Frequency of irregular red cell antibodies in blood donor population

Abstract

Introduction: Irregular red blood cell (RBC) antibodies may occur in blood donors and potentially can lead to transfusion reactions or decreased survival of transfused RBCs. Therefore, it is necessary to know the prevalence of alloantibodies in donors and their clinical significance. Aims and Objectives: The study was aimed to determine the prevalence of RBC alloantibodies in blood donors. Materials and Methods: ABO typing and RhD typing were performed using the fully automated immunohematology analyzer (Qwalys 3, Diagast, France). For RhD-negative samples, a “weak D” testing was also performed by tube technique using a blend (immunoglobulin M [IgM] + IgG) of anti-D antisera (Tulip Diagnostics, Goa, India). Antibody screening (3-cell panel) and identification (11-cell panel) were done by gel technique (LISS-Coombs AHG Card, Bio-Rad, Switzerland). The antibody titer was done using the tube technique. Results: During the study period, a total of 2310 donor samples were tested. Out of these, 2299 (99.56%) were male and 11 (0.44%) were female. ABO distribution was found to be maximum for blood group B (34.5%), followed by O (33.3%), A (22%), and AB (10.3%). Among the total donors, 2085 (90.3%) were RhD positive. All the RhD-negative samples were negative on “weak D” testing. Antibody screen was positive for only one sample (0.043%); the alloantibody identified was anti-M, which was reactive in anti-human globulin phase as well, and the titer was 1. It was from a male donor who had no history of transfusion. One sample (0.04%) showed autoantibody weak positive (wk+), and there was one ABO discrepancy (0.04%), which was due to weak subgroup of A. Conclusion: The prevalence of RBC alloantibodies is 0.043% (1/2310) in our donor population. As the sample size was small, larger studies are needed to determine the actual prevalence of alloantibodies in donors.