Erythrocyte antigens and antibodies in the Chilean population

Chile does not have a national registry of immunohematologic test results; there are no data on the prevalence of erythrocyte antigens and the frequency of antibodies in this population. Therefore, foreign references are used for decision-making. In this study, a standard questionnaire was used in 74 laboratories of public and private establishments. The information from tests conducted in 2015 was requested: ABO and D typing, antibody detection, antibody identification, and erythrocyte phenotype. Prevalence for the ABO-D phenotypes were obtained at the country level (D+ [94.4%] and D– [5.5%]) and differ from those recorded in the white population (85% and 15%, respectively). Positive antibody detection results were found in 0.4 and 1.3 percent of blood donors and patients, respectively; the main specificities were anti-Le^a, -E, and -D in donors and anti-D, -E, and -K in patients. Inconclusive results were observed in ABO-D typing and antibody identification in donors and patients; these samples were referred to immunohematology reference laboratories for resolution. From this study, it was possible to estimate the prevalence of erythrocyte antigens and the frequency of antibodies at the national level, and this step allows us to characterize Chile’s population of blood donors and transfusion recipients and to compare the results and frequencies with other populations or countries.