,000) was constituted to establish the differences of sensitivity of the 5 procedures with small quantit ies of HCV RNA in the serum. The anti-HCV-positive individuals with el evated ALT gave positive results with all 5 procedures. In patients wi th a normal ALT level, the assays with the highest sensitivity were Am plicor, NASBA and nested RT-PCR, followed by one-stage RT-PCR, then br anched-DNA. One false-positive result was observed with Amplicor, and two with in-house nested PCR. On diluted samples, Amplicor, NASBA and nested PCR appeared more sensitive than one-stage PCR and branched-DNA . It is concluded that new procedures have satisfactory sensitivity an d specificity and could advantageously replace the conventional PCR pr ocedures for the routine qualitative detection of serum HCV RNA.