Antibodies to low-incidence antigens and elimination of the antihuman globulin phase of the crossmatch—case report: Anti-Wr^a

An antibody to a low-incidence antigen was identified in the serum of a nontransfused male patient. The antibody was subsequently identified as anti-Wr^a and was only detectable at the antihuman globulin (AHG) phase of the crossmatch. Instances of severe hemolytic transfusion reactions have been reported following the transfusion of red blood cells containing low-incidence antigens in patients with antibodies directed toward these antigens (e.g., anti-Wr^a, -Co^b, -Js^a, etc.). Elimination of the AHG phase of the crossmatch can result in either risks or benefits. Since patients seen at this facility primarily have been multitransfused or are multiparous females, the AHG phase of the crossmatch has been maintained.