Dravet Syndrome (DS)

Dravet syndrome (DS) is a rare, severe type of childhood epileptic encephalopathy. The disease is characterized by frequent, prolonged seizures that are often difficult to treat. Repeated seizures contribute directly to developmental delay or regression and cognitive impairment.¹ 

Comorbidities frequently found in individuals with DS include disorders such as motor, speech, and cognitive impairment, behavioral disturbances, nutritional problems, and orthopedic conditions — many of which are experienced later, as the disease progresses.

Progressive Neurodevelopmental Impairment

Because of the refractory and recurrent nature of seizures in Dravet syndrome, progressive neurodevelopmental comorbidities, including developmental delay or regression and cognitive impairment, are common in children with DS.^2,3 Motor deficits, including hypotonia, balance problems, gait disturbances, ataxia, and fine motor skill deficits, are also common.³

Read more about DS clinical features

Behavioral Challenges 

Approximately half of individuals with DS exhibit behavioral problems and have difficulty regulating their emotions.^2,4 Behavioral challenges include aggressiveness, destructive behaviors, self-harm, agitation, withdrawal, autism, attention-deficit/hyperactivity disorder (ADHD), opposition, hoarding, preservation, obsessiveness, and difficulty with socialization.^3,4 

Speech Impairment

Language impairments, such as slurred or slowed speech, dysarthria, and difficulty constructing sentences, are common comorbidities in DS. Children who have DS with speech delay may benefit from early intervention with a speech-language pathologist.^3,5

Read more about the DS care team

Growth/Nutritional Problems

Approximately 60% of children with DS have problems with growth and nutrition. These disorders include failure to thrive, nutrient malabsorption, poor appetite, feeding difficulties, osteopenia, spinal scoliosis, and delayed growth that results in small stature or being underweight. In severe cases, clinicians may recommend feeding tube placement. Consulting with a dietitian may be helpful to manage this comorbidity.⁶

Read more about DS treatment

Dysautonomia

Dysautonomia, or difficulty regulating the autonomic nervous system, is another comorbidity of DS. Dysautonomia results in temperature dysregulation, tachycardia, low blood pressure, syncope, dizziness, decreased sweating, and issues with blood circulation and digestion.⁷ 

Chronic Infections

Infections of the ears, upper and lower respiratory system, and digestive system occur frequently in individuals with DS. Infections associated with DS are problematic because the fevers that accompany infections often trigger and exacerbate seizure activity.⁶ 

Around 40% of patients with DS experience chronic otitis and 28% experience chronic bronchitis or pneumonia.⁸ Dysautonomia complicates the problem further by interfering with the body’s ability to self-regulate internal temperature.⁷

Read more about DS risk factors

Orthopedic Conditions

Osteopenia, broken bones, spinal scoliosis, and foot and ankle deformities may develop as a result of the motor deficits caused by frequent seizures in DS.^5,6,8 Children with DS may require an orthopedic assessment to determine if surgery is needed to correct foot and ankle deformities interfering with lower-extremity alignment and mobility.⁵ 

Sleep Disturbance

Between 75% and 97% of individuals with DS experience sleep disturbances due to recurrent seizure activity at night. Daytime sleepiness, exacerbation of behavioral problems and learning impairment, and fatigue may result from poor restorative sleep, negatively affecting the quality of life of children and adults with DS.⁹ 

One sleep disturbance in individuals with DS is circadian rhythm disorder, which interferes with the sleep-wake cycle and is caused by a decrease in γ-aminobutyric acid-ergic (GABAergic) neurotransmission. Patients who have sleep disorders associated with DS may benefit from treatments that improve GABAergic transmission.¹⁰

Read more about DS experimental therapies

Sensory Integration Disorders

A small minority of children with DS may have dysfunctional sensory processing, including visual processing, as a result of repeated, frequent seizures.¹¹ Children with sensory processing disorders may require assessment and sensory integration training performed by a pediatric occupational therapist.¹²

References

1. Dravet syndrome. Epilepsy Foundation. Accessed March 14, 2023.
2. What is Dravet syndrome? Dravet Syndrome Foundation. Accessed March 14, 2023.
3. Anwar A, Saleem S, Patel UK, Arumaithurai K, Malik P. Dravet syndrome: an overview. Cureus. 2019;11(6). doi:10.7759/cureus.5006
4. Behaviours that challenge. Dravet Syndrome UK. Accessed March 14, 2023.
5. Dravet syndrome. Cleveland Clinic. Accessed March 14, 2023.
6. Growth and nutrition concerns. Dravet Syndrome UK. Accessed March 14, 2023.
7. Dysautonomia. Dravet Syndrome UK. Accessed March 14, 2023.
8. Villas N, Meskis MA, Goodliffe S. Dravet syndrome: characteristics, comorbidities, and caregiver concerns. Epilepsy Behav. 2017;74:81-86. doi:10.1016/j.yehbeh.2017.06.031
9. Sleep problems. Dravet Syndrome UK. Accessed March 14, 2023.
10. Huang CH, Hung PL, Fan PC, et al. Clinical spectrum and the comorbidities of Dravet syndrome in Taiwan and the possible molecular mechanisms. Sci Rep. 2021;11:20242. doi:10.1038/s41598-021-98517-4
11. Guzzetta F. Cognitive and behavioral characteristics of children with Dravet syndrome: an overview. Epilepsia. 2011;52(s2):35-38. doi:10.1111/j.1528-1167.2011.02999.x
12. Dravet syndrome: what is it and what can pediatric OT do? Theracare Pediatric Services. Accessed March 14, 2023.

Reviewed by Kyle Habet, MD, on 3/22/2023.

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Maria Arini Lopez, PT, DPT, CSCS, CMTPT, CIMT

Maria Arini Lopez, PT, DPT, CSCS, CMTPT, CIMT is a freelance medical writer and Doctor of Physical Therapy from Maryland. She has expertise in the therapeutic areas of orthopedics, neurology, chronic pain, gastrointestinal dysfunctions, and rare diseases especially Ehlers Danlos Syndrome.