In order to evaluate the sensitivity of HCV test, Ortho Second and Third Generation HCV Elisa Tests were used in 315 sera collected from dialysis patients. The agreement between the two tests was 96.5%. RIBA Second and Third generation and PCR were tested in the eleven discordant sera and in specimens collected in 1992 from the same patients and in 20 Ortho-2 and Ortho-3 HCV negative patients. Ortho-3 test is capable of detecting anti-HCV seroconversion earlier than Ortho-2 with increased sensitivity and specificity, as is confirmed by RIBA and PCR tests.