Dravet syndrome

Dravet syndrome (or severe myoclonic epilepsy in infancy or childhood), described by the French neurologist and psychiatrist Charlotte Dravet in 1978, is a type of.

What is Dravet syndrome?

It is a refractory epileptic encephalopathy that occurs in the first years of life, more frequently in boys than in girls (in a ratio of 2 to 1). It is a disease that is classified as rare due to the small number of patients it affects.

How is it produced?

A quarter of the patients who suffer from it have a family history of any type or of seizures triggered by febrile processes. In two out of every three patients, it has been seen that there is an involvement of a gene called SCN1A, which is located on chromosome 2. In general, they are mutations that appear spontaneously, without existing in the parents of the patients.

Symptoms

Patients with Dravet syndrome present seizures during the first year of life that are usually triggered by febrile processes with high temperatures, above 39ºC. These are generalized, unilateral clonic or tonic-clonic seizures that occur approximately every one to two months.

From the second or third year of life, the seizures can be of a different nature, especially myoclonic and absence seizures (seizures in which the patient seems to disconnect from the environment that surrounds them for a few moments). At this stage of the disease, attacks last less but occur more frequently. On occasions, the seizures can lead to status epilepticus, to seizures that last more than 20 minutes or to link two seizures in a row without regaining consciousness between them, which can cause irreversible neurological damage.

With the increase in the frequency of seizures there is a slowing down of psychomotor development, conduct disorders, ataxia, symptoms similar to that of some symptoms of and growth problems. Some of these children have also been shown to suffer from photosensitivity.

Diagnosis of severe myoclonic epilepsy

The diagnosis is essentially clinical, not genetic, and is established by the presence of the characteristic seizures. An (EEG) is performed that can present significant alterations, especially from the second or third year, since during the first the EEG recording may be normal. Other imaging tests such as one may be done to rule out structural brain disease.

Treatment

Dravet syndrome does not usually have a very good response to drug treatment with anticonvulsants. The best treatment options are valproate and benzodiazepines such as clobazam. Another antiepileptic drug that has been used is stiripentol, and the use of topiramate for the treatment of seizures of severe myoclonic epilepsy in childhood is currently under study.

Treatment with other common antiepileptic drugs such as gabapentin and vigabatrin should be avoided, as they can worsen symptoms. The long-term prognosis of these patients is not very promising. Over time the frequency of seizures decreases but they may have caused damage that leads to cognitive decline and conduct disorders. Also, these patients are at increased risk of sudden death.

Precautionary measures

As it is a disease that is usually due to a genetic mutation, there are no preventive measures against it. If there is a family history of epilepsy or of it is important to monitor fever in babies and prevent it from rising with the use of apyretics such as paracetamol or ibuprofen. In the event of seizures, it is important to put yourself in the hands of a specialist, pediatrician or neurologist as soon as possible.

• It is a rare disease, due to a genetic mutation, which occurs in the first years of life, more frequently in boys than in girls.
• The absence seizure (the patient seems to disconnect from the environment that surrounds them) is one of the symptoms of Dravet Syndrome and can lead to an epileptic seizure.
• Over time the frequency of seizures decreases but these may have already caused irreversible damage such as cognitive impairment, conduct disorders and slowing of psychomotor development, among others.