Dravet Syndrome
Dravet syndrome is a severe form of epilepsy characterized by frequent, prolonged seizures often triggered by high body temperature (hyperthermia), developmental delay, speech impairment, ataxia, hypotonia, sleep disturbances, and other health problems.
What is the life expectancy of a child with Dravet syndrome?
The average life expectancy of people with Dravet syndrome is not clear, but estimates suggest that 10-20% of individuals with a sudden unexpected death in epilepsy is the most common cause.
Dravet syndrome, previously known as severe myoclonic epilepsy in infancy, is a rare form of epilepsy that begins in the first year of life.
Estimates suggest it affects around 1 in 40,000 trusted source infants in the united states, though some studies indicate its true incidence may be closer to 1 in 15,000.
As well as seizures, common symptoms include mobility, behavioral, and cognitive abnormalities that develop as the child gets older.
While there is no cure for Dravet syndrome, early diagnosis and treatment may minimize seizure frequency and intensity. Without treatment, individuals will continue to have frequent seizures and can suffer from seizure-related accidents or even mortality.
Keep reading to learn more about Dravet syndrome, including the causes, symptoms, and treatment options for the condition.
Causes:
The cause of Dravet syndrome is a gene mutation. Dravet syndrome most often results from a do Novo variation, a genetic mutation not present in a child's parents. It typically develops for the first in the egg, sperm, or early embryo.
In 70-80% of individuals with Dravet syndrome, the mutation is in the SCN1A gene, which provides instructions for creating sodium channels found primarily in the brain. These channels control the flow of sodium ions and affect communication between nerve cells or neurons.
Researches suggest that SCN1A gene mutations may result in trusted source uncontrolled firing from gamma-aminobutyric acid functions as the primary inhibitory neurotransmitter for the central nervous system. Dravet syndrome appears to affect males twice as often as it affects females.
Symptoms:
Symptoms of Dravet syndrome vary by person and often change as the individual gets older. The three most commonly associated symptoms with this condition are seizures, developmental delays, and behavioral abnormalities.
Seizures:
Most individuals with Dravet syndrome start to have seizures at the age of 5-8 months trusted sources. The first seizure usually results from a trigger like a fever, but sometimes there is no trigger.
When a fever triggers a seizure, this is called a febrile seizure. Many infants have febrile seizures, and these symptoms alone don't mean a baby has Dravet syndrome.
Individuals with Dravet syndrome typically also develop other types of seizures, including:
- Focal seizures which occur in one area of the brain
- Myoclonic seizure, which causes the upper body or legs to jerk of twitch
- Atypical absence seizures which cause lapses of consciousness that can last for 20 seconds or longer
- Tonic-clonic seizures make the whole body twitch and jerk and cause a person to become unconscious.
Individuals with Dravet syndrome can get a seizure when they experience stress, and excitement, see flashing lights or have a rapid change in body temperature.
Developmental delay:
Parents typically begin to notice cognitive delays or difficulty learning and talking in infants with Dravet syndrome at 1-2 years. It can take these infants longer to reach certain milestones compared with other children.
Hypotonia, a lack of muscle tone, is common in individuals with Dravet syndrome at around 1 year old. Parents may also notice signs of ataxia, a disorder that affects coordination and balance when infants start walking.
Behavioral disturbances:
The behavioral traits associated with Dravet syndrome relate to autism, attention deficit hyperactivity disorder, irritability, and aggression.
Diagnosis:
Dravet syndrome is rare and can be challenging for doctors to diagnose. According to the international league against epilepsy trusted source, a doctor generally uses the following characteristics of the trusted sources to make a diagnosis:
- A family history of seizures or febrile seizures
- Normal developmental before the onset of seizures
- A seizure during the first year of life, followed by an increasing number of various seizures types
- An EEG test with generalized spike and polyspike waves
- Focal abnormalities or early photosensitivity
- Psychomotor delays after the age of 24 months
- Ataxia
Doctors typically recommend genetic testing in individuals likely to have Dravet syndrome.
Diet:
Research suggests that Ketogenic which is high in fat and low in carbohydrates, may help individuals with Dravet syndrome, the diet affects biochemical pathways involved in the functioning of the central nervous system. It also affects GABA levels.
Avoiding triggers:
Avoiding seizure triggers is important for people with Dravet syndrome. Hot baths, Jacuzzis, and flashing lights can all bring on seizures.
