INTRAHEPATIC BILE DUCT NECROSIS AS A CAUSE OF ALLOGRAFT FAILURE IN PATIENTS TRANSPLANTED FOR HEPATITIS C

Abstract

182 Introduction: Intrahepatic bile duct necrosis (IHBN) is an important contributing cause of allograft failure requiring retransplantation. Most cases of intrahepatic bile duct necrosis can attributed to: 1. hepatic artery thrombosis (HAT), 2. portal vein thrombosis (PVT), and 3. foam cell arteriopathy (chronic vascular rejection). We have noted a particularly large percentage of failed allografts due to IBDN in patients transplanted for cirrhosis due to HCV and decided to study the causes systematically. Methods: Histologic sections from all failed allografts removed at the time of first re-transplantation performed between 1992 and 1997 were reexamined. Cases were included in the study if the sections revealed necrosis of the large intrahepatic bile ducts near the hilum, resulting in bile sludging within duct lumens. The medical records of these patients were examined. Cases were excluded if there was any evidence of extrahepatic biliary strictures. Evidence of vascular thrombosis at the time of retransplantation or in pre-operative radiographic studies was noted. Results: Histologic sections from 122 failed first allografts were examined and 44 cases of IBDN were identified. In 31 of these 44 cases IBDN was attributed to HAT, PVT or chronic rejection. Among the remaining 13 cases 10 of the patients were transplanted for HCV, two for cryptogenic cirrhosis and one for autoimmune hepatitis. The mean cold ischemia time in these 10 cases was 10.75 hours. None of these lo HCV cases had any of the histologic features of recurrent HCV infection, "fibrosing cholestatic hepatitis", or of chronic vascular rejection in any biopsy or in the failed graft. Conclusions: Of the 84 patients transplanted at our center for cirrhosis due to HCV 23 have required re-transplantation, and 10 of those exhibited IBDN without identifiable cause, making it a major cause of allograft failure in this group. Of the remaining 13 without IBDN only one was due to cirrhosis due to recurrent HCV. Thirty percent of allografts fail due to IBDN of unknown cause, and 77% of these cases occur in patients transplanted for HCV.