Lennox-Gastaut Syndrome

Lennox-Gastaut syndrome, or LGS, is a severe form of epilepsy. Seizures usually begin in childhood. There may be periods of frequent seizures mixed with brief, relatively seizure-free periods. Most children with Lennox-Gastaut syndrome experience some degree of impaired intellectual functioning or information processing, along with developmental delays, and behavioral disturbances.

Other Names

• Myoclonic-astatic epilepsy

Types

Seizure types, which vary among patients, include:

Tonic

Seizures involve stiffening of the body, upward deviation of the eyes, dilation of the pupils, and altered respiratory patterns.

Atonic

Seizures are characterized by a brief loss of muscle tone and consciousness, causing abrupt falls.

Atypical absence

Seizures involve autonomic behavior without tonic control or staring spells.

Myoclonic

Seizures are characterized by sudden muscle jerks.

Signs and Symptoms

Common signs and symptoms of Lennox-Gastaut Syndrome include:

• Atypical absense seizures
• Tonic seizures
• Drop attacks
• Mental retardation
• Slow spike wave on EEG
• Onset before the age of five

Symptoms vary by child. Children typically have more than one type of seizure. They are also prone to develop stauts epilepticus (a continuous unrelenting seizure lasting longer than a few minutes or recurrent seizures lasting more than 30 minutes). The seizure types may change throughout a person's life. Mental retardation is commmon by the age of six.

Causes

Lennox-Gastaut syndrome can be caused by brain malformations, perinatal asphyxia (deprivation of oxygen in the newborn period), severe head injury, central nervous system infection and inherited degenerative or metabolic conditions. In about one third of cases, no cause can be found.

Diagnosis

A thorough medical history and physical examination is done, paying attention to the frequency, characteristics and age of onset of seizures.

Diagnosis is usually made after the characteristic slow spike and wave pattern is seen on electroencephalography (EEG).

Magnetic Resonance Imaging (MRI) and Computed tomography (CT) scan may also be done to evaluate the brain structure and rule out other disease.

Treatment

Medications

Treatment for Lennox-Gastaut syndrome includes anti-epileptic medications such as valproate, lamotrigine, felbamate, or topiramate. There is usually no single antiepileptic medication that will control seizures. Children who improve initially may later show tolerance to a drug or have uncontrollable seizures.

Therapies

• Stimulation of the vagus nerve has been shown to be an effective therapy for LGS. ^[1]
• Corpus callostomy (the partial or complete surgical severing of the bundle of fibers that connects the two hemispheres of the brain) has been shown to be as effective as vagus nerve stimulation in the treatment of Lennox-Gastaut syndrome. ^[2]

Holistic and alternative treatments

There has been some success using a ketotic diet^[3] to treat patients with Lennox-Gastaut syndrome. ^[4] The patients were admitted to the hospital, and given a three-day fast. A ketotic (low-carbohydrate) diet was slowly re-introduced. The frequency of seizures decreased significantly during the study period. The ketotic diet is intended for short-term use and the ketosis is reversible with glucose.

Related Problems

• Tuberous sclerosis is a rare genetic disease characterized by tumor growth on multiple organs, including the brain. It can be a cause of Lennox-Gastaut syndrome.
• Patients with West syndrome, also known as infantile spasms, may go on to develop Lennox-Gastaut syndrome. There appears to be an association between the two syndromes. ^[5]

Clinical Trials

A list of ongoing clinical trials is available here: Lennox-Gastaut trials.

Research

Recent discoveries

• Patients with Lennox-Gastaut syndrome in Africa were found to have treatment-resistant seizures with a poor prognosis. They were also noted to have facial deformities and periodontal disease. ^[6]
• Rufinamide, an anti-epilepsy drug, was shown to be a safe and effective treatmet for LGS. ^[7]

Current research

• The use of clobazam (an anti-anxiety drug) in conjunction with other antiepileptic drugs is being investigated for treatment of drop attacks. ^[8]

Expected Outcome

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 unusual.

History

Etymology

The syndrome was reportedly named for William G Lennox, an American neurologist and for Henri Gastault, a French neurologist. Both men were instrumental in the discovery and development of the EEG and the study of epilepsy.

References

1. ↑ Hosain S, Nikalov B, Harden C, Li M, Fraser R, Labar D. Vagus nerve stimulation treatment for Lennox-Gastaut syndrome. J Child Neurol. 2000 Aug;15(8):509-12. Abstract
2. ↑ You SJ, Kang HC, Ko TS, et al. Comparison of corpus callosotomy and vagus nerve stimulation in children with Lennox-Gastaut syndrome. Brain Dev. 2008 Mar;30(3):195-9. Epub 2007 Sep 6. Abstract
3. ↑ Swink TD, Vining EP, Freeman JM. The ketogenic diet: 1997. Adv Pediatr. 1997;44:297-329. Abstract
4. ↑ Freeman JM, Vining EP. Seizures decrease rapidly after fasting: preliminary studies of the ketogenic diet. Arch Pediatr Adolesc Med. 1999 Sep;153(9):946-9. Abstract | Full Text
5. ↑ Montelli TC, Iwasso MT, Peracoli MT, Mota NG. Cell-mediated and humoral immunity in West syndrome. Arq Neuropsiquiatr. 1981 Mar;39(1):1-12. Abstract
6. ↑ Abu Saleh T, Stephen L. Lennox gastaut syndrome, review of the literature and a case report. Head Face Med. 2008 Jun 9;4:9. Abstract | Full Text
7. ↑ Glauser T, Kluger G, Sachdeo R, Krauss G, Perdomo C, Arroyo S. Rufinamide for generalized seizures associated with Lennox-Gastaut syndrome. Neurology. 2008 May 20;70(21):1950-8. Epub 2008 Apr 9. Abstract
8. ↑ ClinicalTrials.gov. Clobazam in Subjects With Lennox-Gastaut Syndrome

External Links

Epilepsy Foundation: Lennox-Gastaut Syndrome

International League Against Epilepsy