Histopathological features of hepatitis C in renal transplant candidates

Background. Although hepatitis C virus (HCV) infection is common in renal t ransplant candidates, its clinical significance remains unclear in this pop ulation, Little detailed information is available about the histological se verity of HCV infection in these patients. We evaluated the liver biopsy fe atures of chronic HCV in a large population of renal transplant candidates and investigated associations between histopathological changes and host- a nd virus-related factors. Methods. Thirty-seven patients seropositive for anti-HCV with chronic renal failure (CRF) referred to UCLA Medical Center for kidney or kidney/liver t ransplantation during the period 1992-1997 were included. HCV genotype and viral load were measured. A multivariate analysis: by logistic regression m odel was performed: age, gender, race, HCV load and genotype, CRF level, as partate and alanine aminotransferase activity, duration of HCV infection, u nderlying nephropathy, and alcohol abuse were independent variables; liver histology score was assumed a dependent variable. Results. Liver disease was present in all HCV-infected patients. Logistic r egression analysis revealed that histological damage was (P=0.0017) indepen dently associated with the CRF level; the severity of liver disease, as sho wn by univariate analysis, being significantly higher in CRF patients not r equiring dialysis than among dialysis population. All patients on dialysis showed mild or moderate necroinflammatory activity; the majority (22/28=79% ) of these individuals had fibrosis, three (3/28=11%) dialysis patients had established cirrhosis, Thirty-one (84%) of 37 patients were tested by poly merase chain reaction, 25 (81%) patients had detectable HCV RNA in serum, t he mean HCV load among viremic patients was 10.9 x 10(5) copies/ mi. The mo st frequent HCV genotypes were 1a (8/24=33%) and 1b (7/24=29%), followed by genotype 2b (3/24=12%). Conclusions. Pathological changes on liver biopsy were observed in all HCV- infected patients awaiting renal transplantation. The severity of histologi c damage observed on liver biopsy was less in dialysis than predialysis CRF patients. All dialysis patients had mild or moderate necroinflammatory act ivity; fibrosis was frequent with 11% of them having cirrhosis. The HCV vir al load was rather low; no relationship between liver histology changes and virological features of HCV or aminotransferase activity was apparent. Fur ther studies with repeat liver biopsies after kidney transplantation to obs erve the evolution of HCV-related liver disease after immunosuppressive the rapy are indicated, We suggest including liver biopsy in the evaluation of the HCV-infected renal transplant candidate.