Autoimmune hemolytic anemia predominantly associated with IgA anti-E and anti-c

A patient with warm autoimmune hemolytic anemia (AIHA) due to predominance of immunoglobulin A (IgA) with an Rh specificity, considered to be the first case in Korea, is described. A 13-year-old male patient with severe hemolytic anemia showed a weak reactivity (1+) in the direct antiglobulin test (DAT) by using anti-IgG antiglobulin reagent. This finding, however, could not fully explain the patient's severe AIHA. When anti-IgA reagent was used for the DAT, strong reactivity (4+) was observed and free anti-E and anti-c autoantibodies were also detected by anti-IgA and anti-IgG reagents. The patient's hemoglobin began to rise with the administration of steroids. Because RBCs coated with multiple types of immunoglobulins are associated with more severe hemolysis than those only with IgG, the DATs using anti-IgA and other reagents are needed for the correct diagnosis when the result of DAT is not compatible with patient's clinical manifestations.