Population
Sickle cell disease (SCD) patients (4 studies).
Intervention
Systematic review and meta-analysis evaluating the association between human leukocyte antigen (HLA) Class II allelic polymorphisms with the possible risk of developing red blood cell (RBC) alloantibodies.
Comparison
Outcome
Three alleles: HLA-DRB1*04, HLA-DRB1*15 and HLA-DQB1*03, found to be potentially associated with an increased risk in alloantibody formation were included in the systematic review. The primary outcome measure was alloimmunization by RBC antigen exposure in SCD patients receiving multiple transfusions. The total estimate of alloimmunization of the SCD patients was 2.33 (95% CI, 1.58-3.44), demonstrating susceptibility to RBC alloantibody formation. Heterogeneity between the studies was insignificant, suggesting the differences associated with random sampling errors. The results showed that SCD patients carry an increased risk of producing RBC alloantibodies.