Red cell alloimmunization in a transfused patient population: a study from a tertiary care hospital in north India

Abstract

Background: Red blood cell (RBC) alloimmunization results from genetic disparity of RBC antigens between donor and recipients. There is a paucity of data on the incidence of RBC alloimmunization in transfused recipients from the region studied, as pre-transfusion antibody screening is not routinely performed.Aim: To assess the incidence of RBC alloimmunization in a transfused patient population at a tertiary care hospital in north India.Materials and methods: Antibody screening was carried out in 531 multi-transfused patients prior to crossmatching with a commercially available three-cell panel (Diacell; Diamed AG, Cressier-sur-Morat, Switzerland) by the tube method, using a saline indirect antiglobulin test. Antibody screen-positive samples were analyzed for the specificity of the alloantibody with an 11-cell identification panel (Diapanel; Diamed AG). Antigen-negative crossmatch-compatible blood was transfused if the antibody was clinically significant, whereas for clinically insignificant antibodies, crossmatch-compatible blood at anti-human globulin phase was issued for transfusion.Results: The overall incidence of RBC alloimmunization in transfused patients was 3·4% (18/531), with anti-c being the most common specificity (38·8%), followed by anti-E (22·2%), anti-M (11·1%), anti-Lea (11·1%), anti-D (5·6%), anti-Jka (5·6%) and anti-Leb (5·6%). The highest incidence of alloimmunization was observed in gastroenterology patients (4·5%), followed by hematology patients (3·5%). Of the antibodies detected, 16·7% (3/18) were clinically insignificant with Lea, Leb and M specificities.Conclusions: The majority of alloantibodies detected in the current study were clinically significant. Thus, pre-transfusion antibody screening on patients' samples prior to crossmatching needs to be initiated in India to ensure safe transfusion practice.