Histological examination and evaluation of donor bile ducts received during orthotopic liver transplantation-a morphological clue to ischemic-type biliary lesion?

Ischemic-type biliary lesions (ITBL) belong to a group of biliary disorders that are regarded as the major complication in patients with orthotopic liver transplantation (OLT). We performed histological evaluation of donor common bile ducts received during OLT to find morphological clues to the pathomechanisms of ITBL. We investigated 93 grafts of 92 patients (recipients: mean age, 56.5 years; underlying disease: hepatocellular carcinoma (n = 45), alcoholic cirrhosis (n = 16), viral hepatitis with cirrhosis (n = 9), retransplantations (n = 9), others (n = 14); donors: mean age, 53.2 years). Donor common bile ducts were received after recirculation of the hepatic artery prior to biliary end-to-end anastomosis and routinely processed. Statistical evaluation was performed by chi-square analysis and multivariate analysis using a logistic regression model. With regard to ITBL (observed in 19.4 %), the following phenomena were found to be statistically relevant: necrosis of the bile duct wall, arteriolonecrosis, vascular lesions (such as subintimal edema), and intramural bleeding (P < 0.001, P < 0.001, P = 0.029, and P = 0.031, respectively). In logistic regression analysis, arteriolonecrosis was the only parameter with significance (P = 0.001). Based on these results on the morphology of the donor common bile duct, we conclude that these phenomena of vascular damage, reflecting microangiopathy, play a major role in the pathogenesis of ITBL.