An Assessment of the Feasibility of Providing Extended Phenotype Matched Red Blood Cells for Transfusion in Patients with Sickle Cell Disease

Abstract

Red blood cell transfusion is an established treatment for patients with sickle cell disease, a group at increased risk of alloimmunisation and haemolytic transfusion reactions. Matching for blood group antigens C, c, E, e and K reduces these risks, but antibodies to other antigens remain a concern. This study assessed the feasibility of extending antigen matching to additional blood group systems.
A series of interconnected investigations informed a feasibility analysis. Objectives were to:
1. Compare red cell antigen matching protocols to British Society Haematology guidelines for pre-transfusion compatibility procedures in blood transfusion laboratories (Milkins et al.,2013).
2. Determine antibody specificity and frequency in the sickle cell population.
3. Calculate antigen frequencies in NHS Blood and Transplant donations compared with published data.
4. Model the feasibility of providing red cells matched for Duffy (Fy), Kidd (Jk) and Ss antigens using current NHSBT inventory.
Surveys confirmed current practice, while NHS Blood and Transplant donor and patient databases provided antigen and antibody frequencies for modelling supply and demand.
Compliance with current guidelines was high (95%). However, alloantibodies were common, notably anti-C (308 cases), anti-E (224), anti-e (196), and anti-D (177). Other common specificities included anti-S (274), anti-Fya (200), and anti-Jkb (193).
Targeted donor recruitment and selective testing strategies employed by NHSBT resulted in antigen frequencies that differed significantly from published values.
Feasibility modelling demonstrated that matching for patient Fya+b, Jka+b and Ss types was achievable in 84.35% of cases; excluding Fyb increased this rate to 97.06%. However, extended matching required increased use of group O red cells.
Extended matching using the current NHSBT blood inventory is theoretically possible but not yet practical without further expansion of the blood supply. Partial implementation, such as extending matching to include Fya, may be a feasible interim step while efforts to improve the blood inventory continue.

Date of Award	2 Sept 2026
Original language	English
Awarding Institution	University of Portsmouth
Supervisor	Jeremy Mills (Supervisor) & Geoff White (Supervisor)