Development of anti‐D in a severe delayed hemolytic transfusion reaction due to <scp>DAU3</scp> , a partial D variant allele

This case highlights the importance of timely identification and reporting of delayed transfusion reactions, especially in the context of prior sensitization events. Additionally, careful investigation of serologic patterns to identify partial D variants is important to optimize the clinical management of affected patients in the case of trauma, obstetrics, or operative care. We suggest the necessity of molecular testing in high-exposure patient populations to prevent adverse outcomes from unexpected allo-anti-D development.