A fatal case of acute hemolytic transfusion reaction caused by anti-Wr^a: case report and review of the literature

Abstract The red blood cell (RBC) antigen Wr a is low-prevalence first described in 1953 by Holman and assigned to the Diego system 1995. Because of its low prevalence, usually absent on commercial screening RBCs antibody identification panels. When Wr(a+) are available, corresponding antibody, anti-Wr , often found sera from healthy individuals, patients, pregnant women. Anti-Wr can cause both hemolytic transfusion reactions disease fetus newborn. We describe fatal acute reaction caused patient with no other RBC alloantibodies. Serologic investigation showed that one units received was Wr(a+). Immunohematology 2021;37:20–24 .