Mutation in the SCN9A Gene Associated with Dravet Syndrome: A Pediatric Case Report

Introduction: Dravet syndrome, also known as severe myoclonic epilepsy in infancy, is a drug resistant epileptic encephalopathy that usually begins in the first year of life. It is characterized by the presence of epileptic seizures that usually have multiple triggers; the most currently associated is the presence of previous febrile episodes. It is considered as a rare disease due to its low incidence and prevalence. Case presentation: We reported the case of a ten-year-old boy with structural epilepsy associated with a neurodevelopmental delay and minor craniofacial anomalies. He had a history of uncorrected congenital heart disease, colpocephaly, and agenesis of the corpus callosum. Due to the persistence of seizures secondary to drug resistance, it was decided to perform a genetic exome that evidenced a mutation of the SCN9A gene. Conclusions: Dravet syndrome should be suspected in all patients under one year of age who have recurrent seizures associated with fever that does not respond to medication and modifies its presentation. Approximately 70%−85% of the patients diagnosed with Dravet syndrome have a mutation in the SCN1A gene; therefore, mutations in other genes that encode sodium channels located on the same chromosome, such as SCN9A, could contribute in a multifactorial way.