Abstract
INTRODUCTION: Transfusion of single-donor platelets (SDP) from O donors to non-O recipients poses a significant risk of hemolytic reactions due to high-titer anti-A and anti-B antibodies in donor plasma. These antibodies bind to A and/or B antigens on recipient red blood cells, potentially causing an immune response and hemolysis. The primary objective of this cross-sectional study is to quantify IgM and IgG anti-A and anti-B titers in 'O' blood group single donor platelets (SDP). The secondary objective is to assess the influence of donor demographic, physical, and lifestyle factors on antibody levels to guide safe transfusion practices. METHODS: A cross-sectional study was conducted on 100 group O SDP donors at a tertiary hospital from December 2022 to November 2023. Antibody titration was performed using the tube method with serial dilutions. The IgM and IgG titers were assessed by two blinded observers. Donor characteristics such as age, gender, diet, smoking, alcohol use, and BMI were recorded via questionnaire. Associations with antibody titers were analyzed. RESULTS: More donors had high anti-A IgM titers (≥64) versus anti-B IgM (43% vs. 26%, p = 0.0053). Anti-A IgG ≥128 was more common than anti-B (56% vs. 38%, p=0.002). Anti-A IgM and IgG titers remained stable across age groups, while anti-B IgM showed a weak negative correlation with age (ρ = -0.21, p = 0.04); anti-B IgG was unchanged across ages (ρ = -0.08, p = 0.42). Females had higher antibody titers than males (p<0.05). Vegetarian donors had a higher proportion of anti-A IgM levels≥64 than mixed-diet donors (56.86% vs. 28.57%, χ² = 8.10, p = 0.004). The IgG titers did not differ by diet. Lower IgM and IgG levels were found in smokers versus non-smokers (p<0.05). Alcohol consumption correlated with lower anti-A/B IgG levels (p<0.02) but not with IgM titers. Weak correlations existed between ABO antibody titers and BMI (range: r = -0.08 to 0.08, all p > 0.38). Spearman analysis showed no association between platelet yield and ABO antibody titers (anti-A IgM, anti-A IgG, anti-B IgM, anti-B IgG), with correlations near zero (ρ = -0.06, -0.05, -0.08, -0.02) and p > 0.05. CONCLUSION: Group O SDP donors show higher anti-A than anti-B antibody levels, with titers influenced by gender, diet, and lifestyle factors. Routine antibody titer assessment may help identify safer platelet units for non-identical ABO transfusions, optimizing safety and utilization in emergencies.