Limitations of the immediate spin crossmatch when used for detecting ABO incompatibility

In the eleventh edition of the AABB's Standards for Blood Banks and Transfusion Services the requirement for an antiglobulin crossmatch was deleted if no clinically significant unexpected antibodies are detected in recipient serum testing and if there is no history of detection of such antibodies. Test methods that demonstrate ABO incompatibility remain a requirement; however, the means to accomplish this may prove controversial. The immediate spin crossmatch has been used for the purpose of detecting ABO incompatibility by many workers. Nonetheless, limitations of this technique became apparent in tests between A2B donor red cells and group B patient sera. The results of 204 of 531 immediate spin crossmatches, between these two blood groups, were found to be negative.