Dravet syndrome is a rare form of epilepsy associated with neurological development disorders. The onset is during the first year of life in a normal developing child.

Dravet Syndrome was first described in 1978 as “Severe Myoclonic Epilepsy in Infancy” (SMEI) by Dr Charlotte DRAVET but has been recognized throughout the world since then.

The first description of the clinical picture was:

  • Seizures appeared before the age of one year in an otherwise normally developing infant
  • The first seizures were convulsions (clonic or tonic-clonic) associated with fever. These seizures were often long or very long (in some cases, more than one hour) and required emergency treatment (rectal or intravenous injection of an anti-convulsive drug).
  • Between the age of 2 and 3 years, other types of seizures developed (myoclonic seizuresatypical absencespartial (focal) seizures) accompanied by developmental regression or stagnation with behaviour disorders. The brain CT scan remained normal.

Because all of these clinical signs were not present in every patient, the criteria were enlarged and in 2001, the International League Against Epilepsy changed the epilepsy syndrome name from “SMEI” to “Dravet syndrome”.

The exact frequency in the general population is unknown. In 1990 it was estimated that Dravet syndrome occurred between 1/20,000 and 1/40,000 births. This frequency was probably an underestimate because the disease was not well known at that time.

Dravet syndrome seems to affect an equal number of boys and girls and no geographic region has a particularly high or low number of cases.

For references, please access “Dravet Syndrome/ Tonic-clonic seizures” though the the Bibliography part available in the resources tab