Seizure Semiology and Response to Treatment in a Pediatric Cohort with SCN2A Variants: A Parent Report

This is the authors' abstract. We don't add key points for this paper.

We examined seizure semiology and response to medications in 28 children (9 female, 19 male) with likely pathogenic and pathogenic SCN2A -related epilepsy. Parents reported seizure onset, seizure semiology, genetic variants, therapies used for seizures, and response to treatment. 27 children experienced defined seizures and 1 reported no seizure history. The most common initial seizures were focal or hemi-convulsions (n=8). Tonic seizures were the most common reported seizure type while febrile and atonic or drop seizures were the least common. Most patients experienced multiple seizures daily or were entirely seizure-free, with no difference based on age at seizure onset. The proportion of effective trials of the 8 most commonly reported medications ranged from 4 of 26 trials (levetiracetam) to 5 of 10 trials (valproic acid). Phenytoin was the most commonly reported effective treatment (N=4). Topiramate was reported to be the most effective treatment in combination with another treatment (N=6). We found a wide phenotypic spectrum of SCN2A -related disorders and a possible correlation between genotype and seizure onset, semiology, and treatment response. Gain-of-function mutations in early-onset SCN2A epilepsies responded well to sodium channel blockers. Further exploration of SCN2A pathogenic variants are needed to identify mediation mechanisms of action in SCN2A -related epilepsy.