Dravet Syndrome (aka Severe Myoclonic Epilepsy in Infancy (SMEI)) is a catastrophic epilepsy syndrome with multiple seizure types.  Afflicted children suffer a quality of life from physical and developmental regression, ataxia, sleep disturbances, orthopedic problems, and behavioral issues.

Angelina was diagnosed with Dravet Syndrome in January 2008 as having a positive SCN1A gene mutation.

The following excerpts were taken from Dr. Dravet's report on the syndrome.

Severe myoclonic epilepsy begins during the first year of life.  Development is normal prior to the onset of seizures.  Affected infants develop either generalized or unilateral clonic seizures without prodromal signs.  Myoclonic jerks and partial seizures usually appear later.  Psychomotor retardation and other neurologic deficits occur in affected children.

The seizure types for this syndrome include clonic, myoclonic, absence and complex partial.  The occurrence of status epilepticus (seizure lasting more than 30 minutes) is frequent, either convulsive (often febrile), or as obtundation status (Dravet et al 2002).  The latter consist of an impairment of consciousness, variable in intensity, the presence of fragmentary and segmental erratic myoclonias, sometimes associated with a slight increase of the muscular tone.  Convulsive seizures can either initiate or occur during or terminate these status.  Psychomotor retardation is observed usually during the second year after the onset of seizures.  Progressive neurologic deficits such as ataxia and corticospinal tract signs subsequently develop.

PROGNOSIS AND COMPLICATIONS

The outcome of Dravet is unfavorable.  The affected children will persistently be affected with seizures.  Partial seizures disappear and myoclonic jerks disappear or attenuate.  Convulsive seizures are mainly localized at the end of the night.  Fever remains a triggering factor and can still provoke epileptic status.  Neurologic abnormalities remain stable.  All patients are cognitively impaired (severely in 50%) but without deterioration after the age of 4 years (Guerrini and Dravet 1998).  Many also have behavioral disorders, including psychosis.  The mortality rate is very high, from 15.9% to 18% (Dravet et al 2002).  The cause of death is variable, including drowning, accident, seizure, status epilepticus, infection, and sudden unexpected death.

MANAGEMENT
Treatment is disappointing.  Valproate and benzodiazepines (clonazepam, lorazepam) are the most useful drugs. Phenobarbital, potassium bromide (convulsive seizures), and ethosuximide (myoclonic seizures and absences) can help some children. The effect of vigabatrin is variable. Carbamazepine and lamotrigine often have an aggravating effect (Guerrini et al 1998; Wallace 1998).  The helpfulness of Ketogenic diet needs to be proven (Caraballo et al 1998). Recently, stiripentol (Chiron et al 2000) and topiramate (Coppola et al 2002; Villeneuve et al 2002) have been shown to be effective against the convulsive seizures and the status.  It is important to avoid the long, generalized, unilateral seizures by preventing infectious diseases and hyperthermia, which are their triggering factors.

Dr. Dravet's complete report on the syndrome can be found at the following link:  Dravet's Syndrome report