Transfusion Reactions in Pediatric and Young Adult Hematopoietic Stem Cell Transplant and Oncology Patients

Background Patients undergoing chemotherapy and especially hematopoietic stem cell transplantation (HSCT) require frequent transfusions, and thus, transfusion reaction (TR) vigilance is critical in this population. The reported incidence of TRs across all patients is 2%, and pediatric patients may experience 2-2.6 times more reactions than adults. However, the TR profile may differ in the immunocompromised population. There is a paucity of data in this area, as pediatric oncology and HSCT patients are often excluded from TR studies. Our goals were to assess the prevalence and describe TRs among immunocompromised pediatric patients and to improve recognition of TRs across this population. Methods Pediatric clinical providers completed a TR training module in May – June, 2019. A single-institution retrospective review was conducted. All TRs in patients aged less than 25 years were reviewed over a 3-month period from July 1, 2019 to October 1, 2019. Results Over a 3-month period, 1,786 transfusions were administered in our designated population. Of those, 50.4% were platelets, 44.0% were red blood cells (RBC), 3.4% were cryoprecipitate, 1.4% were thawed plasma, and 0.8% were granulocytes. Those undergoing HSCT consumed 27.7% of total transfusions. Of all transfusions, there were 48 (2.7%) reported as possible TRs by nursing. Of those, 30 (1.7% of all transfusions) were adjudicated as true TRs. Fourteen (46.7%) of these true TRs were in patients with leukemia, 9 (30.0%) with HSCT, 5 (16.7%) with solid tumors, and 2 (6.7%) with aplastic anemia. Of the 9 reactions in HSCT patients, 4 occurred in allogeneic transplant recipients (3 umbilical cord blood and one matched unrelated donor) and 5 were in those receiving autologous HSCT. In HSCT patients, 1.8% of transfusions resulted in TRs compared to 1.6% in non-HSCT patients. Of the products triggering reactions, platelets accounted for 22 TRs (73.3%) and RBCs accounted for 8 TRs (26.7%). Of all 30 TRs, 15 (50%) were classified as febrile non-hemolytic transfusion reactions (FNHTR), 14 (46.7%) were considered allergic reactions, and 1 (3.3%) was diagnosed as transfusion-associated circulatory overload. Pre-medication was given in 22 (76.7%) of transfusions causing reactions. Of the 18 reports that were not adjudicated as true TRs, most (n=15) were generated for fever, but deemed unrelated to transfusion. Conclusions Our baseline analysis revealed a higher prevalence than our historical institutional prevalence (1.7% vs. 1.3%), consistent with higher rates of TRs in the pediatric population, but lower than the 2% quoted in the literature, suggesting either underreporting or a different TR phenotype in this population. This population had a higher prevalence of FNHTR than the general pediatric population (50.0% vs. 31.5%). High rates of pre-medication and comorbidities (resulting in fevers) may influence TR presentation in this population.