Lennox-Gastaut syndrome: symptoms, causes and treatment

Epilepsy is a neurological disorder characterized by the appearance of episodes of abnormal electrical activity in the brain that cause seizures and mental absences, among other symptoms. It is due to alterations in the morphology or functioning of the nervous system, especially the brain.

Among the early-onset epilepsies we find the Lennox-Gastaut syndrome, characterized by frequent and heterogeneous seizures and variable intellectual disability. In this article we will describe what is Lennox-Gastaut syndrome, what are its causes and symptoms and how it is usually treated from medicine.

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What is Lennox-Gastaut syndrome?

Lennox-Gastaut syndrome is a very severe form of epilepsy that normally begins during childhood, between 2 and 6 years of age; however the symptoms may begin to occur before or after this period.

It was described in 1950 by William G. Lenox and Jean P. Davis thanks to the use of electroencephalography, which makes it possible to analyze the bioelectrical activity of the brain, detecting altered patterns such as those typical of epilepsy.

It is an infrequent disorder that accounts for only 4% of the total cases of epilepsy. It is more common in males than in females. It is resistant to treatment, although in some cases intervention may be effective. In half of the cases the disease worsens over time, while in a quarter the symptoms improve and in 20% they disappear completely.

Between 3 and 7% of children diagnosed with this syndrome die between 8 and 10 years after diagnosis, usually due to accidents: it is very common for falls to occur when seizures occur, so it is advisable to put a helmet on children with the disorder.

It is believed that there is a relationship between Lennox-Gastaut syndrome and West syndrome, also known as infantile spasms syndrome, which has similar features and includes the appearance of sudden contractions of the muscles of the arms, legs, torso and neck neck.

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Symptoms of this disorder

This syndrome is characterized by the presence of three main signs: the appearance of recurrent and varied epileptic seizures, the slowing of brain electrical activity and moderate or severe intellectual disability. It also presents with memory and learning problems, as well as motor disorders.

In half of the patients, the crises tend to be long, lasting more than 5 minutes, or they occur with little temporal separation; We know this as “status epilepticus” (status epilepsy). When these symptoms occur, the person is usually listless and dizzy, and does not respond to external stimulation.

In the Lennox-Gastaut cases psychomotor development is often impaired and delayed as a consequence of brain damage. The same happens with personality and behavior, which are influenced by epileptic problems.

common epileptic seizures

The epileptic seizures that occur in Lennox-Gastaut syndrome can be very different from each other, something that makes this disorder peculiar. The most frequent seizures are of the tonic type., which consist of periods of muscle stiffness, especially in the extremities. They usually occur at night, while the person sleeps.

Myoclonic epileptic seizures are also common, that is, those that cause spasms or sudden muscle contractions. Myoclonic seizures tend to occur more easily when the person is tired.

Tonic, atonic, tonic-clonic, partial complex, and atypical absence seizures are also relatively frequent in Lennox-Gastaut syndrome, although to a lesser extent than the previous ones. If you want to know more about the different types of epilepsy you can read this article.

Causes and factors that favor it

There are several causal factors that can explain the development of Lennox-Gastaut syndrome, although it is not possible to deduce which of them is responsible for the alteration in all cases.

Among the most frequent causes of this alteration we found the following:

• Development as a consequence of West syndrome.
• Injuries or trauma to the brain produced during pregnancy or childbirth.
• Infections in the brain, such as encephalitis, meningitis, toxoplasmosis or rubella.
• Malformations of the cerebral cortex (cortical dysplasia).
• Hereditary metabolic diseases.
• Presence of tumors in the brain due to tuberous sclerosis.
• Lack of oxygen during birth (perinatal hypoxia).

Treatment

Lennox-Gastaut syndrome is very difficult to treat: unlike most types of epilepsy, this disorder often occurs resistance to drug treatment with anticonvulsants.

Among the most widely used anticonvulsant drugs in the management of epilepsy, valproate (or valproic acid), topiramate, lamotrigine, rufinamide and felbamate stand out. Some of them can produce side effects such as viral diseases or liver toxicity.

Benzodiazepines such as clobazam and clonazepam are also administered with some frequency. However, the efficacy of any of these drugs in Lennox-Gastaut syndrome has not been definitively demonstrated.

Although until recently it was believed that surgery was not effective in treating this disorder, some recent studies and research have found that endoventricular callosotomy and vagus nerve stimulation are two promising interventions.

Likewise, in cases of epilepsy administration of a ketogenic diet is usually recommended, consisting of eating few carbohydrates and many fats. This seems to reduce the chance of having epileptic seizures; however, the ketogenic diet carries certain risks, so it must be prescribed by medical professionals.