The paper presents the case of a 23 years old patient diagnosed with thrombotic thrombocytopenic purpura on the basis of increased body temperature, thrombocytopenia, microangoipathic hemolytic anemia, renal function disorders and a rapid development of coma after the epileptic seizure of Jacsonian type. The treatment included the therapy with antithrombocytic drugs such as lysin acetysalicylate, dipridamol, methylprednisolon, and other symptomatic and substitutional therapies. Fifteen therapeutic plasmaphereses were made with the replacement of 33.150 ml of plasma substituted with albumin and freshly frozen plasma (20.080 ml totally). The applied therapy gradually improved patient's neurologic finding. The patient was discharged from the hospital with normal neurological finding and magnetic resonance of the brain. In the conclusion we emphasize the importance of therapeutic replacement of plasma with the infusion of freshly frozen plasma, antithrombocytic therapy and the application of corticosteroids in the treatment of thrombotic thrombocytopenic purpura.