SINGLE-STEP PCR IN MOLECULAR DIAGNOSIS OF HEPATITIS-C VIRUS-INFECTION

The diagnostic utility of two PCR systems and three PCR detection meth ods for hepatitis C virus (HCV) RNA,vas evaluated in serum samples, A nested PCR was considered the reference assay and was compared with tw o single-step PCR methods: the first is based on the detection of PCR products by liquid hybridization with a P-32-end-labeled probe, and th e second is the Roche Amplicor colorimetric assay using microwell plat e hybridization with a specific nucleic acid probe. Using the Pelichec k HCV RNA Eurohep genotype 1 proficiency panel, our laboratory achieve d medium-high levels of performance with all three methods. The highes t sensitivity was, however, observed with the isotopic single-step PCR (ss-PCR) method. The analytical sensitivity of ss-PCR with isotopic d etection and ss-PCR with colorimetric detection was identical to that of nested PCR, with a 100% result concordance. Comparison of ss-PCR wi th enzyme-linked immunosorbent and RIBA assays in the analysis of clin ical samples showed a high concordance, ss-PCR methods appear more sui table for diagnostic application, Nevertheless, HCV RNA PCR cannot be considered a screening assay; it should be requested in the presence o f reactive serology or specific clinical symptomatology with altered l iver parameters, and it is a potential tool for the follow-up of patie nts with HCV infection.