Background: alloimmunization can occur in sickle cell anemia (SCA) and thalassemic patients undergoing chronic blood transfusion may lead to developing of a delayed hemolytic transfusion reaction (DHTR), which can be life-threatening condition. Our study aimed to detect the frequency of alloantibodies in chronically transfused blood in children with thalassemia and sickle cell anemia presenting in Zagazig university hospitals Patients and methods: our Comparative cross-sectional study included 190 of chronically transfused patients (thalassemia and SCA) in pediatric department, full clinical exam, lab investigations and Antibody screening and identification were carried for all participants.
Results: alloantibodies were presented by 16.3 % in thalassemic patients and by 14.7 % in SCA patients. there is statistically non-significant difference between presence of alloantibodies and gender, Rh typing, spleen status, blood groups and ABO blood groups.
Conclusion: Thalassemic and sickle cell anemic patients are at risk of alloantibodies formation and their complications
Key words: alloantibodies, thalassemia, SCA, DHTR, alloimmunization, RBCs, DHTR