We present a case history of a 25-year old male after liver transplantation in 1999 due to cryptogenic cirrhosis with prolonged worsening of graft function, who developed haemolytic uremic syndrome (HUS). Because of unsatisfactory graft function numerous graft biopsies were performed. Signs of acute (AR) and chronic liver rejection (CR) were histopathologically confirmed. Vanishing bile duct syndrome as manifestation of CR was detected and immunosuppressive regimen was intensifi ed (tacrolimus replaced cyclosporine). High tacrolimus blood levels were maintained (ca 20-22 ng/ml). No clinical effect was observed. Faced with absence of other treatment possibilities, after four months, patient was referred to our centre in order to estimate indications for liver re-transplantation. On admission patient was in poor general condition; severe haemolytic anaemia, thrombocytopenia and acute renal failure were diagnosed. Atypical HUS probably related to  calcineurine inhibitor (CNI) was established. Tacrolimus administration was discontinued. Blood and plasma transfusion and plasmapheresis were implemented. Haemolysis was limited, but renal function had not improved. Renal biopsy revealed signs of irreversible nephropathy as a result of thrombotic microangiopathy. Nevertheless, previously maintaining high dose of  CNI, there were no signs of CNI nephropathy. Patient required haemodialysis. Subsequently liver biopsy was performed, what revealed CR. Due to necessity of haemodialysis and worsening of liver graft function, patient was accepted to (simultaneous) liver and kidney transplantation. Three months later patient died on the waiting list as a result of bleeding from the gastrointestinal tract.
Conclusions: High CNI blood concentration in patient after liver transplantation can be atypical cause of HUS and may lead to irreversible renal failure.

Keywords: Liver Transplantation, case report, clinical outcome