Summary
A study of 42 thrombocytopenic neonates found that platelet transfusions increased platelet counts but did not significantly impact bleeding. However, transfusions were associated with increased inflammatory cytokines and neutrophil extracellular traps (NETs), which may contribute to negative outcomes. Another study investigated the impact of probiotics on gut microbiota after colonoscopy. The probiotic group, receiving Bacillus subtilis and Enterococcus faecium, showed improved gastrointestinal symptoms and microbiota composition compared to the placebo group.
Editor: Deborah Sesok-Pizzini, MD, MBA, adjunct professor, Department of Clinical Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia.
Effects of platelet transfusions on neonatal bleeding and inflammation
February 2026—Thrombocytopenia is a frequent finding for neonates admitted to the neonatal intensive care unit. Platelet transfusions are often given to preterm neonates to reduce their bleeding risk. Yet, some observational and randomized studies have reported that higher morbidity and mortality are associated with an increased number of platelet transfusions in neonates. The recent Platelets for Neonatal Transfusion (PlaNeT-2) trial of preterm neonates showed that such patients receiving platelet transfusions at a threshold of less than 50 × 109/L had a higher incidence of death or major bleeding than those randomized to the lower threshold of less than 25 × 109/L. Follow-up of patients in this trial also found a worse neurodevelopmental outcome at two years of age in infants who received a greater number of platelet transfusions. The mechanisms underlying these outcomes after platelet transfusion are unknown. It is thought that they may be related to the impact of platelets on immune and inflammatory responses and the differences between platelets from adults and neonates. Transfusion of platelets from adults into neonates may result in more interaction with monocytes and neutrophils, and adult platelets may be more immunologically active than those from neonates. The authors conducted a prospective cohort study to characterize the effects of platelet transfusion on clinical bleeding, plasma cytokines, and neutrophil extracellular trap (NET) levels in neonates. The study was conducted on thrombocytopenic neonates admitted to either of two NICUs between 2020 and 2024. Bleeding and platelet count were assessed. Blood was collected one hour before and two and four hours after platelet transfusion for evaluation of a plasma cytokine panel and NETs. Aliquots from transfused units were also collected. The results from 42 infants with severe thrombocytopenia showed that 68 platelet transfusions were administered. The transfusions increased the platelet count by 15 ± 3 × 109/L but had no significant impact on bleeding. Four hours after transfusion, levels of the potent chemokine RANTES (regulated upon activation, normal T cell expressed and secreted) increased 6.5 fold (p=.03) and were higher than expected compared with the quantity in the platelet aliquots tested. Furthermore, plasma NETs increased 1.24 fold (p=.0007) posttransfusion. The transfused units storage time and free mtDNA concentrations also correlated with RANTES increases (p=.04 and .03, respectively). The authors concluded that platelet transfusions were associated with increases in inflammatory cytokines and NETs in neonates. They noted that this may contribute to the negative outcomes associated with platelet transfusion. This study also identified novel transfusion-related inflammatory changes in neonates that may impact observed outcomes. These findings emphasize the need for additional studies t o characterize immunological effects of platelet transfusion on preterm and term neonates and the effects of modifiable blood bank interventions/storage time on neonatal outcomes.
Davenport P, Feldman HA, Young V, et al. Effects of platelet transfusions on neonatal bleeding and inflammation. Pediatr Res. 2025. doi.org/10.1038/s41390-025-04498-9
Correspondence: Dr. Patricia Davenport at patricia.davenport@childrens.harvard.edu