[Abstract] [Objective] To analyze the production of platelet antibodies in children with congenital heart disease, identify the types of antibodies, and explore their effects on platelet count, coagulation function and platelet function. [Methods] A retrospective analysis was conducted on 3 504 congenital heart disease patients without a history of blood transfusion who were treated at Beijing Children's Hospital between January 2019 and June 2024 to study the positive rate of platelet antibodies. Platelet antibody types were detected using the solid-phase agglutination method, and the platelet count and coagulation function of the children were analyzed. The impact of platelet antibodies on platelet function was evaluated using a coagulation and platelet function analyzer. [Results] The positive rate of platelet antibody in children with congenital heart disease with no history of blood transfusion was 9.7% (341/3 504), higher than the overall positive rate of 6.6% (2 657/40 311) in the general pediatric population. The platelet antibodies in congenital heart disease cases with positive platelet antibodies were mainly autoantibodies. There was no significant difference in platelet count between antibody-positive children and antibody-negative children. However, the prothrombin time (s) of antibody-positive children was significantly longer than that of antibody-negative children[(12.19±1.07) vs (11.32±0.77)]. Platelets sensitized by antibodies showed a significant reduction in function compared to non-sensitized platelets. [Conclusion] Children with congenital heart disease have a high rate of positivity for autoantibodies, which are associated with abnormalities in coagulation function and can lead to reduced platelet function.

【Objective】 To investigate the transfusion effect of 0.5-dose of apheresis platelet in pediatric patients. 【Methods】 A total of 195 children who underwent 0.5-dose platelet transfusion from August 2021 to June 2022 were enrolled, and the platelet count within 24 hours before and after platelet transfusion were recorded. They were grouped by gender, disease type, blood product transfusion history, platelet antibody results, platelet storage time and weight to analyze the effect of platelet transfusion. 【Results】 Among 195 cases, 77.4% (151/195) were effective and 22.6% (44/195) were ineffective after 0.5-dose of platelet transfusion. Platelet transfusion more than three times has significant impact on the effectiveness of platelet transfusion, with platelet transfusion efficiency decreased from 80.8% to 65.9% (P<0.05), and CCI decreased from 11.56±8.94 to 8.52±8.42 (P<0.05). The transfusion effect of the HLA and HPA antibodies positive group was significantly lower than the negative group, with CCI decreased from 11.39±8.87 to 7.82±8.59 (P=0.05). Linear regression analysis showed that the effect of platelet transfusion decreased with the increasing of platelet storage time (P<0.05), and the effect of platelet transfusion decreased in children weighing less than 20 kg compared with those weighing more than 20 kg, with the effective rate decreased from 84.1% to 63.5% (P<0.05). Different gender, disease type and the number of red blood cell transfusions had no significant effect on platelet transfusion. 【Conclusion】 The 0.5-dose platelet transfusion has good therapeutic effect in children below 20 kg. The results of HLA and HPA antibodies and the number of platelet transfusions greatly influence the effect of platelet transfusion in children, and the transfusion effect decreases with the increase of platelet storage time.

Objective: To evaluate the platelet transfusion requirements in children with high-risk stage Ⅳ neuroblastoma undergoing autologous hematopoietic stem cell transplantation (ASCT), and to identify risk factors for increased transfusion needs and prolonged time to platelet transfusion independence. Methods: This single-center retrospective clinical study included 96 children with high-risk stage Ⅳ neuroblastoma who underwent ASCT from January 2019 to May 2024 in our hospital. Relevant clinical data were collected and analyzed, including age, gender, body surface area, platelet count (PLT) on stem cell infusion day (day 0), conditioning regimen, CD34 stem cell dose, platelet transfusion requirements during transplantation, and time to platelet transfusion independence post-transplant. Results: All 96 (100%) children received transfusion after ASCT. From day 0 to transfusion independence, the median number of platelet transfusion was 3 (2, 4.50), and the median volume of platelet transfused was 3 (2, 4.25) units. Platelet transfusion was required in almost all children in pseudo-healing stage (day 4 to day 6) and polar stage (day 7 to day 14), with transfusion rates as high as 83.33%(n=80) and 100%(n=96), respectively. The median time to platelet transfusion independence post-transplant was 13(11,17) days. Multivariate analysis showed that PLT<100×10 /L on day 0, platelet transfusion within one week before ASCT, the use of “busulfan+ melphalan” conditioning regimen, and CD34 stem cell dose<4.0×10 /kg were associated with significantly increased platelet requirements and numbers of transfusion (P<0.05). PLT<100×10 /L on day 0, platelet transfusion within one week before ASCT, and CD34 stem cell dose<4.0×10 /kg were associated with significantly delayed platelet transfusion independence (P<0.05). Age, sex, and blood type showed no statistically significant association (P>0.05) with post-transplant platelet transfusion requirements or time to transfusion independence in neuroblastoma patients. Conclusion: This study provided quantitative data for platelet transfusion after ASCT in children with high-risk stage Ⅳ neuroblastoma, and identified PLT<100×10 /L on day 0, platelet transfusion within one week before ASCT, CD34 stem cell dose<4.0×10 /kg were risk factors for increased platelet transfusions and delayed transfusion independence. Furthermore, the use of the BuMel (busulfan-melphalan) conditioning regimen was also found to contribute to increased transfusion requirements.

Objective: To evaluate the platelet transfusion requirements in children with high-risk stage Ⅳ neuroblastoma undergoing autologous hematopoietic stem cell transplantation (ASCT), and to identify risk factors for increased transfusion needs and prolonged time to platelet transfusion independence. Methods: This single-center retrospective clinical study included 96 children with high-risk stage Ⅳ neuroblastoma who underwent ASCT from January 2019 to May 2024 in our hospital. Relevant clinical data were collected and analyzed, including age, gender, body surface area, platelet count (PLT) on stem cell infusion day (day 0), conditioning regimen, CD34 stem cell dose, platelet transfusion requirements during transplantation, and time to platelet transfusion independence post-transplant. Results: All 96 (100%) children received transfusion after ASCT. From day 0 to transfusion independence, the median number of platelet transfusion was 3 (2, 4.50), and the median volume of platelet transfused was 3 (2, 4.25) units. Platelet transfusion was required in almost all children in pseudo-healing stage (day 4 to day 6) and polar stage (day 7 to day 14), with transfusion rates as high as 83.33%(n=80) and 100%(n=96), respectively. The median time to platelet transfusion independence post-transplant was 13(11,17) days. Multivariate analysis showed that PLT<100×10 /L on day 0, platelet transfusion within one week before ASCT, the use of “busulfan+ melphalan” conditioning regimen, and CD34 stem cell dose<4.0×10 /kg were associated with significantly increased platelet requirements and numbers of transfusion (P<0.05). PLT<100×10 /L on day 0, platelet transfusion within one week before ASCT, and CD34 stem cell dose<4.0×10 /kg were associated with significantly delayed platelet transfusion independence (P<0.05). Age, sex, and blood type showed no statistically significant association (P>0.05) with post-transplant platelet transfusion requirements or time to transfusion independence in neuroblastoma patients. Conclusion: This study provided quantitative data for platelet transfusion after ASCT in children with high-risk stage Ⅳ neuroblastoma, and identified PLT<100×10 /L on day 0, platelet transfusion within one week before ASCT, CD34 stem cell dose<4.0×10 /kg were risk factors for increased platelet transfusions and delayed transfusion independence. Furthermore, the use of the BuMel (busulfan-melphalan) conditioning regimen was also found to contribute to increased transfusion requirements.