Severe hepatitis C virus (HCV)-related fibrosing cholestatic hepatitis leading to early liver failure has been reported only exceptionally. Of 259 HCV-infected renal transplant (RT) patients in one hospital unit, four (1.5%) are described, representing the first series of this particular post-RT disease. Patient mean age was 55.7 yr. Three were men. All had pretransplant, hepatitis B surface antigen-negative and were anti-HCV antibodies positive. Three of them showed pretransplant mild liver enzyme abnormalities, and all received kidneys from HCV-negative donors. All were on steroids, cyclosporine, and azathioprine (AZA). The clinical pattern appeared early after RT (mean, 11.5 mo). In three patients, hyperbilirubinemia (6.5 to 20 mg/dl) and high alkaline phosphatase levels (428 to 859 IU/L) were observed. Also, in all subjects, high gamma glutamyl transpeptidase levels (639 to 4270 IU/L), mild aspartate aminotransferase and alanine aminotransferase abnormalities, and serum HCV RNA were observed. Liver biopsy revealed diffuse fibrosis, leukocyte infiltrates, and different degrees of cholestasis, with typical signs of HCV hepatitis in only one patient. Two patients developed subfulminant liver failure and died 2 and 3 mo after biopsy, respectively. One patient also suffered hepatic failure, receiving a liver transplant. The fourth is alive on dialysis awaiting a combined kidney and liver transplant. It is concluded that fibrosing cholestatic hepatitis is a new, early, and severe complication after RT in HCV(+) patients, which appears in patients with ongoing HCV infection under AZA therapy, despite a nonaggressive immunosuppressive protocol. Both HCV and AZA could play a concurrent role in the pathogenesis of this severe complication after RT.