Establishment and Utilization of a Transfusion Recipient Registry in Korea: Estimating the Frequencies of Specific Antigen-Negative Blood Units.

Objectives: This study was conducted to establish the Korean national registry, to evaluate the distribution of unexpected antibodies, and to determine the frequencies of specific antigen-negative blood units. Methods: Data added to the Korean national registry between July 2013 and April 2016 were analyzed. The distribution of unexpected antibodies and frequencies of specific antigen-negative blood units were estimated. Results: In total, 3,513 cases from 22 institutes were registered. The most common single alloantibodies were anti-E, anti-Le(a), and anti-M. The most common multiple alloantibodies were anti-E with anti-c, anti-C with anti-e, and anti-Le(a) with anti-Le(b). The frequencies of E-, Le(a)-, and M-negative units were 42.3%, 56.9%, and 20.2%, respectively. Conclusions: The distribution of unexpected antibodies and frequencies of specific antigen-negative blood units were investigated using data from the Korean national registry. The results provide useful data to predict the number of blood units to be tested to obtain compatible blood units.