Early detection of graft dysfunction after orthotopic liver transplantation in man by serum and biliary bile acid analysis

Background/Aims: Several routine parameters are used to monitor the functional state of the Liver after orthotopic liver transplantation (OLT). These parameters may not fully mirror hepatic function and even liver biopsy may be unreliable during onset of graft rejection. Additional analytical methods on bile constituents for recognition of early graft dysfunction have been assessed. Conflicting results have prompted discussions about the usefulness of monitoring serum bile acids and biliary Lipids after OLT with respect to early recognition of graft dysfunction. Materials and Methods: Routine serum Liver function, tests were compared with serum bile acid (BA) concentrations and output of biliary lipids (BA, phospholipids, cholesterol) over 20-25 days in 12 patients after (OLT) with different postoperative courses. Results: 4 patients had an uneventful postoperative course (group 1); 5 experienced a rejection episode (group 2); 3 demonstrated a poor initial graft function (group 3). In group 1 aspartate-aminotransferase (AST) (<20 U/L), urinary BA excretion (<21 mmoles/day) and normalized bile flow (NBF; 72+/-25 ml bile/mmole BA) fell into the normal range within 4 days after OLT; serum BA concentration (<20 mM) was within normal on, the first postoperative day. Output of biliary BA, phospholipids, cholesterol and bile production increased continuously during the observation period reaching values of 11.2+/-3.3 mmoles/day, 2.7+/-0.9 mmoles/day, 1.3+/-0.5 mmoles/day and 761+/-221 ml/day, respectively. The ratio of taurocholate/glycocholate (TC/GC) decreased from an initial value of 0.45 to 0.11. Group 2 yielded similar values until rejection appeared. At this time serum BA concentration, NBF,urinary BA excretion and TC/GC-ratio rose; biliary lipid output and bile flow decreased. In most of the patients these changes occurred at the same day or 1-3 days earlier than, that of AST. Conclusions: The determination of serum BA concentration, TC/GC-ratio, output of biliary lipids and NBF may indicate graft dysfunction 1-3 days earlier than. AST and, thus, may provide useful parameters for early recognition of liver graft dysfunction.