A Novel SCN8A mutation in a case of early-onset infantile epileptic encephalopathy: A Case Report

A Novel SCN8A mutation in a case of early-onset infantile epileptic encephalopathy: A Case Report

Authors

Keywords:

SCN8A encephalopathy, Early Infantile Epileptic Encephalopathy-13 (EIEE-13)

Abstract

SCN8A gene encodes sodium channel alpha subunit Nav1.6, and its mutation is associated with Early Infantile Epileptic Encephalopathy-13 (EIEE-13). The mean age of onset is 4-5 months.

The phenotype of SCN8A mutation varies from benign epilepsy syndromes, movement disorder, intellectual disability to severe epileptic syndromes with different types of seizures. We hereby report a case of a one-year old female who had an onset of infantile spasms on the seventeenth day of life, which gradually progressed to focal, multifocal, GTCS, and epileptic encephalopathy by one year of age associated with global developmental delay and hypotonia. All metabolic workup, TMS, GCMS, and MRI brain were normal. EEG at 2.5 months was suggestive of epileptic discharge arising from the left frontal region, evolving into generalized discharges. Whole exome sequencing revealed a heterozygous mutation in the SCN8A gene at exon 16 (p.Val892Ala) suggestive of Early Infantile Epileptic Encephalopathy-13 (EIEE-13). This is a novel mutation in the SCN8A gene which has not been reported previously in the literature.

Author Biographies

Swasti Keshri, All India Institute of Medical Sciences, Raipur

Senior Resident

Department of Paediatrics Emergency Medicine

All India Institute of Medical Sciences, Raipur

Anil Kumar Goel, All India Institute of Medical Sciences, Raipur

Professor & Head of the Department

Department of Paediatrics & Paediatrics Emergency Medicine

All India Institute of Medical Sciences, Raipur

Seema Shah, All India Institute of Medical Sciences, Raipur

Assistant Professor

Department of Biochemistry

All India Institute of Medical Sciences, Raipur

Ankit Kumar Garg, All India Institute of Medical Sciences, Raipur

Senior Resident

Department of Orthopedics

All India Institute of Medical Sciences, Raipur

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Published

21-02-2022

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Section

Case Reports: Pediatrics and Neonatology

How to Cite

1.
A Novel SCN8A mutation in a case of early-onset infantile epileptic encephalopathy: A Case Report. Acta Biomed [Internet]. 2022 Feb. 21 [cited 2024 Mar. 29];92(S1):e2021261. Available from: https://mattioli1885journals.com/index.php/actabiomedica/article/view/11781