Ali, Quratulain Zulfiqar

Abstract Objective Dravet syndrome (DS) is a developmental and epileptic encephalopathy. Diagnosis is clinical, but ~90% of patients have pathogenic variants in SCN1A . ATP6V0C has recently been proposed as a novel candidate gene for epilepsy, with or without developmental delay. Here we describe two adult patients with a clinical diagnosis of DS associated with ATP6V0C variants. Methods Patients with developmental and epileptic encephalopathies were evaluated by physicians who are experts in DS, and their clinical diagnosis was correlated with genetic findings. A subgroup of those patients with DS but without known genetic causes were evaluated through gene panels, whole exome sequencing, and chromosome microarray. Phenotype was determined by pediatric and adult chart reviews, interviews, and physical examinations. Results Of 753 patients with DS, two unrelated individuals with classic features of DS during childhood and adulthood were identified with heterozygous de novo missense variants in ATP6V0C (c.319G > C, p.(Gly107Arg) and c.284C > T, p.(Ala95Val), respectively). Both variants were absent in normal populations and computational prediction algorithms suggested deleterious effects on protein structure and/or function. No disease‐causing variants in other genes previously associated with DS were found. Significance Here we describe two adult patients with Dravet‐like syndrome and pathogenic/likely pathogenic variants in ATP6V0C . We propose that abnormal ATP6V0C function can, at the severe end of the clinical spectrum, be associated with Dravet‐like phenotype. This is relevant, as these patients would not qualify for disease‐modifying antisense nucleotide or gene therapies targeting SCN1A .

AbstractObjectiveVaccination against the SARS‐CoV‐2 virus is a primary tool to combat the COVID‐19 pandemic. However, vaccination is a common seizure trigger in individuals with Dravet syndrome (DS). Information surrounding COVID‐19 vaccine side effects in patients with DS would aid caregivers and providers in decisions for and management of COVID‐19 vaccination.MethodsA survey was emailed to the Dravet Syndrome Foundation's Family Network and posted to the Dravet Parent & Caregiver Support Group on Facebook between May and August 2021. Deidentified information obtained included demographics and vaccination status for individuals with DS. Vaccine type, side effects, preventative measures, and changes in seizure activity following COVID‐19 vaccination were recorded. For unvaccinated individuals, caregivers were asked about intent to vaccinate and reasons for their decision.ResultsOf 278 survey responses, 120 represented vaccinated individuals with DS (median age = 19.5 years), with 50% reporting no side effects from COVID‐19 vaccination. Increased seizures following COVID‐19 vaccination were reported in 16 individuals, but none had status epilepticus. Of the 158 individuals who had not received a COVID‐19 vaccination, 37 were older than 12 years (i.e., eligible at time of study), and only six of these caregivers indicated intent to seek vaccination. The remaining 121 responses were caregivers to children younger than 12 years, 60 of whom indicated they would not seek COVID‐19 vaccination when their child with DS became eligible. Reasons for vaccine hesitancy were fear of increased seizure activity and concerns about vaccine safety.SignificanceThese results indicate COVID‐19 vaccination is well tolerated by individuals with DS. One main reason for vaccine hesitancy was fear of increased seizure activity, which occurred in only 13% of vaccinated individuals, and none had status epilepticus. This study provides critical and reassuring insights for caregivers and health care providers making decisions about the safety of COVID‐19 vaccinations for individuals with DS.