Background/aims: In patients after orthotopic liver transplantation, treatment with the novel immunosuppressant FK 506 may lead to elevated levels of alkaline phosphatase, gamma glutamyl transferase and bilirubin. Up to now it was unclear whether the excretory capacity of the liver in such patients is impaired.
Methods: We measured quantitatively the secretion of bile acids, phospholipids and cholesterol using the duodenal perfusion method, which allows assessment of biliary secretion without interruption of the enterohepatic circulation. Six healthy volunteers served as controls.
Results: All patients studied after orthotopic liver transplantation had elevated concentrations of serum alkaline phosphatase and gamma glutamyl transferase, whereas only half of them had slightly abnormal serum bilirubin levels. On average, the FK 506-treated patients excreted 1.23 +/- 0.27 mmol/h bile acids, 0.23 +/- 0.04 mmol/h phospholipids and 0.11 +/- 0.02 mmol/h cholesterol, which was not significantly different from the healthy controls.
Conclusions: The normal secretion rates of biliary bile acids and lipids in FK 506-treated patients with elevated serum alkaline phosphatase and gamma glutamyl transferase indicate that the excretory capacity of the transplanted liver has completely recovered 2-3 months after surgery. In addition, in the majority of these patients elevated serum levels of alkaline phosphatase, gamma glutamyl transferase and bilirubin do not reflect impaired biliary secretion.