REFRACTORINESS TO PLATELET TRANSFUSIONS IN CHILDREN WITH ACUTE-LEUKEMIA

Purpose: We evaluated the incidence of clinically significant refractoriness to platelet transfusions in children with acute leukemia. Patients and Methods: We reviewed the complete transfusion records up to July 1993 of all 213 patients diagnosed with acute leukemia at our institution over the 4-year period 1987 to 1990. The transfusion protocol called for all patients requiring transfusion of red cell and/or platelet concentrates to initially receive components that were not leukocyte reduced. Patients suspected clinically to be refractory to platelets were tested for anti-human leukocyte antigen (HLA) antibodies and those that tested positive were switched to HLA-matched platelets. Results: Of 184 patients diagnosed with acute lymphoblastic leukemia(ALL), 133 (72%) required platelet support, whereas all 29 patients with acute myeloid leukemia (AML) were transfused with platelets. The incidence of clinically suspected refractoriness to non-leukocyte- reduced platelets, which was confirmed by a positive test for anti-HLA antibodies and which resulted in a switch to HLA-matched platelets, was nine of 29 (31%) for patients with AML but only three of 133 (2.3%) for patients with ALL. Conclusions: The results of this study indicate that clinically significant platelet refractoriness requiring transfusion of HLA-matched platelets occurs infrequently in childhood ALL. For this group of patients, use of leukocyte-depleted cellular components for the purpose of preventing platelet refractoriness cannot be justified. This approach may be appropriate for children with AML.