SCN8A encephalopathy

Disease Overview

SCN8A encephalopathy is a very rare form of early-onset epilepsy that causes multiple types of seizures and developmental delay or regression (loss of skills).[12036] Seizures begin during the first 18 months of life, at an average age of 4 months. Types of seizures may include generalized tonic-clonic seizures, infantile spasms, absence seizures, and focal seizures. Other signs and symptoms of SCN8A encephalopathy may include low muscle tone (hypotonia), a high pain tolerance, movement disorders (such as dystonia and ataxia), mild to severe intellectual disability, sleep problems, and autistic-like features.[12036][14571][12037][12038] In some people with SCN8A encephalopathy, various other medical problems have been reported including hearing or vision problems, scoliosis, and difficulty regulating body temperature. About 10% of people with SCN8A encephalopathy reported in the literature have died from sudden unexpected death in epilepsy (SUDEP).[14571]

SCN8A encephalopathy is caused by mutations in the SCN8A gene. Inheritance is autosomal dominant, but most people with SCN8A encephalopathy have a new mutation in the gene that was not inherited from a parent.[14571] Treatment aims to control seizures with medications, which is extremely challenging. Seizure control should be managed by a pediatric neurologist with expertise in epilepsy who is familiar with SCN8A encephalopathy.[14571]

Synonyms

• SCN8A epilepsy
• Early infantile epileptic encephalopathy-13
• Epileptic Encephalopathy, early infantile, 13
• EIEE13