title: High frequency of autoimmunization among transfusion-dependent Tunisian thalassaemia patients.
abstract: BACKGROUND
  Limited data are available on the frequency of RBC alloimmunization and autoimmunization in transfusion-dependent Tunisian β thalassaemia patients.
  
  
  METHODS
  We analyzed the clinical and transfusion records of 130 patients (57 females and 73 males; mean age 119 months; range 12-11 months) with β thalassaemia major and who had regular blood transfusions for periods ranging from 12 to 311 months.
  
  
  RESULTS
  Of the 130 patients, ten (7.7%) developed RBC alloantibodies. The most common alloantibodies were directed against antigens in the Rh systems. Erythrocyte-autoantibodies as determined by a positive direct antiglobulin Coombs test, developed in 52(40%) patients with and without underlying RBC alloantibodies, thereby causing autoimmune haemolytic anaemia in eleven patients (21%).
  
  
  CONCLUSIONS
  Autoimmunization to erythrocyte antigens is a frequent complication in patients with β thalassaemia major. Several factors might have contributed to the high autoimmunization rate observed in this study, including non phenotypic blood exposure and alloantibody formation prior to positive Coombs test.
authors: Service d'immuno-hématologie pédiatrique, Centre National de Greffe de moelle osseuse 2, rue Djebel Lakhdar, Bab Saadoun 1006, Tunis, Tunisie. drnawelguirat@yahoo.fr
authors: N
authors: N
authors: Guirat-Dhouib
authors: M
authors: M
authors: Mezri
authors: H
authors: H
authors: Hmida
authors: F
authors: F
authors: Mellouli
authors: H
authors: H
authors: Kaabi
authors: M
authors: M
authors: Ouderni
authors: B
authors: B
authors: Zouari
authors: S
authors: S
authors: Hmida
authors: M
authors: M
authors: Bejaoui
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D006801:Humans; D007518:Isoantibodies / Q000097:blood*; D008297:Male; D017713:Platelet Transfusion; D013789:Thalassemia / Q000097:blood / Q000276:immunology* / Q000628:therapy*; D065227:Transfusion Reaction; D014416:Tunisia
chemical_list: D007518:Isoantibodies