By: Natalie L. Boehm, MBA, RBLP-T
What is Dravet Syndrome?
According to the Dravet Syndrome Foundation, Dravet Syndrome, also known as Severe Myoclonic Epilepsy of Infancy (SMEI), is a rare form of retractable epilepsy that begins in infancy. Dravet Syndrome then proceeds with accumulating morbidity that significantly impacts individuals throughout their lifetime (Dravet Syndrome Foundation, 2021).
Between seventy to eighty percent of people with Dravet Syndrome have a mutation in their SCN1A gene, known as sodium channel Voltage-Gated Channel Alpha Subunit 1 (Marini et. al., 2011). The SCN1A gene is responsible for making one part (the alpha subunit) of a sodium channel called NaV1.1, which are in the brain (MedlinePlus.gov, 2017).
To diagnose Dravet Syndrome, doctors will take a blood draw and look for any mutations in the SCN1A gene. Labs may also screen SCN2A, GABRG2, AND PCDH19 mutations (CHC, 2021). Other factors such as seizure history, examination by a neurologist, and EEG testing are taken into consideration for making a diagnosis.
How Does Dravet Syndrome Affect Someone?
Dravet Syndrome can severely impact the life of not just the person, but their families as well. Individuals battling Dravet Syndrome are dependent on their family and caregivers. People with Dravet Syndrome often deal with the following:
- Prolonged Seizures
- Frequent Seizures
- Behavioral and Developmental Delays
- Movement and balance issues
- Orthopedic conditions
- Delayed language and speech issues
- Growth and nutrition issues
- Sleep difficulties
- Chronic infections
- Sensory integration disorders
- Dysautonomia, or disruptions of the autonomic nervous system which can lead to difficulty regulating body temperature, heart rate, blood pressure, and other issues.
(Dravet Syndrome Foundation, 2021)
Signs and Symptoms of Dravet Syndrome
Dravet Syndrome is often first detected between 5 to 8 months of age due to convulsions. Once on medication, the seizures can be difficult to control and can be caused by numerous triggers. Examples are infections, body temperature, flashing lights, and stress (UCSF, 2021).
The first signs of Dravet Syndrome occur when an infant has a hemiclonic seizure. Hemiclonic seizures produce jerking movement on one side of the body and may occur in clusters (CHOP, 2021). As time goes on, the person can start having different types of seizures.
A common seizure trigger for people with Dravet Syndrome is hyperthermia. Situations such as fever, exertion, increase in temperature, warm baths can all be triggers for someone with Dravet Syndrome.
Status epilepticus is common for children who have Dravet Syndrome. As they become adolescents and older adults, seizures continue but status epilepticus becomes less frequent. As a patient gets older symptoms such as speech impairment, crouched gait, hypotonia, lack of coordination, and impaired dexterity are evident (NORD, 2018).
Treatment for Dravet Syndrome
According to the University of California at San Francisco, medication is prescribed beginning with what has worked for most patients. What may work for one patient may not work for another.
Medications that are first-line treatment for patients:
Clobazam (Onfi, Frisium, Urbanyl)
Valproic acid (Depakote, Depakene, Epilim, Epival)
Topiramate (Topamax)
If first-line treatments fail, secondary medications considered are:
Stiripentol (Diacomit)
Levetiracetam (Keppra)
Medication that people with Dravet Syndrome should avoid are:
Carbamazepine (Tegretol, Carbatrol)
Oxcarbazepine (Trileptal)
Lamotrigine (Lamictal)
Phenytoin (Dilantin, Epanutin)
Vigabatrin (Sabril, Sabrilan, Sabrilex)
(UCSF, 2021)
Epidiolex, a purified form of CBD oil was approved by the FDA in 2018 for Dravet Syndrome (CHOP, 2021). The keto diet, a high-fat, low-carb diet can be successful for some patients in reducing and controlling seizure activity. A vagus nerve stimulation (VNS) can be put in when medication is not enough to control seizures. Because of the complications many with Dravet Syndrome have, physical, occupational, and speech therapy are often part of their treatment program as well.
Conclusion
Dravet Syndrome is a rare form of retractable epilepsy that begins in infancy. Along with having seizures, many with Dravet Syndrome face challenges due to behavior, developmental, and speech delays. While medication is prescribed, other treatments may be needed to control seizure activity. Many with Dravet Syndrome need support and rely on their caregivers.
Resources
Children’s Hospital Colorado (2021). Dravet Syndrome in Children. Children’s Hospital Colorado. Retrieved from: https://www.childrenscolorado.org/conditions-and-advice/conditions-and-symptoms/conditions/dravet-syndrome/
Children’s Hospital of Philadelphia (2021). Dravet Syndrome. Children’s Hospital of Philadelphia. Retrieved from: https://www.chop.edu/conditions-diseases/dravet-syndrome
Dravet Syndrome Foundation (2021). What is Dravet Syndrome? Dravet Syndrome Foundation. Retrieved from: https://www.dravetfoundation.org/what-is-dravet-syndrome/
Genetic and Rare Diseases Information Center (2021). Dravet Syndrome. National Institute of Health, Genetic and Rare Diseases Information Center. Retrieved from: https://rarediseases.info.nih.gov/diseases/10430/dravet-syndrome
Marini, C., Scheffer, I., Nabbout, R., Suls, A., De Jonghe, P., Zara, F., & Guerrini, R. (2011). The genetics of Dravet syndrome. Epilepsia (Copenhagen), 52(2), 24-29.
Medline Plus (2017). SCN1A Gene. U.S. National Library of Medicine. Retrieved from: https://medlineplus.gov/genetics/gene/scn1a/#:~:text=The%20SCN1A%20gene%20belongs%20to,instructions%20for%20making%20sodium%20channels.&text=The%20SCN1A%20gene%20provides%20instructions,of%20sodium%20ions%20into%20cells.
National Organization for Rare Disorders (2018). Dravet Syndrome. National Organization for Rare Disorders. Retrieved from: https://rarediseases.org/rare-diseases/dravet-syndrome-spectrum/#:~:text=Dravet%20syndrome%20(DS)%20is%20a,disturbances%2C%20and%20other%20health%20problems. University of California at San Francisco (2021). Pediatric Brain Center, Dravet Syndrome. Retrieved from: https://www.ucsfbenioffchildrens.org/conditions/dravet-syndrome
University of California at San Francisco (2021). Pediatric Brain Center, Dravet Syndrome. Retrieved from: https://www.ucsfbenioffchildrens.org/conditions/dravet-syndrome
