[Report of two operated cases with erythrocyte antibody].

Two operated cases with erythrocyte antibodies were reported. In the first case who required the second open heart operation for mitral stenosis, delayed hemolytic transfusion reaction by erythrocyte antibodies was recognized. The direct and indirect Coombs' tests were negative and the erythrocyte antibodies were not detected preoperatively. Massive blood transfusion during perioperative period precipitated secondary immunoreaction and reproduction of antibodies. An anti-c antibody and anti-E antibody were detected by the serologic studies on the 11th and 16th postoperative day. In the second case, stenotic mitral valve was replaced without homologous blood transfusion, because anti-C antibody was detected preoperatively. We believe that open heart operations without blood transfusion should be done, whenever possible, it should be kept in mind that delayed hemolytic transfusion reaction by erythrocyte antibody may occur after blood transfusion.