Posttransfusion Alloimmunization Following Corticosteroid Treatment

OBJECTIVE: Researchers investigated whether corticosteroid use is associated with decreased alloimmunization in adults undergoing red cell transfusions. DESIGN: This was an observational, retrospective cohort study spanning January 1, 2014, to December 31, 2024. SETTING: This study was located at a multisite academic health system along the Texas Gulf Coast. PARTICIPANTS: Patients 18 years or older with no history of alloantibodies who received red cell transfusions were included in this study. INTERVENTION: Patients received corticosteroid treatment, defined as receiving corticosteroids within 30 days preceding transfusion. OUTCOME MEASURE: Repeat antibody detection test results 28 days after transfusion determined whether an alloimmunization event occurred. RESULTS: The Wilcoxon rank-sum test for age ( P = .806), the chi-square test for sex ( P = .364) and for ethnicity ( P = .414), and Fisher exact test for race ( P = .667) revealed the population demographics were comparable between the groups. Fisher exact test revealed no significant association between treatment and alloimmunization ( P = .098; odds ratio, 0.181; 95% CI, 0.004–1.149). Comparison among classes of corticosteroids by Fisher exact test was not significant ( P = .351). An exploratory Firth’s penalized logistic regression was used because of the rarity of alloimmunization events and yielded similar, nonsignificant estimates of corticosteroid exposure across multiple models, indicating limited model performance in this sparse-data setting. CONCLUSION: Corticosteroid exposure within 30 days before transfusion was not associated with a statistically significant reduction of first-time alloimmunization. Class-based and exploratory analyses did not identify a protective effect. The low event rate and wide CIs suggest larger studies may clarify whether an association exists.