Frequencies of and Predisposing Factors to Red Cell Alloimmunization Post Single Red Cells or Whole Blood Transfusion in a Tertiary Hospital in North Central Nigeria: A Prospective Cohort Study

Abstract

Introduction: Alloimmunized blood transfusion recipients represent genetically distinct group with increased susceptibility to red cell sensitization. Red cell sensitization depends on factors like sex, racial antigenic differences between donors and recipients amongst others. The objective of this study is to evaluate the frequencies and predisposing factors to red cell alloimmunization in this environment. Methods: Prospective cross sectional study in which 300 patients above 15 years who had one unit of red cells or whole blood transfusions for correction of anaemia were recruited. Antibody screening and identification were performed on the serum gotten after centrifuging 2ml of venous blood obtained from every patient 48 hours after transfusion using commercially prepared panel of cells. Result: Overall prevalence of alloimmunization post transfusion in this study was 4.7%. Fourteen subjects developed five types of alloantibodies: 5 (1.6%), 4 (1.3%), 2 (0.7%), 2 (0.7%) and 1 (0.3%) developed anti-K, anti-E, anti-e, anti-Le a and anti-e+anti-k respectively. Amongst the 300 blood transfusion recipients, alloimmunization was significant with age (p=0.042), female sex (p=0.031), previous transfusions (p=0.003) and group identical transfusions (p=0.033), but not with types of unit received (p=0.046). Spearman Rank-order Correlation of the five alloantibodies developed showed significant alloimmunization with sex (p=0.033), previous blood transfusions (p=0.031) and types of transfusion (p=0.024) for all the alloantibodies but not with age (p=0.120) and types of unit transfused (p=0.202). Conclusion: Because of high prevalence of alloimmunization in this study, antibody screening during pre-transfusion tests especially for multiply transfused female blood recipients is recommended for appropriate blood donor selection. Funding Information: This research was funded by Institution Based Research Fund of Nigerian Tertiary Education Trust Fund. Declaration of Interests: Authors declared no conflict of interest in this study. Ethics Approval Statement: Ethical approval was given by University of Ilorin Teaching Hospital Ethical Approval Committees with assigned number NHREC/02/05/2010. The issues of voluntariness, consent, and confidentiality were extensively discussed with every patient.