Dravet Syndrome: An Overview

Abstract

Dravet syndrome (DS), also known as severe myoclonic epilepsy of infancy (SMEI), is one of the rare early childhood intractable epileptic encephalopathies associated with pleomorphic seizure activity, cognitive decline, motor, and behavioral abnormalities. The convulsive seizure is the most common type seen in DS. After the first episode of seizure-like activity, behavioral disorders and cognitive decline are progressive and long-lasting. The most common etiology identified in patients with DS is a de-novo genetic mutation alpha-1 subunit of voltage-gated calcium channel gene (SCN1A). DS is diagnosed clinically and if unclear, genetic testing is recommended. DS treatment options include anti-epileptic drugs and cannabinoids; ketogenic diet therapy and surgical options such as the deep brain and vagal nerve stimulation. Due to drug-refractory epilepsy in DS, many more therapies are being investigated to increase the longevity of patients.

A simple and effective F0 knockout method for rapid screening of behaviour and other complex phenotypes

“…To test this, we targeted scn1lab, which encodes a sodium channel. In humans, loss-of-function mutations of its ortholog SCN1A are associated with Dravet syndrome, a rare and intractable childhood epilepsy (Anwar et al, 2019). In zebrafish, scn1lab homozygous null mutants display hyperpigmentation, seizures, and complex day-night differences in free-swimming behaviour (Baraban et al, 2013;Grone et al, 2017).…”

Cannabidiol Drugs Clinical Trial Outcomes and Adverse Effects

“…The other indication awarded to GW was specific to DS, which a similar series of clinical trials were performed following preclinical research suggesting potential seizure reduction through its agonistic action on the CB1 and CB2 receptors (Anwar et al, 2019;Silvestro et al, 2019). The same titration method, dosage, and time of use was used to evaluate the safety and efficacy on patients suffering from DS; however, this study contained a smaller participant pool of 61 patients receiving the drug and 59 receiving the placebo.…”

Challenges in the Transition of Care Process for Patients with Dravet and Lennox–Gastaut Syndromes

“…1 It is a rare form of early-onset pharmacoresistant genetic epilepsy syndrome with an actual unknown frequency. 1,2 DS is considered an "epileptic encephalopathy," defined as a condition in which behavioral deterioration or regression, together with cognitive decline, is believed to be caused by epileptiform activity during brain development. 3 Two forms have been described: (1) the typical, core, SMEI, and (2) the borderline form.…”

“…1 Multiple seizure types are seen early in life, including febrile or afebrile clonic, and tonic-clonic. 1,2 Later in life, afebrile seizures are seen, mainly myoclonic seizures, followed by tonic, atypical absence, focal, and generalized seizures. Slowing of developmental and cognitive skills, and behavioral manifestation are seen over the years, with progression to severe neurologic disability and persistent motor dysfunction during adulthood.…”

“…Slowing of developmental and cognitive skills, and behavioral manifestation are seen over the years, with progression to severe neurologic disability and persistent motor dysfunction during adulthood. [1][2][3] Neurocognitive deterioration, including visual-motor integration, visual perception, and executive dysfunctions, along with language impairment, is often exaggerated once myoclonic and focal seizures start. 3 Motor system abnormalities include ataxia, tremors, dysarthria, pyramidal, and extrapyramidal signs.…”