This type of childhood epilepsy appears during the first years of life and is difficult to treat.
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 the functioning of the nervous system, especially the brain.
Among the early-onset epilepsies, we find Lennox-Gastaut syndrome, characterized by frequent and heterogeneous seizures and variable intellectual disability. In this article we will describe what Lennox-Gastaut syndrome is, what its causes and symptoms are, and how it is usually treated in medicine.
What is Lennox-Gastaut syndrome?
Lennox-Gastaut syndrome is a very serious form of epilepsy that usually begins during childhood, between 2 and 6 years of age ; however the symptoms may begin to appear before or after this period.
It was described in 1950 by William G. Lennox and Jean P. Davis thanks to the use of electroencephalography, which allows us to analyze the bioelectric activity of the brain, detecting altered patterns such as those that are typical of epilepsy.
It is a rare disorder that accounts for only 4% of total epilepsy cases. It is more common in males than females. It is resistant to treatment, although in some cases the intervention can 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 wear a helmet children with the disorder.
It is believed that there is a relationship between Lennox-Gastaut syndrome and West syndrome, also known as infantile spasm syndrome, which has similar characteristics and includes the appearance of sudden contractions of the muscles of the arms, legs, torso And the neck.
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 has memory and learning problems, as well as motor disorders.
In half of the patients the seizures tend to be long, lasting more than 5 minutes, or occur with little time separation; we know this as “status epilepticus” (state of epilepsy). When these symptoms occur, the person is usually listless and dizzy, and does not respond to external stimulation.
In Lennox-Gastaut cases, psychomotor development is usually altered and delayed as a consequence of brain involvement. The same is true of 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 between them, something that makes this disorder peculiar. The most frequent crises are those of the tonic type, which consist of periods of muscular rigidity, especially in the extremities. They usually occur at night, while the person sleeps.
Myoclonic epileptic seizures, that is, those that cause jerks or sudden muscle contractions, are also common. Myoclonic seizures tend to occur more easily when the person is tired.
Tonic, atonic, tonic-clonic, complex partial 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 various causal factors that can explain the development of Lennox-Gastaut syndrome, although not in all cases it is possible to deduce which of them is responsible for the alteration.
Among the most frequent causes of this alteration we find the following:
- Development as a consequence of West syndrome.
- Injury or trauma to the brain 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).
Lennox-Gastaut syndrome is very difficult to treat: unlike most types of epilepsy, this disorder tends to resist drug treatment with anticonvulsants.
Valproate (or valproic acid), topiramate, lamotrigine, rufinamide, and felbamate stand out among the most widely used anticonvulsant medications in the management of epilepsy. Some of them can cause side effects such as viral diseases or liver toxicity.
Benzodiazepines such as clobazam and clonazepam are also given 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 for treating this disorder, some recent studies and research have found that endoventricular callosotomy and vagus nerve stimulation are two promising interventions.
Also, in cases of epilepsy , the administration of a ketogenic diet is usually recommended, consisting of eating few carbohydrates and many fats. This appears to reduce the likelihood of epileptic seizures; however, the ketogenic diet carries certain risks, so it should be prescribed by medical professionals.