Abstract

 Background and Objectives

  Blood group antigens include more than 260 antigens on the erythrocyte cell membrane, forming 24 different blood group systems. These can be categorized in 11 major systems which account for 172 of the antigens. Incompatibility of some of these antigens, especially in multiple transfused patients, results in hemolytic reactions. Although intermediate thalassemics need fewer blood transfusions than major ones, alloimmunization is more frequent in the former. This can be due to the different frequenct rates of blood group phenotypes in intermediate thalassemics as compared with healthy people.

  Materials and Methods 

  Red blood cell antigen typing was done in 39 intermediate thalassemics and 150 healthy blood donors for Rh, Kidd, MNSs, Lutheran and Duffy blood systems. K and M antigens had different frequency rates in both groups (p<0.01, p<0.0005) showing higher frequency in patients.

 Results

 Complementary studies are recommended to be performed in order to evaluate high-risk alloimmunization in intermediate thalassemias. Assessment of the frequency of other red blood cell antigens, antibody screening, and identification of alloantibodies in immunized intermediate thalassemics can be helpful in this regard.

 Conclusions

 Kantigen is very immunogenic however its prevalence rafe is high among intermediate thalassaemics, but this contradiction can not be posed as the increasing cause of alloimmune reactions in such patients. Supplemental studies including screening and detection of post-transfusion created antibody types not only help in selecting the more appropriate blood type for thalassaemics but also help in justifying increasing alloimmune reactions in thalassaemics.