Childhood epileptic encephalopathy (Lennox-Gastaut syndrome [LGS]) is a rare and debilitating form
of childhood-onset epilepsy. The syndrome is characterized by frequent seizures and multiple
seizure types, a resistance to medications or therapies, mental retardation or regression, and an
abnormal EEG with generalized slow spike-and-wave discharges. LGS constitutes between 1-4% of
pediatric epilepsies and typically appears between the second and sixth year of life.
Some of the known causes include brain injury associated with pregnancy or birth (including
asphyxia, low birth weight, and prematurity), severe brain infections (including encephalitis,
meningitis and rubella), developmental malformations of the brain, or a history of infantile spasms. In
30-35 percent of cases, no cause can be found.
Most children are typically developing normal when first diagnosed, but then begin to lose skills,
sometimes dramatically, in association with uncontrolled seizures. Young children with LGS may
exhibit behavioral issues, personality disturbances, mood instability, and slowing of psychomotor
development. Behavioral disturbances can include poor social skills and attention seeking behavior,
which can be caused by the effects of the medication, difficulty interpreting information, or the
electric disturbances in the brain. Some children with LGS are prone to develop non-convulsive
status epilepticus (a continuous seizure state that is associated with a change in the child's level of
awareness). This requires medical intervention to bring it to an end.
As children with Lennox-Gastaut syndrome grow older, the types of seizures change. In most
cases, the drop-seizures (atonic) are replaced by partial, complex partial, and secondarily
generalized convulsions. The uncontrolled seizures may become less of an issue as children grow,
but impaired intellectual functioning and behavioral problems persist. Older children with LGS
experience acute psychotic episodes, forms of psychosis with aggressiveness, character problems,
and irritability. Cognitive problems include slowed reaction time and information processing. The
main characteristics of mental deterioration are reported as apathy, memory disorders, impaired
visuomotor speed, and perseverance.
School-age children are usually placed into a special education classroom or will receive home
tutoring. Parents and caregivers may need to consider future options for their child, including legal
guardianship, respite care, group home facilities, and/or day programs. For those individuals with
LGS who do not have adequate neurological services in their state of residency, an out-of-state
facility is suggested. Level 4 facilities (facilities which provide intensive neurological services,
elaborate evaluations and treatment options) are typically recommended if the local neurologist or
epileptologist does not have experience in treating Lennox-Gastaut syndrome.
The prognosis of Lennox-Gastaut syndrome can greatly vary from person to person. Complete
recovery, with freedom of seizures and normal development, is very unusual for a child with LGS.
Although there is no cure, there is an array of treatment options available including the ketogenic
diet, vagus nerve stimulation therapy, surgery, and anti-epiletic drugs (AED's).
For in-depth vocabulary pertaining to LGS, please click here.
This information provided by the LGS Foundation is designed to provide basic information. It is not intended, nor does it
constitute medical or other professional advice. Diagnosis and advice on LGS should be sought from a medical
professional.
of childhood-onset epilepsy. The syndrome is characterized by frequent seizures and multiple
seizure types, a resistance to medications or therapies, mental retardation or regression, and an
abnormal EEG with generalized slow spike-and-wave discharges. LGS constitutes between 1-4% of
pediatric epilepsies and typically appears between the second and sixth year of life.
Some of the known causes include brain injury associated with pregnancy or birth (including
asphyxia, low birth weight, and prematurity), severe brain infections (including encephalitis,
meningitis and rubella), developmental malformations of the brain, or a history of infantile spasms. In
30-35 percent of cases, no cause can be found.
Most children are typically developing normal when first diagnosed, but then begin to lose skills,
sometimes dramatically, in association with uncontrolled seizures. Young children with LGS may
exhibit behavioral issues, personality disturbances, mood instability, and slowing of psychomotor
development. Behavioral disturbances can include poor social skills and attention seeking behavior,
which can be caused by the effects of the medication, difficulty interpreting information, or the
electric disturbances in the brain. Some children with LGS are prone to develop non-convulsive
status epilepticus (a continuous seizure state that is associated with a change in the child's level of
awareness). This requires medical intervention to bring it to an end.
As children with Lennox-Gastaut syndrome grow older, the types of seizures change. In most
cases, the drop-seizures (atonic) are replaced by partial, complex partial, and secondarily
generalized convulsions. The uncontrolled seizures may become less of an issue as children grow,
but impaired intellectual functioning and behavioral problems persist. Older children with LGS
experience acute psychotic episodes, forms of psychosis with aggressiveness, character problems,
and irritability. Cognitive problems include slowed reaction time and information processing. The
main characteristics of mental deterioration are reported as apathy, memory disorders, impaired
visuomotor speed, and perseverance.
School-age children are usually placed into a special education classroom or will receive home
tutoring. Parents and caregivers may need to consider future options for their child, including legal
guardianship, respite care, group home facilities, and/or day programs. For those individuals with
LGS who do not have adequate neurological services in their state of residency, an out-of-state
facility is suggested. Level 4 facilities (facilities which provide intensive neurological services,
elaborate evaluations and treatment options) are typically recommended if the local neurologist or
epileptologist does not have experience in treating Lennox-Gastaut syndrome.
The prognosis of Lennox-Gastaut syndrome can greatly vary from person to person. Complete
recovery, with freedom of seizures and normal development, is very unusual for a child with LGS.
Although there is no cure, there is an array of treatment options available including the ketogenic
diet, vagus nerve stimulation therapy, surgery, and anti-epiletic drugs (AED's).
For in-depth vocabulary pertaining to LGS, please click here.
This information provided by the LGS Foundation is designed to provide basic information. It is not intended, nor does it
constitute medical or other professional advice. Diagnosis and advice on LGS should be sought from a medical
professional.
Copyright LGS Foundation, Inc., 2009