Reasoning, clinical aspects, and results of a guarded platelet substitution therapy in children with acute lymphoblastic and myeloblastic leukemia treated according to the BFM therapy studies

In this retrospective study of 62 children with ALL and 10 children with AML, data are compiled on the special aspects of a guarded indication for platelet transfusions; in Tubingen this indication is usually based solely on clinical signs of incipient or manifest bleeding at platelet counts below 11,000/mm3. This is in contrast to the practice most often used to transfuse platelets at counts below 20,000/mm3 for prophylactic reasons irrespective of therapeutic need. The guarded indication aims at keeping the rate of allosensitization by platelet transfusions as low as possible. Of all patients in remission induction of ALL and of AML, platelet transfusions were needed by 53% and 80% respectively; the mean platelet support was 2.9 units in ALL and 19.0 units in AML. In relapse, the need increased considerably. Of all patients with ALL, 11% were sensitized by platelet transfusions; lethal complications related to this guarded indication could not be seen.