Anti-D Alloimmunization by Asian-Type DEL in Blood Transfusion

Abstract

Asian-Type DEL phenotype is a common type of Del phenotype found in Asian populations. It results from very low expression of the RhD antigen, primarily associated with a mutation in the RHD gene at position 1227 of exon 9, changing from Guanine (G) to Adenine (A) (c.1227G>A). This leads to very low expression of the D antigen compared to Rh-positive individuals, with only about 3,000 loci per red blood cells. Standard serological tests yield negative results, similar to Rh(D)-negative blood. Only adsorption-elution or molecular techniques can differentiate Asian-Type Del phenotype from Rh negative patients. This article aims to study research reported on anti-D alloimmunization from Rh DEL phenotype blood transfusions in Rh negative patients. This is crucial for guiding blood transfusion strategies, preventing antibody production, and efficiently managing blood resources. The study compiled published research data from PubMed and Scopus databases using the keywords Rh negative, Asian-Type DEL, Del phenotype and alloimmunization. Studies have shown that Rh negative patients, particularly those in Asian countries, can develop anti-D alloimmunization against antigen D by receiving Asian-Type DEL blood transfusions. Screening to distinguish Asian-Type Del donors from true D-negative is therefore crucial. Furthermore, studies have not found primary or secondary anti-D alloimmunization in Asian-Type Del individuals from Rh-positive blood exposure. Considering Rh-positive blood transfusions for Asian-Type Del patients is thus a promising future approach, pending further research. This approach would benefit patients by providing faster blood transfusions, reducing waiting times for scarce blood, and would also improve blood services by managing the shortage of Rh-negative blood. It also benefits in blood collection and transfusions service to maximize the utilization of available RhD-negative blood resource. Furthermore, it also brings benefit to blood services in managing the scarcity of RhD-negative blood to maximize benefits for patients.

Keywords: Rh Negative, Rh Del Phenotype, Asian type Del, alloimmunization