Postoperative encephalopathy after orthotopic liver transplantation can be difficult to diagnose. We report a case of heparin-induced thrombocytopenia in a liver transplant patient who had seizures. Due to poor liver function the patient developed hepatorenal syndrome requiring continuous veno-venous hemodialysis (CVVHD). Initially we used heparin as the anticoagulant. After the diagnosis of heparin-induced thrombocytopenia (HIT) was made, we switched to r-hirudin. No serious side effects, e.g. bleeding or immune sensitization, were seen.