[Prevalence of antibodies against hepatitis C virus in rheumatoid arthritis. Study using second-generation tests].

: In order to evaluate the seroprevalence of anti-hepatitis C virus (HCV) antibody in rheumatoid arthritis (RA), where a high prevalence of false-positive anti-HCV reactions is reported, we studied 79 patients affected with RA. In these subjects we recorded some clinical and anamnestic data (history of blood transfusion, risk factors of liver disease, therapy) and determined, besides a few routine laboratory parameters including rheumatoid factor (RF), AST and ALT, the anti-HCV serology using the 1st (EIA, Ortho and Abbott; Neutralization test, Abbott; RIBA, Chiron-Ortho) and the 2nd generation tests (EIA, Ortho; RIBA, Chiron-Ortho). Four patients (of whom three were RF seronegative) were anti-HCV reactive by the 1st generation EIA tests (5.1%). According to the results of the confirmatory tests, and particularly of the 2nd generation, two patients resulted infected by HCV. These results do not confirm the previously reported high prevalence of false-positive anti-HCV reactions in RA, and demonstrated the usefulness of the 2nd generation tests in diagnosing the HCV infection.