Abstracts

Variable Clinical Phenotypes and Neurological Outcomes of scn2a-related Disorders

Abstract number : 3.309
Submission category : 4. Clinical Epilepsy / 4A. Classification and Syndromes
Year : 2024
Submission ID : 427
Source : www.aesnet.org
Presentation date : 12/9/2024 12:00:00 AM
Published date :

Authors :
Presenting Author: Jong Ho Cha, MD – Seoul National University Hospital

Jaeso Cho, MD – Seoul National University Budang Hospital
Jongkeun Park, PhD – Catholic University
Seungbok Lee, MD, PhD – Seoul National University Hospital
Won Jong Choi, Mr – Catholic University
Chung Dae Sun, Mr – Catholic University
Do Young Seong, Mr – Catholic University
Dongwan Hong, PhD – Catholic University
Mi-Sun Yum, MD, PhD – Ulsan University
Jeehun lee, PhD – Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Byung Chan Lim, MD, PhD – Seoul National University Children's Hospital

Rationale: SCN2A-related disorders exhibit clinically heterogeneous expressions including epilepsy of variable onset, autism, and other neurological diseases. In this study, we aimed to describe variable clinical phenotypes of SCN2A-related disorders based on their genotypes and assess their neurological outcomes.


Methods: A multicenter retrospective review was conducted across three tertiary hospitals in Korea, focusing on patients with genetically confirmed SCN2A-related disorders. The review examined seizure onset age, responsiveness to anti-seizure medications (ASMs), and development at onset and throughout the disease. Patients were clinically classified into early onset developmental epileptic encephalopathy (DEE, seizure onset < 1 year), late onset DEE (seizure onset ≥ 1 year), self-limited familial neonatal-infantile epilepsy (SeLFNIE), and autism spectrum disorder without seizures.


Results: A total of 25 genetically confirmed SCN2A-related disease patients were enrolled in the study for review with a mean follow up of 79.4 months. Eighteen patients (72.0%) experienced seizure onset before the age of one year, with 12 having seizure onset before one month of age. Of the 18 patients with early onset seizures, 15 were classified as having early onset DEE, 2 were classified as having SeLFNIE, and 1 patient did not have follow-up information. Seizure outcome was mostly favorable in 18 patients with early seizure onset, where 12 patients (66.7%) were either seizure free or had seizure reduction by 90%, of which 8 patients showing favorable response to sodium channel blockers. Six patients (24.0%) experienced seizure onset after or equal to the age of one year, where three patients (50%) had seizures intractable to two or more ASMs. One patient was classified as autism spectrum disorder without seizures.


Conclusions: The variable phenotypes and seizure outcomes in SCN2A-related disorders necessitate a tailored treatment approach based on genotypes and seizure onset. Further tools are needed to predict the functionality of specific variants in SCN2A-related disorders.


Funding: This research was supported by the research fund from Korea Health Industry Development Institute (No. 0720241068).

Clinical Epilepsy