Editor: Deborah Sesok-Pizzini, MD, MBA, adjunct professor, Department of Clinical Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia.
Platelet transfusion practices and outcomes in neonates and children
June 2026—Platelet transfusion in neonate and pediatric patients prevents or stops bleeding. Platelet donor characteristics, such as sex and age, and further processing and storage of platelet units may impact platelet increments, overall transfusion burden, and clinical outcomes in pediatric and neonate transfusion recipients. Platelet collection and processing steps vary across blood centers. In the blood bank, platelets for pediatric use sometimes undergo pathogen reduction or irradiation and may be stored in platelet additive solution. Insight into the clinical outcomes following transfusion of different platelet products, as well as donor characteristics, may help inform better transfusion practices in neonate and pediatric patients. The authors conducted a study to describe the epidemiology of platelet transfusions and the association of blood donor and platelet characteristics with post-transfusion platelet increments, transfusion burden, and clinical outcomes in the neonatal and pediatric populations. The large cohort study involved patients who were younger than 18 years old (with birth weights higher than 2,500 g) between April 1, 2019 and June 30, 2023 and in the Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P) program vein-to-vein multicenter, retrospective, donor-component-recipient-linked database. (The REDS-IV-P program was a seven-year endeavor funded by the National Heart, Lung and Blood Institute that ran from April 2019 through March 2026 and included seven blood centers and 22 hospitals, of which six were children’s hospitals.) Inpatient encounters for patients from newborn to 18 years old were included in the authors’ study, and infants less than 28 days old were considered neonates. A platelet transfusion event was defined as issuance of a platelet product by the transfusion service between an encounter start and end time. (Each hospital admission was considered a unique encounter.) Transfusion incidence was calculated for the total population, and patient sex, age, and self-reported race and ethnicity were recorded at each encounter. The characteristics of platelet products were described by percentages (the number with the characteristic divided by the total number of platelet products transfused, multiplied by 100). The Information Standard for Blood and Transplant (ISBT) code was used to determine the collection method. The product issue date and time, donation identification number, ISBT code, and aliquot code were used to link the transfused products to the donor or donation and blood center and hospital transfusion service data. Out of 249,340 inpatient encounters, platelet transfusion was reported in 8,874 (3.6 percent) patients (4,934 of 131,592 encounters). Platelet transfusion was lowest among children younger than one year old (2.6 percent) and highest among children one to less than six years old (4.7 percent; P<.001). Pathogen reduction, use of platelet additive solution, platelet storage duration longer than three days, male sex, and donor age 40 years or older were associated with lower platelet increments (all P<.001). Of interest, these donor and platelet factors were not associated with post-transfusion platelet increments and overall transfusion burden. Use of platelet additive solution, pathogen reduction, platelet storage longer than three days, and donor age 40 years or older were associated with a significantly higher overall platelet transfusion burden but were not associated with hospital length of stay or mortality. The authors concluded that the findings from this study have important implications for platelet transfusion practices among neonates and children, but further validation via well-designed prospective studies is needed.
Goel R, Karam O, Warden DE, et al. Platelet transfusion practices and outcomes in neonates and children. JAMA Network Open. 2026. doi.org/10.1001/jamanetworkopen.2025.54531
Correspondence: Dr. Ruchika Goel at rgoel71@siumed.edu
Red cell antibody and antigen patterns in patients with sickle cell disease
Sickle cell disease patients often require red blood cell transfusions to help maintain a lower sickle cell level and prevent complications, such as vaso-occlusive sickle cell crises and stroke. Yet an estimated five to 75 percent of frequently transfused sickle cell disease (SCD) patients will develop red blood cell (RBC) antibodies as a complication of transfusion support. Because of the incidence of alloimmunization, which can trigger delayed hemolytic transfusion reactions and hyperhemolysis, as well as anticipated future difficulty finding compatible blood, the majority of institutions have developed protocols for prophylactic RBC antigen matching of D, C, E, c, e, and Kell groups. These RBC antigens have been selected based on their immunogenicity. Sickle cell patients are most at risk for alloimmunization due to antigenic differences between a largely Caucasian blood donor base and a predominately African American patient base, increased inflammatory states, and a lifetime of transfusion support and donor exposures. Even with select antigen matching, it is unknown if there are regional differences with antigen frequency or antibody prevalence. The authors conducted a retrospective study to examine RBC antibody prevalence, co-occurrence, correlation with antigen status, and immunogenicity in 2,965 SCD patients treated at nine hospitals in various geographic regions of the United States from 2010 to 2022. The hospitals included in the study prophylactically matched for Rh and K antigens, and sites collected demographic data, antigen status, antibody histories, and antibody screening results from patients’ laboratory records. Of note, autoantibodies or nonspecific or inconclusive serological reactivities were included in the data and as a positive test result for antibody prevalence. The authors used descriptive statistics and chi-square tests (base R package) for the analysis. The study results showed the overall antibody prevalence to be 29.7 percent, with institutional variation of 17.9 to 56 percent. Alloantibody prevalence was 27.5 percent. Of interest, 74.23 percent of autoantibody-positive patients also had alloantibodies, which identifies a high-risk population for transfusion. About 33 percent of the patients with positive antibody histories had negative screens in later testing. The Rh and K antibodies were the most common and most likely to co-occur, followed by S, Fya, and Jkb antibodies. Regional antibody variations were noted, but the overall frequency of different antigens remained consistent. In a pairwise comparison, 3.15 percent of patients were antigen negative and antibody positive, correlating with alloimmunization. A total of 0.47 percent were antibody and antigen positive, which may suggest partial/variant antigens. The authors concluded that the institutional variation in antibody prevalence suggests a need to examine site-specific approaches for testing and prophylactic matching. The co-occurrence of autoantibodies, alloantibodies, and antibody immunogenicity patterns, as well as antigen–antibody discordance, support the need for further research to determine the best antigen-matching strategies for SCD patients.
Covington ML, Allen ES, Chou ST, et al. Red cell antibody and antigen patterns in patients with sickle cell disease: A multi-center analysis. Transfusion. 2026. doi.org/10.1111/trf.70213
Correspondence: Dr. Mischa L. Covington at mlcovington@bwh.harvard.edu