P.074 An assessment of next-generation panel testing in epilepsy

Abstract

Background: With the now routine use of next-generation sequencing it is important to know the baseline outcomes as they relate to clinical care for pediatric epilepsy in Ontario. We sought to assess the diagnostic yield of genetic epilepsy panel testing and characterize the impact on patient care. Methods: We conducted a retrospective chart review of patients with epilepsy seen at CHEO between 2012-2020 with genetic testing. 227 patients met our inclusion criteria. Patient charts were reviewed for clinical details, co-morbidities, genetic testing results, and changes to management. Results: Diagnostic yield was 19% for multi-gene epilepsy panel testing. A further 10% received a diagnosis from additional genetic testing. The diagnostic yield was significantly higher in patients with a younger age of onset of seizures. A direct change in clinical management as a result of the molecular diagnosis was evident for 9% of patients; however, all diagnoses impacted prognosis and family counselling. Conclusions: The diagnostic yield of genetic epilepsy panel testing conducted at CHEO is comparable to other reported rates. Genetic testing resulted in clinical benefits of recurrence risk counselling, prognostic information and though a direct change in management was advised in a minority of individuals, targeted treatment recommendations will continue to increase with ongoing testing.