Sequential Liver Chemistry Profiling and Abdominal Ultrasound Assessments to Predict Biliary Strictures after Liver Transplantation

Background: After orthotopic liver transplantation (OLT) early detection of biliary strictures is important. Our aim was to evaluate the predictive value of routine serum liver chemistry profiling and abdominal ultrasound as non- invasive diagnostic tools in detecting biliary strictures after OLT. Methods: We performed a retrospective study in which 141 primary OLTs, performed between 1992 and 2007 with more than 1 year follow-up, were included. Routinely assessed serum levels of alkaline phosphatase, alanine-aminotransferase, aspartate-aminotransferase, gamma-glutamyl transpeptidase and bilirubin at 3, 6, 9 and 12 months, and abdominal ultrasounds performed at 3, 6 and 12 months after OLT were evaluated. All biliary strictures requiring intervention occurring after 3 months were included. Time-dependent Cox regression analysis was performed to identify predictive factors for the development of biliary strictures. Results: Eighteen grafts developed non-anastomotic strictures (12.8%) and 18 grafts (12.8%) developed anastomotic strictures requiring intervention. An elevated gamma-glutamyl transpeptidase (HR 1.24 per 100 IU/L; p = 0.05) and dilated bile ducts on ultrasound (HR 3.45; p < 0.01) were found to have an independent predictive value for the development of biliary strictures requiring intervention. Bilirubin and the other studied liver enzymes were not independently predictive. Conclusion: Dilated bile ducts on ultrasound and elevated gamma-glutamyltranspeptidase after OLT are independent predictive factors for the development of biliary strictures requiring intervention. Routine assessment by serum gGT and US at 3-month intervals during the first year post-OLT is useful to screen for biliary strictures post-OLT.