OBJECTIVETo investigate the pathological characteristics of HCV infection after liver transplantation.

METHODSThis is a retrospective analysis of the clinico-pathological changes of 73 liver biopsies obtained from 61 patients who had HCV infection (including HCV recurrence and reinfection) after liver transplantation in our center from September 2000 to September 2006.

RESULTSAbnormal enzyme test results due to HCV infection happened on the 9th to the 1553rd post-transplantation surgery day. The serum HCV RNA level was higher than 10(5) copies/ml in 19 cases and between 10(2)-10(5) copies/ml in the other 42 cases. The histological changes in the transplanted livers were hepatocellular degeneration, necrosis and apoptosis, portal infiltrations and fibrosis. They were classified into two stages (early stage and late stage) according to the onset of fibrosis which appeared within 90 days or later after their transplantation in our study. The incidence of predominant portal infiltrates and liver fibrosis in early stage and late stage was 5.7% (2/35) and 94.7% (36/38) (chi2=54.34, P<0.01) and 2.9% (1/35) and 97.4% (37/38) (chi2=61.47, P<0.01) respectively.

CONCLUSIONSPathological features of early stage and late stage hepatitis C infection in transplanted livers are different and they are also different from that in native livers. Liver biopsies are important in clinical staging, evaluation of the severity, and differential diagnosis of post-transplantation HCV infection.