Analysis of Allergic Transfusion Reactions at a Children's Tertiary Care Center

Background: Transfusion reaction adverse events are a relatively rare occurrence in the United States. This is due to specific blood safety measures such as appropriate collection, preparation, testing, storage, and distribution of blood components as well as appropriate monitoring of patients receiving these transfusions. Several years of data have been collected by our institution's blood bank. Through our analysis, we have been able to describe the rate of transfusion- associated adverse events in pediatric patients at Children's Hospital of Michigan from 2018-2022.

Objectives: The aim of this retrospective chart review was to assess the rate of allergic blood transfusion complications and reactions among pediatric patients at Children's Hospital of Michigan in Detroit, Michigan.

Materials and Methods: An institution-based retrospective chart review was conducted for a total of 43,210 transfusions over a span of five years from 2018-2022.

Results: There were a total of 43,210 transfusions. A total of 26,669 of these products were red blood cell (RBC) transfusions, 10,447 were platelets, 4,392 were plasma, and 1,702 were cryoprecipitate (combined plasma and cryoprecipitate was 6,094). A reported reaction was encountered in 176 of the 43,210 transfusions. These reported reactions were part of the patients' underlying diseases. A true acute transfusion reaction (ATR) was encountered in 116 of the 43,210 transfusions. Of the 116 transfusions, 66 (56.9%) were classified as allergic reactions. About 61% of those reactions were skin manifestations (urticaria, itching), 9% were respiratory symptoms (dyspnea, tachypnea), and the remaining 30% were both skin and respiratory symptoms.

Of the total amount of RBC transfusions, 35 (0.131%) resulted in an allergic reaction. Similarly, 19 (0.182%) platelet and 12 (0.197%) plasma transfusions resulted in ATRs. ATRs were most associated with plasma, followed by platelets and RBC transfusions. Combining all transfusions received, these represented a total of 66 (0.153%) allergic transfusion reactions. These results are demonstrated in Figure 1.

Conclusion: ATRs were observed in 0.268% of total transfusions (allergic reactions (0.153%) and other reactions (0.115%)) that occurred over the course of five years at our institution. This is about 1 in 655 blood components transfused that was associated with an allergic reaction (more commonly with plasma > platelets > packed RBCs). The rate of allergic reactions is less than what was reported by National Blood Collection and Utilization Survey 2017 (0.282%). This rate is also less than what is reported for children (0.53%) and adults (0.26%) in a meta-analysis (Wang Y, Sun W, Wang X, et al. Comparison of transfusion reactions in children and adults: A systematic review and meta-analysis. Pediatr Blood Cancer. 2022;69(9):e29842.). These lower rates could be secondary to changes in blood processing and under-reporting.