A prospective study of liver disease has been conducted among patients entering our Dialysis Unit between 1987 and 1990. On entry, 7 patients had a history of blood transfusions but none had clinical or biochemical features of liver disease. During follow-up, 13 further patients were transfused; 1 case developed acute resolving hepatitis B and another acute non-A, non-B hepatitis progressing to chronicity. Eleven other cases showed transient or fluctuating ALT abnormalities. On entry, anti-HCV was negative by both 1st and 2nd generation ELISA assays (Ortho-Diagnostic Systems) in all cases. During follow-up, a positive reaction was detected in 17 cases: 4 patients were positive by both assays and 13 only by 2nd generation test (p < 0.01). HCV was implicated in 66% of cases with liver disease of the non-A, non-B type and in 50% of transfused as compared to 23% of nontransfused cases (p = n.s.). These findings suggest that HCV could play a major etiological role in liver disease of hemodialysis patients and that anti-C100 reactivity is more affected by immunosuppression associated with chronic uremia.