Epileptic Spasms-West syndrome secondary to Dravet syndrome due to SCN gene mutation from India

Abstract

Objectives: West syndrome (WS) is a triad of epileptic spasms, developmental delay/regression, and hypsarrhythmia. SCN related epileptic encephalopathy is a rare epilepsy syndrome characterized by an early-onset, severe, and epileptic encephalopathy. The causes of WS are multiple and diverse ranging from genetic to structural, metabolic, and unknown causes. The objectives of the study were to report SCN related epileptic encephalopathies with epileptic spasms. Materials and Methods: This is retrospective chart review of children presenting with epileptic spasms secondary to SCN gene variants from January 2015 to March 2020 in a tertiary care referral center. Results: Out of 15 children, ten were boys. The mean age of presentation was 5 months. Thirteen children had preceded seizures before epileptic spasms in the 1st year of life, two children presented initially with epileptic spasms. No neuro-deficits were noted in all the children. In all the cases electroencephalogram was suggestive of hypsarrhythmia. Routine testing, neuroimaging, and metabolic tests were normal in all the cases. Various pathogenic variants seen in next-generation sequencing were SCN1A in 11, SCN1B and SCN2A in two children each. Three children responded for vigabatrin and five children responded for steroids but all of them had relapse and were refractory to other antiepileptic drugs. Conclusion: SCN related epileptic encephalopathy should be considered in the differential diagnosis of epileptic spasms. These infants present earlier compare to classical Dravet syndrome children.