[Prevalence of alloimmunization against RBC antigens in thalassemia major patients of Lorestan province in 1383]

ABSTRACT

Thalassemia major patients should continuously receive blood to survive. Permanent blood injection will expose patients' immune system to a broad spectrum of new antigens located on the surface of injected RBCs. Continuous exposure to foreign antigens may provoke antibody production against them in the patients who lack those Ags. This phenomenon is termed alloimmunization and can cause problems for preparation of compatible blood for transfusion. 65 patients were studied in this research. At first, questionnaires eliciting information about age, race, date of blood injection, splenectomy, presence of any underlying diseases, and any certain drugs[in patients' records] were filled out by all patients. For alloantibody screening, patients' serum samples were tested by the panels prepared in IBTO. Phenotypes of RBCs for Ags of ABH and Rh[D, C, E, c, e] were also determined by relevant antisera. Out of 65 patients, only one case [1.53%] had been allommunized. The age range of males and females were 13 +/- 6 and 13 +/- 5 respectively. All of the patients were of Lurish race. The first blood transfusion in all of them occurred at the age below 3. Seventeen subjects were splenectomized. The reasons for low prevalence of alloimmunization against RBCs in thalassemia major patients may pertain to similarity of patients and donors by descent, blood transfusion before the age 3, and splenectomy in a few patients. Identification of alloantibodies by using the panel cells was the best method to provide patients with antigen negative and compatible blood for transfusion