Prevalence of High Titre Alpha and Beta Haemolysins among Voluntary O Group Blood Donors in Dept. of Transfusion Medicine Govt. Medical College Trivandrum

Background:The ABO blood group system is a fundamental to safe transfusion practices. Group O blood is often called as the "universal donor" due to the absence of A and B antigens on red blood cells. the presence of high-titre anti-A and anti-B antibodies (hemagglutinins) in group O plasma can cause hemolytic transfusion reactions when transfused into non-group O recipients, especially during plasma-containing component transfusions. Objective:This study aimed to determine the prevalence of high-titre anti-A and anti-B antibodies among group O blood donors and evaluate their potential risk in non-identical ABO transfusions. Methods:A cross-sectional observational study was conducted over six months at the Department of Transfusion Medicine, Government Medical College, Trivandrum. A total of 864 voluntary group O blood donors aged 18–60 years were enrolled. Anti-A and anti-B antibody titres were determined using the standard tube titration technique. To differentiate IgM and IgG isotypes, donor plasma was treated with Dithiothreitol (DTT). Results:High-titre hemagglutinins were identified in 30.6% of donors 25.1% with high anti-A and 14.6% with high anti-B titres. Hemolysis was observed in 10.2% of anti-A, 9.4% of anti-B, and 6.8% of both. The mean titres for anti-A and anti-B were 115 and 55, respectively. Conclusion:This study highlights the importance of routinely screening group O donors for high-titre antibodies to prevent hemolytic transfusion reactions. This is especially critical in emergency transfusions and resource-limited settings where cross-matching may be constrained.