Evaluation and pilot testing of a multidisciplinary model of care to mainstream genomic testing for paediatric inborn errors of immunity.

Molecular diagnosis of paediatric inborn errors of immunity (IEI) influences management decisions and alters clinical outcomes, through early use of targeted and curative therapies. The increasing demand for genetic services has resulted in growing waitlists and delayed access to vital genomic testing. To address this issue, the Queensland Paediatric Immunology and Allergy Service, Australia, developed and evaluated a mainstreaming model of care to support point-of-care genomic testing for paediatric IEI. Key features of the model of care included a genetic counsellor embedded in the department, state-wide multidisciplinary team meetings, and variant prioritisation meetings to review whole exome sequencing (WES) data. Of the 62 children presented at the MDT, 43 proceeded to WES, of which nine (21%) received a confirmed molecular diagnosis. Changes to treatment and management were reported for all children with a positive result, including curative hematopoietic stem cell transplantation (n = 4). Four children were also referred for further investigations of variants of uncertain significance or additional testing due to ongoing suspicion of genetic cause after negative result. Demonstrating engagement with the model of care, 45% of the patients were from regional areas and on average, 14 healthcare providers attended the state-wide multidisciplinary team meetings. Parents demonstrated understanding of the implications of testing, reported minimal decisional regret post-test, and identified benefits to genomic testing. Overall, our program demonstrated the feasibility of a mainstreaming model of care for paediatric IEI, improved access to genomic testing, facilitated treatment decision-making, and was acceptable to parents and clinicians alike.