Value of genetic testing for pediatric epilepsy: Driving earlier diagnosis of CLN2 Batten disease


This study assessed the effectiveness of genetic testing in shortening the time to diagnosis of late-infantile neuronal ceroid lipofuscinosis (NCL) type 2 (CLN2) disease. Individuals who received epilepsy gene panel testing through Behind the Seizure® (BTS), a sponsored genetic testing program (Cohort A), were compared to children outside of the sponsored testing program during the same period (Cohort B). Two cohorts were analyzed: children aged ≥24 to ≤60 months with unprovoked seizure onset ≥24 months between December 2016 and January 2020 (Cohort 1) and children aged 0 to ≤60 months at time of testing with unprovoked seizure onset at any age between February 2019 and January 2020 (Cohort 2). The diagnostic yield in Cohort 1A (n=1,814) was 8.4% (n=153). The TPP1 diagnostic yield within Cohort 1A was 2.9-fold higher compared to Cohort 1B (1.0%, n=18/1,814 vs 0.35%, n=8/2,303; P = 0.0157). The average time from first symptom to CLN2 disease diagnosis was significantly shorter than previously reported (9.8 vs 22.7 months, p < 0.001). These findings indicate that facilitated access to early epilepsy gene panel testing helps to increase diagnostic yield for CLN2 disease and shortens the time to diagnosis, enabling earlier intervention.