Serum total bile acids monitoring after experimental orthotopic liver transplantation

The aim of this study was to evaluate the usefulness of serum total bile acids estimation in monitoring liver allograft recipients. To this end frequent blood samples and simultaneous needle biopsies of the liver were taken after orthotopic liver transplantation in unimmunosuppressed pigs. Serum bile acids were found to rapidly increase during the anhepatic phase of the transplantation procedure and to decrease after implantation of the liver graft. A normal serum bile acids level in the early postoperative phase was indicative of a technically successful transplantation procedure. A total of 28 successful transplantations was performed. Six recipients accepted the allograft without any histological sign of rejection. In 18 pigs the liver was rejected, the survival time of these animals ranged from 6 to 80 days. Four animals showed a transient rejection episode during the first months after transplantation. In nonrejecting animals serum bile acids remained undisturbed during the entire 4-month study period. In all cases of rejection serum bile acids promptly increased to very high levels of 100 to 700 mumol/liter (reference range 1 to 14 mumol/liter). Serum bile acids were found to be superior to standard liver function tests in detecting the process of liver rejection at an earlier stage. These results indicate that serum total bile acid estimation is a simple and useful test to monitor liver allograft recipients.