Hepatitis C virus infection in liver allografts.

HCV infection occurs de novo in 10 percent of liver transplant recipients, reflecting transmission of the virus by the donor organ or blood transfusions. A much more common scenario, however, is recurrent allograft infection following liver transplantation for HCV-associated end-stage liver disease. Removal of the native liver in this clinical setting does not lead to eradication of infection. The virus persists in the blood and subsequently replicates under immunosuppression, resulting in a positive PCR test for HCV in most patients following transplantation. Clinically significant hepatitis develops in 44 percent of patients at the University of Pittsburgh, but the reported incidence worldwide varies from 32 to 100 percent. Most patients show mild to moderately active disease, but in our experience, approximately 10 percent of patients develop progressive liver damage evolving into cirrhosis. The 3-year graft survival at Pittsburgh after a mean follow up period of 20 +/- 14 months is 68 percent, which compares with 82 percent graft survival for patients transplanted for diseases other than HCV. The long-term consequences of allograft HCV infection are not yet completely defined, but HCV-associated cirrhosis remains a valid indication for liver transplantation.