Hepatitis C virus infection in anti-HIV positive and negative French homosexual men with chronic hepatitis: comparison of second- and third-generation anti-HCV testing.

ABSTRACT

To determine the prevalence of hepatitis C virus (HCV) infection in homosexuals with chronic hepatitis, we tested for anti-HCV antibodies 113 (47 anti-HIV positive) French non-drug-addicted homosexual men admitted for chronic viral hepatitis. Anti-HCV were detected with second- and third-generation ELISAs (ELISA2 and ELISA3) and RIBAs (RIBA2 and RIBA3). Chronic hepatitis was related to non-A, non-B infection in four, to hepatitis D virus (HDV) infection in five and to hepatitis B virus (HBV) infection in 104 patients. Anti-HCV positivity was found in 50.4% and 12.4% of the 113 patients, with ELISA2 and ELISA3, respectively. Positivity with RIBA2 and RIBA3 was found in only six of the 57 ELISA2 positive patients (all six were ELISA3 positive). The high prevalence of positivity with ELISA2 not confirmed by RIBA2 or RIBA3 suggests false-positive results. ELISA2 positive results were more frequent with frozen serum samples than with fresh serum samples (62% vs 23.5%, p = 0.0003). However, even with fresh serum, ELISA2-positive RIBA-negative results remained frequent in anti-HIV positive patients. ELISA3 seems to give more specific results. We conclude that the prevalence of HCV infection, as assessed with RIBA, was 5.3% among French homosexual men with chronic hepatitis (3.8% after exclusion of transfused patients). This low prevalence suggests that homosexual transmission of HCV is relatively uncommon.