PRODUCTION OF ANTI-D INDUCED BY RHD-NEGATIVE RED CELL TRANSFUSION IN A RHD-NEGATIVE PATIENT

We experienced a case in which an anti-D antibody was developed after transfusion of RBCs from 19 apparently D-negative donors over a half-year period beginning in July 2000. The patient was 67-year-old. B-negative female with a history of sensitization by transfusion of D-positive RBCs. Antibody screening became positive and an anti-D was detected by indirect antiglobulin testing. However, no hemolytic episodes due to the anti-D were found in her clinical course. Specificity of the antibody was confirmed as an allo-anti-D by serological studies using differential absorption-elution or dithiothreitol-treated RBCs. We initially suspected the possibility of transfusion from D-positive or weak D donors and the Rh phenotypes of all 19 donors were back-checked. However, none was positive for D antigen by the indirect antiglobulin test and 5 donors included Ce haplotype. Genomic analysis to detect a Del, allele will demonstrate whether RBCs from a donor carrying a Del allele with Ce haplotype induced an allo-anti-D immune response.