Implementation of BSH 2020 irradiation guidelines for children with DiGeorge syndrome

BACKGROUND: Transfusion-associated graft-versus-host disease (Ta-GvHD) is a rare, usually fatal complication of transfusing cellular components, prevented by irradiation. Congenital heart disease (CHD), particularly DiGeorge syndrome (del22q), may be associated with severe T-cell immunodeficiency and Ta-GvHD risk. British Society for Haematology guidelines (BSH, 2020) recommended targeted use of irradiated components for CHD based on immunological assessment; guideline adherence was unknown. OBJECTIVES: To understand UK use of irradiated components for paediatric CHD surgery and barriers to BSH guideline implementation. METHODS: An electronic survey distributed to the 11 UK paediatric cardiothoracic surgical centres (January-March 2024 inclusive). RESULTS: Of the 11 centres, 9 (82%) responded. Naïve T-cell enumeration, the BSH recommended test, was available to 8/9 (89%), but used in 4/9 (44%). 4/9 (44%) and 5/9 (56%) centres were willing to provide non-irradiated components to neonates and children >28 days of age. Of these, 1/4 (25%), 1/5 (20%), and 4/5 (80%) (for neonates, young children, and children from 2 years) required criteria additional to BSH guidelines. 8/9 (89%) centres reported ongoing barriers to guideline implementation, particularly challenges around pathway development and timely naïve T-cell enumeration. CONCLUSION: Overuse of irradiated components in surgery for patients with congenital heart disease is high: only 1/3 of paediatric cardiac centres adhered to BSH guidance. Reasons included difficulties in immunological diagnostic pathway development. Collaboration between paediatric cardiothoracic, transfusion and immunology teams is required to address this.