ABORhtyping

ABORhtyping is the process of determining an individual's blood group with respect to the ABO system and the Rh antigen status, typically abbreviated ABORh typing. It is a foundational procedure in clinical laboratories and is essential for safe blood transfusion, organ transplantation, and certain obstetric practices. The ABO system classifies red blood cells based on the presence or absence of A and B antigens, producing groups A, B, AB, and O. The Rh system mainly concerns the D antigen, yielding classifications of Rh positive or negative.

In standard practice, serologic testing uses forward typing, where patient red cells are exposed to anti-A, anti-B, and often anti-D reagents to determine surface antigens, and reverse typing, where patient plasma is tested for naturally occurring antibodies against A and B antigens. Additional testing may include weak D testing or extended Rh phenotyping for other Rh antigens (such as C, E, c, e) and, in some cases, molecular methods to resolve inconclusive results or evaluate neonatal samples.

Applications of ABORhtyping include ensuring compatibility in blood transfusions to prevent hemolytic reactions, guiding prenatal management to reduce the risk of hemolytic disease of the fetus and newborn, and supporting donor-recipient matching in transplantation. Limitations can arise from recent transfusions, autoimmune hemolysis, or unusual phenotypes, necessitating confirmatory testing and quality control. Advances include DNA-based typing, which can determine ABO and Rh status from genetic material and is particularly useful when serology is unreliable or unavailable.