effects of immunosuppressive therapy in a patient with aplastic anemiaparoxysmal nocturnal hemoglobinuria aapnh syndrome during ongoing eculizumab treatment a 65yearold woman experienced a hemolytic attack triggered by sepsis she presented with markedly increased cd55 cd59 erythrocytes and the signs of bone marrow failure which led to a diagnosis of aplastic anemiaparoxysmal nocturnal hemoglobinuria aapnh syndrome there was a possibility of increasing hemolysis as large pnh clones remained after immunosuppressive therapy ist accordingly eculizumab was first used to control the hemolytic attack followed by ist with antithymocyte globulin and cyclosporine a the patient was successfully weaned from blood transfusions and has been followed up without any recurrence of hemolytic attacks