Objective: To evaluate the specificity of antibodies to hepatitis C virus (anti-HCV) and their relation to liver disease in blood donors.
Design: Case series of consecutive blood donors found positive for anti-HCV by enzyme-linked immunosorbent assay (ELISA). Patients were evaluated for antibody specificity using a recombinant immunoblotting assay (RIBA) and were evaluated for biochemical evidence of liver disease. Patients showing increased alanine aminotransferase (ALT) levels had a liver biopsy.
Setting: University hospital.
Participants: Fifty consecutive blood donors found to be anti-HCV positive on both an initial and repeat ELISA. Inclusion criteria were as follows: an absence of hepatitis B surface antigens and non-organ-specific autoantibodies; a daily alcohol intake of less than 50 g; no history of recent hepatotoxic drug use; and normal serum levels of alpha 1 antitrypsin, ceruloplasmin, and copper.
Main results: Anti-HCV positivity was confirmed by RIBA in only 13 of 50 donors (26%) who had positive ELISA results. These 13 donors had an elevated ALT level and histologic evidence of chronic hepatitis, which was active in 8 patients (62%) and had already produced cirrhosis in 2 patients (15%). In contrast, the 17 donors with an intermediate RIBA pattern had only mild and often nonspecific histologic liver abnormalities. The 20 patients with a negative RIBA result had normal ALT levels.
Conclusion: In blood donors, the anti-HCV RIBA is not only more specific than the anti-HCV ELISA, but is also useful in identifying patients who have an underlying chronic liver disease.