Lennox-Gastaut Syndrome

Lennox-Gastaut Syndrome General Information

The Lennox-Gastaut Syndrome, also commonly known under the generic medical term of childhood epileptic encephalopathy, is one of the most severe but also a very rare epilepsy syndrome encountered in children. Its incidence rate is of about 4% of all the children epilepsy cases. The onset for this condition is between 1 and 5 years of age. The syndrome in itself is characterized by the appearance of seizures, including atypical absence seizures, tonic seizures, astatic or atonic seizures. Mental retardation also occurs in patients affected by this condition. It has been noted that some patients may be normal from a developmental point of view until the moment the syndrome occurs. However, once that happens, the patient’s condition degrades dramatically, as they lose skills. By the age of 6, all the patients are already affected by mental retardation, in various degrees.

It is very common that patients affected by the Lennox-Gastaut Syndrome have several types of seizures. The drop attacks (atonic-astatic seizures) can become the most problematic; as the patient suffers repeated injuries caused by the repeated falls. Some resort to wearing protective helmets. Stiffening (tonic seizures) can occur, most likely during the sleeping hours, while on awakening the patient is likely to suffer convulsions (generalized tonic-clonic seizures). The types of seizures typically change as the patients grow older. It is common that the drop attacks cease, and are replaced by convulsion (secondarily generalized, partial or complex partial convulsions).

Lennox-Gastaut Syndrome Symptoms

While it is common that patients suffering from the Lennox-Gastaut Syndrome do not have any neurological disabilities before the onset of the syndrome, after the symptoms appear the mental condition of the patient begins to degrade. The IQ quotient of the patient suffers a decline; all the children affected by this condition are also affected by a certain degree of mental retardation. The degree of mental impairment has been noted to depend on the age at which the seizures began, the patients suffering from more severe forms being the ones that were affected by the syndrome at an earlier age. The neuropsychological symptoms may be manifested as personality disorders, mood changes and an impairment of the educational process, as well as disorders in the psychomotor development of the patient. As the patient grows older, character problems are common. The patient may have acute episodes of psychosis, or it may be a chronic state coupled with social isolation, irritability and aggressiveness. Generally the patient has a prolonged reaction time and it takes longer for him to process information. Apathy, impaired visual-motor speed, apathy and memory problems are also very common.

The Lennox-Gastaut Syndrome may provoke seizures in the patient, which may occur at any time of the day. The duration of the seizures may span from a few moments to a couple of minutes, and the types of seizures may vary largely. Tonic seizures, atypical absences, atonic seizures as well as a large number of other types have been noted. Physical symptoms may also be present in patients suffering from the Lennox-Gastaut Syndrome, most of them underlined by the damage suffered by the central nervous system. The examining health care specialist may require a general medical examination to determine any associated conditions that may affect the patient.

Lennox-Gastaut Syndrome Treatment

In the case of patients suffering from the Lennox-Gastaut Syndrome, the treatment is aimed at lowering the seizure frequency to a minimum, allowing an increase in the quality of life for the patients and their families. Also, the prescribing health care specialist should aim at obtaining the fewest adverse effects to the treatment as possible, while using as little medication as possible. The treatment of choice for most cases of Lennox-Gastaut Syndrome consists of antiepileptic medications – however it is known that a single type of therapy does not provide relief for the patient, and thus a combination of treatment methods and therapies are most commonly employed to relieve the symptoms. Medication treatment for this condition has been recently divided into three subgroups; the first group contains medication which has been proven effective by clinical experience (such medications are Benzodiazepines, such as Nitrazepam, Clonazepam and Clobazam, or Valproic Acid), while the second group relies on uncontrolled studies that deem such drugs as Zonisamide and Vigabatrin as effective. The third group of medication has shown good results in studies that were double-blind placebo-controlled, and this group contains drugs such as Topiramate, Lamotrigine and Felbamate.

It is possible that patients suffering from the Lennox-Gastaut Syndrome may require surgery to relieve some of the symptoms. There are several surgical procedures which may be applied, depending on what is the medical condition of the patient. Corpus callosotomy is a procedure typically employed to reduce drop attacks, however it does not have any effect on other types of seizure. In rare cases, this procedure may result in a relief from seizures, however it is generally believed that this procedure is rather palliative than curative. Another procedure which may be employed is the stimulation of the vagus nerve. Some studies have shown that the seizure frequency may be reduced by up to 50% within 5 years after undergoing this procedure.

In rare cases, the patient may undergo surgery to remove a localized lesion of the cortex, as this may improve the patient’s condition. Treatment for Lennox-Gastaut Syndrome also consists of maintaining a ketogenic diet, incorporating foods with a high fat ratio. In cases of epilepsy, such diets may help by reducing the seizure frequency as well as by reducing drowsiness and improving behavior. Studies have shown that ketogenic diets may have positive results in patients suffering from the Lennox-Gastaut Syndrome as well, with the best results concerning the frequency of atypical absence seizures, myoclonic and atonic seizures. Tonic-clonic seizures and secondarily generalized tonic-clonic seizures also seem to occur less often in patients which have adopted such diets. Generally, the response to the dietary therapy occurs shortly after the patient fully adopts the diet; however there are cases in which the patient’s condition only responds months later. In such cases however, it is imperative that the family of the patient is willing to adopt the same diet, and also is able to comply with the strict conditions of the diet.There are some side effects associated with the ketogenic diet, and some of them are potentially severe. These may include renal stones, significant metabolic acidosis – especially at the beginning of the diet -, dehydration, abnormal profile of the body lipid content as well as cardiac abnormalities.