Cw alloimmunization in multitransfused thalassemic patients of North India: Prevalence and approach to transfusion

Abstract

Background and Objectives: The C Willis or Cw antigen is a low-incidence antigen of Rh system. The antibody against the Cw antigen (anti-Cw) is an IgG antibody which may occur naturally or may be immune in nature. The identification of Cw antibody is important since it has the potential to cause hemolytic disease of the newborn as well as hemolytic transfusion reaction. This study was conducted with the aim of determining the prevalence of Cw antibody in multitransfused thalassemic patients enrolled in a Regional Blood Transfusion Center (RBTC) of North India. Methods: A retrospective descriptive observational study was conducted at the Department of Immunohematology and Blood Transfusion, LHMC and Associated Hospitals. All transfusion-dependent thalassemic (TDT) patients and non-TDT (NTDT) patients enrolled in the RBTC of the hospital till December 2018 were included in the study. Antibody screening was performed in all recipients before each transfusion. The prevalence of anti-Cw was estimated. Results: A total of 567 thalassemic patients (including TDT and NTDT) were registered in RBTC, LHMC till December 2018. On pretransfusion antibody screening and identification, 3 out of 567 thalassemic patients were found to have alloimmunization against Cw antigen. The prevalence of anti-Cw in multitransfused thalassemics was 0.53%. Conclusion: The prevalence of anti-Cw is variable in different populations and it is not a very commonly reported antibody in patients with thalassemia. One should be aware of the approach to transfusion in thalassemic patients who develop Cw alloimmunization.