Welcome to the Rare Classroom, a new series from Patient Worthy. Rare Classroom is designed for the curious reader who wants to get informed on some of the rarest, most mysterious diseases and conditions. There are thousands of rare diseases out there, but only a very small number of them have viable treatments and regularly make the news. This series is an opportunity to learn the basics about some of the diseases that almost no one hears much about or that we otherwise haven’t been able to report on very often.
Eyes front and ears open. Class is now in session.
The rare disease that we will be learning about today is:
What is Dravet Syndrome?
- Dravet Syndrome is a severe form of epilepsy that appears during the first year of life with frequent febrile (fever-related) seizures. Later, other types of seizures typically arise including myoclonus (involuntary muscle spasms). Status epilepticus – a state of continuous seizure requiring emergency medical care – also may occur.
- It’s not fully known how many people are affected. Reports suggest that 1 in 20,000 to 1 in 40,000 people have Dravet syndrome.
- Dravet syndrome is a clinical diagnosis that was recently determined to affect approximately 1:15,700 infants born in the US.
- Usually 2 or more seizure medications are needed to treat the multiple seizure types. The ketogenic diet has been helpful in some patients with Dravet syndrome. The Vagal Nerve Stimulator may also be useful in some patients.
- Patients with Dravet syndrome face a 15-20% mortality rate due to SUDEP (Sudden Unexplained Death in Epilepsy), prolonged seizures, and seizure-related accidents such as drowning and infections.
How Do You Get It?
- Approximately 80% of those diagnosed with Dravet syndrome have an SCN1A mutation
- The most common gene mutation linked to Dravet syndrome is in a gene called SCN1A. When this gene isn’t working properly, sodium channels in the brain (which help bran cells function) do not work correctly.
- Many other gene mutations can affect sodium channels and cause Dravet syndrome too.
- These mutations are generally not inherited and appear randomly
What Are The Symptoms?
- Children with Dravet syndrome typically experience poor development of language and motor skills, hyperactivity, and difficulty relating to others.
- Other symptoms can include:
- Absence seizures
- Cutaneous photosensitivity
- EEG abnormality
- Focal clonic seizures
- Generalized myoclonic seizures
- Febrile seizures
- Focal seizures with impaired awareness/consciousness
- Cerebral atrophy
- Developmental delays
How Is It Treated?
- The goal of treatment is to minimize the number seizures and provide emergency intervention when needed
- Oral medication is often used to treat Dravet syndrome. A ketogenic diet is also recommended. Alternative treatments have shown positive results in the overall care and management of Dravet syndrome in some patients even though they have not been fully studied. These include IVIG (Intravenous Immunoglobulin Therapy), various dietary interventions, and VNS (Vagus Nerve Stimulation). Families have also reported that the use of Cannabidiol has been beneficial with both seizure management and cognition.
- Dravet syndrome is a spectrum disorder, meaning patients present with a wide range of severity and seizure types, and no two patients respond to treatment the same way.
- Medications used for Dravet syndrome include:
- Clobazam (Onfi, Frisium, Urbanyl)
- Clonazepam (Klonopin, Rivotril)
- Levetiracetam (Keppra)
- Stiripentol (Diacomit), typically used with valproic acid and clobazam
- Topiramate (Topamax)
- Valproic Acid (Depakote, Depakene, Epilim, Epival)
- Fenfluramine (Fintepla), latest approved therapy in the US and Europe
- Alternative approaches for treatment include:
- Intravenous Immunoglobulin (IVIG) Therapy
- Liquid immunoglobulin (antibodies) is taken from the blood plasma of donors who are screened to make sure they are healthy.
- The plasma is purified and given intravenously to the “patient” to help strengthen his or her immune system
- Dietary Interventions (Ketogenic diet)
- Devised as a treatment for severe seizure disorders that do not respond to conventional medication
- Comprised almost entirely of fats and proteins
- All portions must be precisely weighed and timed
- Can cause the buildup of ketone bodies in the blood and should be closely monitored
- Vagus Nerve Stimulation Therapy
- Like a “pacemaker” for the brain
- Placed under the skin or the chest wall and a wire runs from it to the vagus nerve in the neck (no part of the brain is involved in the surgery)
- The neurologist programs the strength and the timing of the impulses according to each patient’s needs.
- For all patients, the device is programmed to go on (give stimulation) for a certain period and then go off for another period and is set to give stimulation at regular intervals during the day
- Cannabidiol was officially approved by the FDA for treatment in 2018
- Intravenous Immunoglobulin (IVIG) Therapy