Hepatitis C virus (HCV) viremia in patients with indeterminate second-generation HCV recombinant immunoblot assay

Positivity of recombinant immunoblot assay (RIBA 2)for detection of antibodies to Hepatitis C virus (anti-HCV) is usually associated with HCV viremia. The significance of an indeterminate RIBA result defined by reactivity to only one HC V antigen is more problematic. The aim of this study was to determine: 1) the prevalence of RIBA indeterminate subjects, and 2) the correlation between RIBA indeterminate result and viremia according to the presence of normal or increased alanine aminotransferase (ALT) levels. In all RIBA 2 indeterminate subjects HCV RNA was detected by reverse transcription polymerase chain reaction (RT-PCR), and serum ALT was measured. An indeterminate RIBA 2 was found in 30 (15.15%) (of subjects. Comparing the distribution of individual reactivity to HCV antigens (c22-3, c33c, c100-3 and 5-1-1) we found the reactivity to c22-3 to be the most frequent (p < 0.001): Of 30 RIBA indeterminate subjects HCV RNA ivas detected in 19 (63,3%) of which 15 (78,9%) were anti-c22-3-positive. Analysing of RNA positivity according to ALT levels, we found that all the patients with elevated ALT and 15.3% of those,? with normal ALT levels were HCV RNA positive. We have found a significant correlation between viremia and elevated ALT levels. This study demonstrated that HCV viremia was frequent in subjects with indeterminate RIBA, especially in those with increased ALT levels.