The prevalence of antibodies to HCV and the course of hepatitis have been determined in 357 haemodialysed patients treated at a single institution. The prevalence of HCV infection increases with the duration of haemodialysis and with the use of blood transfusions, yet there is high frequency of HCV seropositivity even without blood transfusions. Evolution of HCV hepatitis to chronicity is frequent and biological signs of chronic hepatopathy can coexist with absence of alanine aminotransferase (ALT) abnormalities.