Lennox-Gastaut syndrome is a severe form of epilepsy. Seizures begin in early childhood, usually before the age of 4 years.
Children, adolescents, and adults with Lennox-Gastaut syndrome have multiple types of seizures that vary among individuals. Common seizure types include:
- tonic seizures (stiffening of the body, upward eye gaze, dilated pupils, and altered breathing patterns)
- atypical absences (staring spells)
- atonic seizures (brief loss of muscle tone, which could cause abrupt falls)
- myoclonic seizures (sudden muscle jerks), and
- generalized tonic-clonic seizures (muscle stiffness and rhythmic jerking).
There may be periods of frequent seizures mixed with relatively seizure-free periods. Although not always present at the onset of seizures, most people with Lennox-Gastaut syndrome experience some degree of impaired intellectual functioning or information processing, along with developmental delays and behavioral disturbances.
A particular patten of brain electric activity can be seen using electroencephalogram (EEG). Lennox-Gastaut syndrome can be caused by a variety of conditions, including brain malformations, tuberous sclerosis, perinatal asphyxia, severe head injury, central nervous system infection, and inherited genetic and inherited degenerative or metabolic conditions. In 30-35 percent of individuals, no cause can be found.
The prognosis for individuals with Lennox-Gastaut syndrome varies. There is no cure for the disorder. Complete recovery, including freedom from seizures and normal development, is very rare.
Lennox-Gastaut syndrome can be very difficult to treat. A combination of seizure medications and other treatments may be used to improve seizure control and other associated conditions.
The medication valproate is generally considered a first-line therapy for various seizure types. Other anticonvulsant medications may include clobazam, felbamate, lamotrigine, rufinamide, topiramate, and cannabidiol.
In June 2018 the U.S. Food and Drug Administration approved cannabidiol (Epidolex, derived from marijuana) for the treatment of seizures associated with Lennox-Gastaut syndrome in individuals ages 2 and older. The drug contains only small amount of the psychoactive element in marijuana and does not induce euphoria associated with the drug.
Other treatment options include dietary therapy with the ketogenic diet, vagus nerve stimulation, and epilepsy surgery (typically a corpus callostomy, which involves severing the band of nerve fibers that connect the two halves of the brain to prevent seizures from spreading). Medication may be combined with the other treatments to optimize seizure control. Children who improve initially may later show tolerance to a drug or have uncontrollable seizures.