About Lennox-Gastaut Syndrome

Lennox-Gastaut Syndrome (LGS) is the most severe form of childhood epilepsy. It is extremely rare with one retrospective study estimating the annual incidence of LGS at 0.002%. Lennox-Gastaut is characterized by daily multiple seizures of varying types, larger than that of any other epileptic syndrome. The wide range of seizure types can include tonic, myoclonic, tonic/clonic, atonic, atypical absence, and non-convulsive status seizures. 78% of children with LGS have an underlying cause such as brain lesions, genetic abnormalities, hereditary metabolic disorders, encephalitis, meningitis, brain injury, or history of infantile spasms. In 22% of the cases, no known cause can be found and this is termed “idiopathic Lennox-Gastaut”. The mortality rate of LGS ranges from 3 to 7%.

The onset of seizures usually begins between 2 and 6 years of age, with an average age of onset of 3 years. Overtime, the child will have multiple seizures that are resistant to treatment. Multiple anti-convulsant medications are usually needed to decrease the frequency of seizures, but complete seizure control is very unusual. The combination of multiple medication side effects and multiple daily seizures takes it's toll on the child and causes a progressive decline in cognitive, physical, and social development. The prognosis for these children is very poor. There is no known cure for Lennox-Gastaut syndrome and a future free of seizures and normal intellectual and/or physical development is exceedingly rare, leading many neurologists to identify LGS as a catastrophic pediatric diagnosis.