Antibody testing and RT-PCR results in hepatitis C virus (HCV) infection: HCV-RNA detection in PBMC of plasma viremia-negative HCV-seropositive persons.

To evaluate the concordance between viremia and antibody testing in hepatitis C virus (HCV) diagnosis, 682 serum or plasma samples collected from patients with known or suspected HCV infection were tested. An overall concordance of 77% between serological and PCR results was found, 5% was RNA positive/antibody negative and 18% antibody positive/RNA negative. The relationship between HCV infection, risk group and clinical diagnosis was studied in 116 patients: the presence of anti-HCV antibody without viremia was shown in 72.7% of asymptomatic subjects and 17.6% of chronic hepatitis subjects without interferon treatment. However, the detection of HCV-RNA in peripheral blood mononuclear cells (PBMC) in four out of 38 plasma viremia-negative HCV-seropositive subjects (10.5%), showed that HCV-RNA could persist in PBMC and could begin the viral replication again at different times. The detection of HCV-RNA in PBMC in anti-HCV-positive subjects without viremia could reduce false-negative results of HCV-RNA testing by RT-PCR in serum or plasma.