Review article: hepatitis C virus and calcineurin inhibition after renal transplantation.

The impact of hepatitis C virus on patient and graft survival after renal transplantation remains controversial. However, recent studies have given emphasis on the detrimental role of hepatitis C on long-term patient and graft survival after renal transplantation. Various mechanisms can promote the lower survival in hepatitis C virus-positive recipients, i.e. post-transplant diabetes mellitus, liver disease and infections. Novel evidence has been accumulated showing the inhibitory activity of ciclosporin on the hepatitis C virus replication rate in human hepatocytes; ciclosporin has been shown in vitro to suppress hepatitis C virus replication as effectively as interferon alpha. This effect has not been seen with tacrolimus and is separate from its immunosuppressive activity. Data from patients with normal kidney function or after bone marrow transplantation show that ciclosporin inhibits hepatitis C virus replication. It appears that the progression of liver fibrosis is slower in hepatitis C virus-positive liver transplant recipients treated with ciclosporin than tacrolimus. In contrast, the clinical outcome of hepatitis C in hepatitis C virus-positive patients after liver transplantation treated with ciclosporin vs. tacrolimus has given mixed results. No information after renal transplantation is available. Various parameters can promote the worsening of hepatitis C after renal transplantation but choice of calcineurin inhibition is one of the few risk factors that can potentially be modified by the physician. Prospective, comparative trials of ciclosporin and tacrolimus with large size and adequate follow-up after renal transplantation are in progress.