Difference of Rh Phenotype between Irregular Antibody Positive Patients and RhD Positive Population in Korea / 대한수혈학회지

ABSTRACT

BACKGROUND: The Rh system is the most important blood group after ABO in the transfusion field. Nearly half of irregular antibodies with specificity are related to Rh antigens in Korea. Formation of alloantibody for red blood cells is considered variable according to Rh phenotype of patients. We therefore studied the significance of Rh phenotype in Korean irregular antibody positive patients. METHODS: We performed retrospective reviews for the results of antibody identification tests performed from Jun. 2004 to Nov. 2013 in our university medical center. Rh phenotype, direct antiglobulin test, and antibody specificity were investigated. Rh phenotype was tested using RhD+ phenotype ID-card (DiaMed GmBH, Switzerland). RESULTS: A total of 504 patients were included. Of 504 patients, 495 (98.2%) were RhD positive. The proportion of Rh phenotype differed significantly between irregular antibody positive patients and known RhD positive Korean population in CDe phenotype (59.0% vs 39.4%, P<0.0001) and CcDEe phenotype (22.6% vs 38.4%, P<0.0001), respectively. The percentage of other Rh phenotype was not different in two groups. Formation of anti-E antibody in E negative patients was significantly higher than that of anti-C formation in C negative patients (P<0.0001). Sixteen patients showed antibodies with specificity for their own Rh system antigens. CONCLUSION: A significant disproportion of Rh phenotype was observed between irregular antibody positive patients and RhD positive Korean population. There would be a difference of immunogenicity among C/c and E/e antigens. E antigen matching might be considered first for patient required chronic transfusion if additional RBC matching would be implemented.