Confirmation of high prevalence of hepatitis C antibodies in hemodialysis patients by second generation immunoblot assay.

Sera from 209 dialysis patients were tested for antibodies to hepatitis C virus (anti-HCV) by a 2nd generation enzyme-linked immunoassay (ELISA 2) using nonstructural and core antigens. Confirmation of reactivity was obtained by a 2nd generation immunoblot assay (RIBA 2) for antibodies to 4 separate antigens (5-1-1, c100-3, c33c, c22-3). ELISA 2 was positive in 99 sera, 95 of which were confirmed by RIBA 2, thus accounting for an anti-HCV prevalence of 45.5%. Anti-HCV positivity was correlated to longer duration of dialysis therapy (p less than 0.001), higher number of transfusions (p less than 0.001), history of kidney transplant (p less than 0.001) and of serum alanine/aspartate aminotransferase (AST/ALT; p less than 0.001) or gamma-glutamyltransferase (GGT) (p less than 0.001) increments. The most frequent RIBA 2 patterns were: reactivity to all 4 antigens (34 patients) and to c33c and c22-3 (45 patients). The former patients, compared to the latter, had higher values of AST (p less than 0.08), ALT (p less than 0.02), GGT (p less than 0.005), IgG (p less than 0.05). It is possible that the reactivity to all 4 antigens of RIBA 2 is a clue of a greater activity of viral hepatic disease.