Erythrocyte Alloimmunization and Autoimmunization in the Pediatric Population: A Multicenter, Cross-Sectional Study in Central China.

Background: Erythrocyte alloantibodies and autoantibodies complicate transfusion. However, the prevalence of erythrocyte alloimmunization and autoimmunization has not been estimated in the Chinese pediatric population. Therefore, we investigated the prevalence of erythrocyte alloimmunization and autoimmunization in the Chinese pediatric population with the aim of developing a reasonable transfusion management policy in children from China.

Methods: This study included 30,603 pediatric inpatients who were admitted to three tertiary hospitals in central China from May 2020 to October 2022. Antibody screening was carried out with a three-cell panel by column agglutination technology, and samples with positive screening were analyzed for antibody specificity with a 16-cell identification panel. Clinical details of the patients were collected to identify associations with antibody formation.

Results: The alloimmunization rate was 0.55% (169/30,603), and the autoimmunization rate was 0.14% (43/30,603). Alloantibodies comprised 80.09% of the antibodies. The most frequent alloantibodies were anti-M (58.77%), anti-E (9.48%), and anti-P1 (4.27%). Autoantibodies comprised 19.91% of antibodies. Age (p = 0.000), sex (p = 0.016), geographical area (p = 0.000), ABO blood group (p = 0.008), and diagnosis (p = 0.000) were independent risk factors for antibody formation. The risk of antibody formation at the ages of 0-28 days and 1-3 months was zero (odds ratio = 0.000). The antibody distribution was significantly different by age (p = 0.000) and diagnosis (p = 0.000).

Conclusion: Repeat pre-transfusion testing for infants less than 4 months of age can be omitted for no risk of antibody formation. MNS system antibodies, especially anti-M, are prominent in younger children, and this decreases with age. Provision of extended phenotype-matched transfusion for Rh system antigens, especially antigen E, is necessary in children to control erythrocyte alloimmunization. The presence of antibodies with high evanescence rates in the pediatric population suggests the pressing need for nationwide shared transfusion records to avoid hemolytic transfusion reactions in children.