A Case Report on SCN2A-Related Developmental and Epileptic Encephalopathy and Benign Familial Infantile Seizures

Abstract

The phenotypic spectrum of SCN2A-related epilepsy was broad, ranging from benign epilepsy in neonate and infancy to severe epileptic encephalopathy. Developmental and epileptic encephalopathy and benign familial infantile seizures are caused by heterozygous mutations in the SCN2A gene. Developmental and epileptic encephalopathy is a neurologic disorder characterized by the onset of seizures in the first days, weeks, or months of life. Seizures comprise multiple types, including tonic, generalized, and myoclonic, and tend to be refractory to medication. Additional common features include microcephaly, hypotonia, and abnormal movements, such as dystonia, dyskinesias, and chore athetotic movements. The phenotype is highly variable, even in patients with the same mutation. Benign familial infantile seizure is a seizure disorder of early childhood with age at onset from 3 months up to 24 months. It is characterized by brief seizures beginning with a slow deviation of the head and eyes to one side and progressing to generalized motor arrest and hypotonia, apnoea and cyanosis, and limb jerks. Seizures that begin shortly after birth or in infancy and are not associated with fever may suggest an SCN2A-related disorder. Genetic testing is required to confirm a diagnosis. Treatment for SCN2A-related disorders will depend on the type and severity of the seizures. Even Sodium channel-blocking medications are more effective, a combination of seizure medications is typically used to control the different seizure types. Key words: SCN2A gene, Developmental and epileptic encephalopathy, Benign familial infantile seizures, Genetic testing.