[A case of severe hemolytic disease of the newborn due to anti-Dia antibody].

Here we report a severe case of hemolytic anemia of the newborn with kernicterus caused by anti-Di(a) antibody. A full term male infant was transferred due to hyperbilirubinemia on the third day of life. Despite single phototherapy, the baby's total bilirubin had elevated to 30.1 mg/dL. After exchange transfusion, total bilirubin decreased to 11.45 mg/dL. The direct antiglobulin test on the infant's red cells was positive. The maternal and infant's sera showed a negative reaction in routine antibody detection tests, but were positive in Di(a) panel cells. The frequency of the Di(a) antigen among the Korean population is estimated to be 6.4-14.5%. Anti-Di(a) antibody could cause a hemolytic reaction against transfusion or hemolytic disease of the newborn. We suggest the need for reagent red blood cell panels to include Di(a) antigen positive cells in antibody identification test for Korean.