Evaluating patients with autoimmune hemolytic anemia in the transfusion service and immunohematology reference laboratory: pretransfusion testing challenges and best transfusion-management strategies

The serologic evaluation of autoimmune hemolytic anemia (AIHA) confirms the clinical diagnosis, helps distinguish the type of AIHA, and identifi es whether any under ly ing alloantibodies are present that might com pli cate the selec tion of the saf est blood for any needed trans fu sion. The spec trum of test ing is gen er ally depen dent on the amount and class (immu no glob u lin G or M) of auto an ti body as well as the resources and meth od ol o gies where test ing is performed. The approach may range from rou tine pretransfusion test ing, includ ing the direct anti glob u lin test, to advanced tech niques such as adsorp tions, elu tion, and red cell genotyping. When trans fu sion is needed, the selec tion of the opti mal unit of red blood cells is based on urgency and whether time allows for the com ple tion of sophis ti cated sero logic and molec u lar test ing meth ods. From the start of when AIHA is suspected until the com ple tion of test ing, com mu ni ca tion among the clinical team and medical laboratory scientists in the transfusion service and immunohematology reference laboratory is crit i cal as test ing can take sev eral hours and the need for trans fu sion may be urgent. The fre quent exchange of infor-ma tion includ ing the patient ' s trans fu sion his tory and clin i cal sta tus, the prog ress of test ing, and any avail able results is invalu able for timely diag no sis, ongo ing man age ment of the patient, and the safety of trans fu sion if required before testing is complete.