Idiopathic portal hypertension in a renal transplant patient after long-term azathioprine therapy.

We report the case of a patient with renal insufficiency who was admitted for the evaluation of splenomegaly. He had received a kidney allograft 6 1/2 years ago. Treatment with azathioprine and prednisolone for immunosuppression had been discontinued 1 year before admission. The underlying cause of the splenomegaly appeared to be an idiopathic portal hypertension. Until now, this disease has been described in only 13 kidney transplant patients receiving long-term immunosuppressive therapy with azathioprine. For the first time we demonstrate that azathioprine can cause this chronic liver disease even if the drug has been withdrawn some time before. Therefore, the indication for azathioprine must be considered very carefully.