Mondo Description Any early infantile epileptic encephalopathy in which the cause of the disease is a mutation in the SCN1A gene.

Uniprot Description A severe form of epileptic encephalopathy characterized by generalized tonic, clonic, and tonic-clonic seizures that are initially induced by fever and begin during the first year of life. Later, patients also manifest other seizure types, including absence, myoclonic, and simple and complex partial seizures. Psychomotor development delay is observed around the second year of life. Some patients manifest a borderline disease phenotype and do not necessarily fulfill all diagnostic criteria for core EIEE6. EIEE6 is considered to be the most severe phenotype within the spectrum of generalized epilepsies with febrile seizures-plus.