Transition in epilepsy - A pilot study with patients in and outside of academic centers.

RATIONALE: Epilepsy is a complex condition and seizures are only one part of this disease. The move from pediatric to adult healthcare system proves difficult for many adolescents with epilepsy and their families. The challenges increase when patients have epilepsies associated with intellectual and/or developmental disabilities, autism spectrum disorder, and motor disorders. Knowledge and system gaps may exist between the two systems, adding to the challenges. The main goal of this study is to understand the perception of patients with epilepsy and their families who were preparing to move from pediatric to adult healthcare system or had already moved. METHODS: A survey was distributed to patients/caregivers of patients with epilepsy through patient support groups in North America and in-person through the 2019 Epilepsy Awareness Day at Disneyland. Patients were required to be 12 years or older at the time of the survey and were divided into two groups: those between 12 and 17 years and those 18 years or older. Caregivers answered on behalf of patients who were unable to respond (e.g., intellectual disability). Major components of the survey included demographics, epilepsy details, quality and access to care received in pediatric and adult years, and questions regarding transition and readiness. RESULTS: Responses were received from 58 patients/caregivers of patients with epilepsy from Canada and the United States. In group A (patients between 12 and 17 years), none of the 17-year-old patients were spoken to about transition. Patients (caregivers) with epilepsy and intellectual and/or developmental disabilities (IDD) had less time to discuss important things during the transition/transfer phase than patients with normal intelligence. Finally, there was a statistically significant difference observed in access to specialty care reported in the adult years, compared to the years in the pediatric system. In the group B (patients 18 years and older) a) 35 % still visit their family doctor for epilepsy related treatment despite the majority being on 2 or more antiseizure medications (ASMs); b) 27 % of patients in this group were still being followed by their pediatric neurologist; c) one patient received care only through visits to the emergency department; d) only 4 % felt that they received clear instructions during transfer of care such as knowing the name of the adult healthcare practitioner and/or the name of the care institution they were being transferred to. CONCLUSIONS: This study highlights the lack of appropriate transition to adult healthcare system (AHCS) amongst an unselected group of patients with epilepsy in Canada and United States. An overwhelming majority of patients followed in the community and in academy centers were simply "transferred" to an adult health practitioner, or they remained under the care of pediatricians. Finally, most patients lack access to significant social and medical support after moving to the AHCS.

Touch-screen automatisms in the digital age.

OBJECTIVE: To describe a novel set of gestural automatisms related to the use of digital screens on smartphones and tablets in patients with epilepsy. METHODS: Representative patients were selected from among those admitted to the Epilepsy Monitoring Unit at the Toronto Western Hospital between April 2016 and January 2020, and included if they exhibited automatisms clearly related to or mimicking digital device use. RESULTS: In total 5 patients were included, 4 female. All had temporal lobe epilepsy: 2 had left mesial temporal sclerosis and 3 had normal imaging. Nearly equal numbers of seizures began with right (5/9) and left (4/9) temporal onsets, with most automatisms occurring after seizure propagation to bilateral temporal involvement (6/9). Left-handed automatisms were most common (8/9). The majority of the automatisms (7/9) were perseverative on device usage prior to the seizure. CONCLUSION: Gestural automatisms appear related to the contemporary lived experience, culture, and habitual behaviour of patients with epilepsy. In the modern era, the use of smartphones and tablets are both common and habitual for many, and this case series shows that touch-screen automatisms may be added to the semiological panoply of temporal lobe seizures.

Evaluating the Current State of Epilepsy Care in the Province of Ontario.

There are numerous challenges pertaining to epilepsy care across Ontario, including Epilepsy Monitoring Unit (EMU) bed pressures, surgical access and community supports. We sampled the current clinical, community and operational state of Ontario epilepsy centres and community epilepsy agencies post COVID-19 pandemic. A 44-item survey was distributed to all 11 district and regional adult and paediatric Ontario epilepsy centres. Qualitative responses were collected from community epilepsy agencies. Results revealed ongoing gaps in epilepsy care across Ontario, with EMU bed pressures and labour shortages being limiting factors. A clinical network advising the Ontario Ministry of Health will improve access to epilepsy care.

Updated clinical practice recommendations for managing adults with 22q11.2 deletion syndrome.

This review aimed to update the clinical practice guidelines for managing adults with 22q11.2 deletion syndrome (22q11.2DS). The 22q11.2 Society recruited expert clinicians worldwide to revise the original clinical practice guidelines for adults in a stepwise process according to best practices: (1) a systematic literature search (1992-2021), (2) study selection and synthesis by clinical experts from 8 countries, covering 24 subspecialties, and (3) formulation of consensus recommendations based on the literature and further shaped by patient advocate survey results. Of 2441 22q11.2DS-relevant publications initially identified, 2344 received full-text review, with 2318 meeting inclusion criteria (clinical care relevance to 22q11.2DS) including 894 with potential relevance to adults. The evidence base remains limited. Thus multidisciplinary recommendations represent statements of current best practice for this evolving field, informed by the available literature. These recommendations provide guidance for the recognition, evaluation, surveillance, and management of the many emerging and chronic 22q11.2DS-associated multisystem morbidities relevant to adults. The recommendations also address key genetic counseling and psychosocial considerations for the increasing numbers of adults with this complex condition.

Rare Genetic Variation and Outcome of Surgery for Mesial Temporal Lobe Epilepsy.

OBJECTIVE: Genetic factors have long been debated as a cause of failure of surgery for mesial temporal lobe epilepsy (MTLE). We investigated whether rare genetic variation influences seizure outcomes of MTLE surgery. METHODS: We performed an international, multicenter, whole exome sequencing study of patients who underwent surgery for drug-resistant, unilateral MTLE with normal magnetic resonance imaging (MRI) or MRI evidence of hippocampal sclerosis and ≥2-year postsurgical follow-up. Patients with either sustained seizure freedom (favorable outcome) or ongoing uncontrolled seizures since surgery (unfavorable outcome) were included. Exomes of controls without epilepsy were also included. Gene set burden analyses were carried out to identify genes with significant enrichment of rare deleterious variants in patients compared to controls. RESULTS: Nine centers from 3 continents contributed 206 patients operated for drug-resistant unilateral MTLE, of whom 196 (149 with favorable outcome and 47 with unfavorable outcome) were included after stringent quality control. Compared to 8,718 controls, MTLE cases carried a higher burden of ultrarare missense variants in constrained genes that are intolerant to loss-of-function (LoF) variants (odds ratio [OR] = 2.6, 95% confidence interval [CI] = 1.9-3.5, p = 1.3E-09) and in genes encoding voltage-gated cation channels (OR = 2.4, 95% CI = 1.4-3.8, p = 2.7E-04). Proportions of subjects with such variants were comparable between patients with favorable outcome and those with unfavorable outcome, with no significant between-group differences. INTERPRETATION: Rare variation contributes to the genetic architecture of MTLE, but does not appear to have a major role in failure of MTLE surgery. These findings can be incorporated into presurgical decision-making and counseling. ANN NEUROL 2022.

Management of epilepsy with eyelid myoclonia: Results of an international expert consensus panel.

OBJECTIVE: There are limited data about the treatment and management of epilepsy with eyelid myoclonia (EEM). The objective of this study was to determine areas of consensus among an international panel of experts for the management of EEM (formerly known as Jeavons syndrome). METHODS: An international steering committee was convened of physicians and patients/caregivers with expertise in EEM. This committee summarized the current literature and identified an international panel of experts (comprising 25 physicians and five patients/caregivers). This panel participated in a modified Delphi process, including three rounds of surveys to determine areas of consensus for the treatment, other areas of management, and prognosis for EEM. RESULTS: There was a strong consensus for valproic acid as the first-line treatment, with levetiracetam or lamotrigine as preferable alternatives for women of childbearing age. There was a moderate consensus that ethosuximide and clobazam are also efficacious. There was a strong consensus to avoid sodium channel-blocking medications, except for lamotrigine, as they may worsen seizure control. There was consensus that seizures typically persist into adulthood, with remission occurring in <50% of patients. There was less agreement about other areas of management, including dietary therapy, lens therapy, candidacy for driving, and outcome. SIGNIFICANCE: This international expert panel identified multiple areas of consensus regarding the optimal management of EEM. These areas of consensus may inform clinical practice to improve the management of EEM. In addition, multiple areas with less agreement were identified, which highlight topics for further research.

Clinical presentation and evaluation of epilepsy with eyelid myoclonia: Results of an international expert consensus panel.

OBJECTIVE: The objective of this study was to determine areas of consensus among an international panel of experts for the clinical presentation and diagnosis of epilepsy with eyelid myoclonia (EEM; formerly known as Jeavons syndrome) to improve a timely diagnosis. METHODS: An international steering committee was convened of physicians and patients/caregivers with expertise in EEM. This committee summarized the current literature and identified an international panel of experts (comprising 25 physicians and five patients/caregivers). This international expert panel participated in a modified Delphi process, including three rounds of surveys to determine areas of consensus for the diagnosis of EEM. RESULTS: There was a strong consensus that EEM is a female predominant generalized epilepsy syndrome with onset between 3 and 12 years of age and that eyelid myoclonia must be present to make the diagnosis. There was a strong consensus that eyelid myoclonia may go unrecognized for years prior to an epilepsy diagnosis. There was consensus that generalized tonic-clonic and absence seizures are typically or occasionally seen in patients. There was a consensus that atonic or focal seizures should lead to the consideration of reclassification or alternate diagnoses. There was a strong consensus that electroencephalography is required, whereas magnetic resonance imaging is not required for diagnosis. There was a strong consensus to perform genetic testing (either epilepsy gene panel or whole exome sequencing) when one or a combination of factors was present: family history of epilepsy, intellectual disability, or drug-resistant epilepsy. SIGNIFICANCE: This international expert panel identified multiple areas of consensus regarding the presentation and evaluation of EEM. These areas of consensus may be used to inform clinical practice to shorten the time to the appropriate diagnosis.

Building the Bridge From Pediatric to Adult Neurological Care.

In this brief communication, we discuss the current landscape and unmet needs of pediatric to adult transition care in neurology. Optimizing transition care is a priority for patients, families, and providers with growing discussion in neurology. We also introduce the activities of the University of Toronto Pediatric-Adult Transition Working Group - a collaborative interdivisional and inter-subspeciality group of faculty, advanced-practice providers, trainees, and patient-family advisors pursuing collaboration with patients, families, and universities from across Canada. We envision that these efforts will result in a national neurology transition strategy that will inform designation of health authority attention and funding.

Genomic analysis of "microphenotypes" in epilepsy.

Large international consortia examining the genomic architecture of the epilepsies focus on large diagnostic subgroupings such as "all focal epilepsy" and "all genetic generalized epilepsy". In addition, phenotypic data are generally entered into these large discovery databases in a unidirectional manner at one point in time only. However, there are many smaller phenotypic subgroupings in epilepsy, many of which may have unique genomic risk factors. Such a subgrouping or "microphenotype" may be defined as an uncommon or rare phenotype that is well recognized by epileptologists and the epilepsy community, and which may or may not be formally recognized within the International League Against Epilepsy classification system. Here we examine the genetic structure of a number of such microphenotypes and report in particular on two interesting clinical phenotypes, Jeavons syndrome and pediatric status epilepticus. Although no single gene reached exome-wide statistical significance to be associated with any of the diagnostic categories, we observe enrichment of rare damaging variants in established epilepsy genes among Landau-Kleffner patients (GRIN2A) and pediatric status epilepticus patients (MECP2, SCN1A, SCN2A, SCN8A).

Adults with tuberous sclerosis complex: A distinct patient population.

OBJECTIVES: There are few data on adults living with tuberous sclerosis complex (TSC), with most studies focusing on pediatric populations. The objective of our study was to examine a large national cohort of adults with TSC, and to describe the clinical characteristics of these adults and the nature of the multidisciplinary care that they receive. METHODS: Six Canadian medical centers collaborated in this study. Data were collected using a standardized form, and descriptive statistics were used for the analyses. RESULTS: Our study included 181 adults with definite TSC (mean age = 33.6 years [SD = 13.7]). More than 40% (n = 75) had family members affected by TSC. Forty-six percent (n = 83) of individuals had intellectual disability. Nearly 30% (n = 52) of individuals reported living alone or with a partner/spouse. Seventy-six percent (n = 138) of people had epilepsy, 43% (n = 59) of whom had drug-resistant epilepsy, and 21% (n = 29) had undergone epilepsy surgery. Neuropsychiatric disease (n = 128) and renal angiomyolipomas (n = 130) were both present in approximately 70% of people. Renal imaging was performed in 75.7% (n = 137) of participants within the past 3 years. Renal and pulmonary function tests, as well as electrocardiograms, were recently performed in a minority of individuals. SIGNIFICANCE: Our cohort of adults with TSC showed that an important proportion have a milder phenotype, and are more frequently familial, as compared to children with TSC (and differing from prior reports in adult cohorts). Drug-resistant epilepsy, neuropsychiatric comorbidities, and renal angiomyolipoma are challenging factors in adults with TSC. Our participating medical centers generally followed recommended screening strategies, but there remain important gaps in care. Multidisciplinary and structured TSC care centers offering service to adults may help to improve the health of this important patient population.

COVID-19 vaccine in patients with Dravet syndrome: Observations and real-world experiences.

OBJECTIVE: Vaccination 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. METHODS: A 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. RESULTS: Of 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. SIGNIFICANCE: These 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.

NEXMIF encephalopathy: an X-linked disorder with male and female phenotypic patterns.

PURPOSE: Pathogenic variants in the X-linked gene NEXMIF (previously KIAA2022) are associated with intellectual disability (ID), autism spectrum disorder, and epilepsy. We aimed to delineate the female and male phenotypic spectrum of NEXMIF encephalopathy. METHODS: Through an international collaboration, we analyzed the phenotypes and genotypes of 87 patients with NEXMIF encephalopathy. RESULTS: Sixty-three females and 24 males (46 new patients) with NEXMIF encephalopathy were studied, with 30 novel variants. Phenotypic features included developmental delay/ID in 86/87 (99%), seizures in 71/86 (83%) and multiple comorbidities. Generalized seizures predominated including myoclonic seizures and absence seizures (both 46/70, 66%), absence with eyelid myoclonia (17/70, 24%), and atonic seizures (30/70, 43%). Males had more severe developmental impairment; females had epilepsy more frequently, and varied from unaffected to severely affected. All NEXMIF pathogenic variants led to a premature stop codon or were deleterious structural variants. Most arose de novo, although X-linked segregation occurred for both sexes. Somatic mosaicism occurred in two males and a family with suspected parental mosaicism. CONCLUSION: NEXMIF encephalopathy is an X-linked, generalized developmental and epileptic encephalopathy characterized by myoclonic-atonic epilepsy overlapping with eyelid myoclonia with absence. Some patients have developmental encephalopathy without epilepsy. Males have more severe developmental impairment. NEXMIF encephalopathy arises due to loss-of-function variants.

Blood oxygen level-dependent (BOLD) response patterns with thalamic deep brain stimulation in patients with medically refractory epilepsy.

OBJECTIVE: Anterior nucleus of thalamus (ANT) deep brain stimulation (DBS) has shown promise as a treatment for medically refractory epilepsy. To better understand the mechanism of this intervention, we used functional magnetic resonance imaging (fMRI) to map the acute blood oxygen level-dependent (BOLD) response pattern to thalamic DBS in fully implanted patients with epilepsy. METHODS: Two patients with epilepsy implanted with bilateral ANT-DBS devices underwent four fMRI acquisitions each, during which active left-sided monopolar stimulation was delivered in a 30-s DBS-ON/OFF cycling paradigm. Each fMRI acquisition featured left-sided stimulation of a different electrode contact to vary the locus of stimulation within the thalamus and to map the brain regions modulated as a function of different contact selection. To determine the extent of peri-electrode stimulation and the engagement of local structures during each fMRI acquisition, volume of tissue activated (VTA) modeling was also performed. RESULTS: Marked changes in the pattern of BOLD response were produced with thalamic stimulation, which varied with the locus of the active contact in each patient. BOLD response patterns to stimulation that directly engaged at least 5% of the anterior nuclear group by volume were characterized by changes in the bilateral putamen, thalamus, and posterior cingulate cortex, ipsilateral middle cingulate cortex and precuneus, and contralateral medial prefrontal and anterior cingulate. SIGNIFICANCE: The differential BOLD response patterns associated with varying thalamic DBS parameters provide mechanistic insights and highlight the possibilities of fMRI biomarkers of optimizing stimulation in patients with epilepsy.

Evaluating risk to people with epilepsy during the COVID-19 pandemic: Preliminary findings from the COV-E study.

The COVID-19 pandemic has caused global anguish unparalleled in recent times. As cases rise, increased pressure on health services, combined with severe disruption to people's everyday lives, can adversely affect individuals living with chronic illnesses, including people with epilepsy. Stressors related to disruption to healthcare, finances, mental well-being, relationships, schooling, physical activity, and increased isolation could increase seizures and impair epilepsy self-management. We aim to understand the impact that COVID-19 has had on the health and well-being of people with epilepsy focusing on exposure to increased risk of seizures, associated comorbidity, and mortality. We designed two online surveys with one addressing people with epilepsy directly and the second for caregivers to report on behalf of a person with epilepsy. The survey is ongoing and has yielded 463 UK-based responses by the end of September 2020. Forty percent of respondents reported health changes during the pandemic (n = 185). Respondents cited a change in seizures (19%, n = 88), mental health difficulties (34%, n = 161), and sleep disruption (26%, n = 121) as the main reasons. Thirteen percent found it difficult to take medication on time. A third had difficulty accessing medical services (n = 154), with 8% having had an appointment canceled (n = 39). Only a small proportion reported having had discussions about epilepsy-related risks, such as safety precautions (16%, n = 74); mental health (29%, n = 134); sleep (30%, n = 140); and Sudden Unexpected Death in Epilepsy (SUDEP; 15%, n = 69) in the previous 12 months. These findings suggest that people with epilepsy are currently experiencing health changes, coupled with inadequate access to services. Also, there seems to be a history of poor risk communication in the months preceding the pandemic. As the UK witnesses a second COVID-19 wave, those involved in healthcare delivery must ensure optimal care is provided for people with chronic conditions, such as epilepsy, to ensure that avoidable morbidity and mortality is prevented during the pandemic, and beyond.

Impact of the COVID-19 pandemic on people with epilepsy: Findings from the Brazilian arm of the COV-E study.

The COVID-19 pandemic has had an unprecedented impact on people and healthcare services. The disruption to chronic illnesses, such as epilepsy, may relate to several factors ranging from direct infection to secondary effects from healthcare reorganization and social distancing measures. OBJECTIVES: As part of the COVID-19 and Epilepsy (COV-E) global study, we ascertained the effects of COVID-19 on people with epilepsy in Brazil, based on their perspectives and those of their caregivers. We also evaluated the impact of COVID-19 on the care delivered to people with epilepsy by healthcare workers. METHODS: We designed separate online surveys for people with epilepsy and their caregivers. A further survey for healthcare workers contained additional assessments of changes to working patterns, productivity, and concerns for those with epilepsy under their care. The Brazilian arm of COV-E initially collected data from May to November 2020 during the country's first wave. We also examined national data to identify the Brazilian states with the highest COVID-19 incidence and related mortality. Lastly, we applied this geographic grouping to our data to explore whether local disease burden played a direct role in difficulties faced by people with epilepsy. RESULTS: Two hundred and forty-one people returned the survey, 20% were individuals with epilepsy (n = 48); 22% were caregivers (n = 53), and 58% were healthcare workers (n = 140). Just under half (43%) of people with epilepsy reported health changes during the pandemic, including worsening seizure control, with specific issues related to stress and impaired mental health. Of respondents prescribed antiseizure medication, 11% reported difficulty taking medication on time due to problems acquiring prescriptions and delayed or canceled medical appointments. Only a small proportion of respondents reported discussing significant epilepsy-related risks in the previous 12 months. Analysis of national COVID-19 data showed a higher disease burden in the states of Sao Paulo and Rio de Janeiro compared to Brazil as a whole. There were, however, no geographic differences observed in survey responses despite variability in the incidence of COVID-19. CONCLUSION: Our findings suggest that Brazilians with epilepsy have been adversely affected by COVID-19 by factors beyond infection or mortality. Mental health issues and the importance of optimal communication are critical during these difficult times. Healthcare services need to find nuanced approaches and learn from shared international experiences to provide optimal care for people with epilepsy as the direct burden of COVID-19 improves in some countries. In contrast, others face resurgent waves of the pandemic.

Global characterization of copy number variants in epilepsy patients from whole genome sequencing.

Epilepsy will affect nearly 3% of people at some point during their lifetime. Previous copy number variants (CNVs) studies of epilepsy have used array-based technology and were restricted to the detection of large or exonic events. In contrast, whole-genome sequencing (WGS) has the potential to more comprehensively profile CNVs but existing analytic methods suffer from limited accuracy. We show that this is in part due to the non-uniformity of read coverage, even after intra-sample normalization. To improve on this, we developed PopSV, an algorithm that uses multiple samples to control for technical variation and enables the robust detection of CNVs. Using WGS and PopSV, we performed a comprehensive characterization of CNVs in 198 individuals affected with epilepsy and 301 controls. For both large and small variants, we found an enrichment of rare exonic events in epilepsy patients, especially in genes with predicted loss-of-function intolerance. Notably, this genome-wide survey also revealed an enrichment of rare non-coding CNVs near previously known epilepsy genes. This enrichment was strongest for non-coding CNVs located within 100 Kbp of an epilepsy gene and in regions associated with changes in the gene expression, such as expression QTLs or DNase I hypersensitive sites. Finally, we report on 21 potentially damaging events that could be associated with known or new candidate epilepsy genes. Our results suggest that comprehensive sequence-based profiling of CNVs could help explain a larger fraction of epilepsy cases.

De Novo Mutations in PPP3CA Cause Severe Neurodevelopmental Disease with Seizures.

Exome sequencing has readily enabled the discovery of the genetic mutations responsible for a wide range of diseases. This success has been particularly remarkable in the severe epilepsies and other neurodevelopmental diseases for which rare, often de novo, mutations play a significant role in disease risk. Despite significant progress, the high genetic heterogeneity of these disorders often requires large sample sizes to identify a critical mass of individuals with disease-causing mutations in a single gene. By pooling genetic findings across multiple studies, we have identified six individuals with severe developmental delay (6/6), refractory seizures (5/6), and similar dysmorphic features (3/6), each harboring a de novo mutation in PPP3CA. PPP3CA encodes the alpha isoform of a subunit of calcineurin. Calcineurin encodes a calcium- and calmodulin-dependent serine/threonine protein phosphatase that plays a role in a wide range of biological processes, including being a key regulator of synaptic vesicle recycling at nerve terminals. Five individuals with de novo PPP3CA mutations were identified among 4,760 trio probands with neurodevelopmental diseases; this is highly unlikely to occur by chance (p = 1.2 × 10-8) given the size and mutability of the gene. Additionally, a sixth individual with a de novo mutation in PPP3CA was connected to this study through GeneMatcher. Based on these findings, we securely implicate PPP3CA in early-onset refractory epilepsy and further support the emerging role for synaptic dysregulation in epilepsy.

Starting stiripentol in adults with Dravet syndrome? Watch for ammonia and carnitine.

OBJECTIVE: Dravet syndrome (DS) is a rare cause of severe and pharmacoresistant epileptic encephalopathy. Stiripentol (STP) has a significant therapeutic benefit in the pediatric DS population. However, STP effects on adult patients have not been well studied. In our adult STP-naive DS patient population, STP initiation was associated with encephalopathy, despite decreases in valproate and clobazam dosage. Here we explored the cause and treatment of encephalopathic manifestations associated with STP in adults. METHODS: Twenty-eight patients with a confirmed clinical and genetic diagnosis of DS who attended the Adult Epilepsy Genetics Clinic were identified retrospectively. Patients who declined or discontinued STP after fewer than 3 months of use, patients who were deceased before starting STP or seizure-free when the genetic diagnosis was confirmed, and those who started STP before leaving the pediatric system (<18 years) were excluded. Levels of ammonia, carnitine, and other anti-epileptic drugs (AEDs) were observed for patients receiving STP. Patients with high ammonia levels who received carnitine supplementation were reevaluated. They were also offered an increased dosage of stiripentol if treatment with carnitine improved the encephalopathy. RESULTS: We observed hyperammonemic encephalopathy in 77% of patients treated with STP. In seven of nine patients, we observed a rate of improvement in ammonia levels of 35% (95% confidence interval [CI] 21%-49%) at a mean carnitine dose of 991 ± 286 mg/d (range 660-1320 mg/d). Five patients whose ammonia levels normalized were also offered an increase in STP dose and they were able to tolerate higher doses with improvement in side effects. Despite such adjustments, the mean maximum stiripentol dose reached was 14.89 ± 8.72 mg/kg/d, which is lower than what is typically recommended in children (50 mg/kg/d). SIGNIFICANCE: We report hyperammonemia in adult STP-naive patients who were on valproate and clobazam, despite dose reduction of the latter drugs. We also report that treatment with carnitine improved hyperammonemia, allowing the continuation of STP.

Genetics of Epileptic Networks: from Focal to Generalized Genetic Epilepsies.

PURPOSE OF REVIEW: Seizures can arise in neocortical, thalamocortical, limbic or brainstem networks. Here, we review recent genetic mechanisms implicated in focal and genetic generalized epilepsies (GGEs). RECENT FINDINGS: Pathogenic variation in GAP activity toward RAGs 1 (GATOR1) complex genes (i.e., DEPDC5, NPRL2 and NPRL3) mainly result in focal epilepsies. They are associated with high rates of sudden unexpected death in epilepsy and malformations of cortical development (MCD), where "two-hits" in GATOR1-related pathways are also found in MCDs. Large-scale sequencing studies continue to reveal new genetic risk (germline or somatic) variants, and new genes relevant to epileptic encephalopathies (EEs). Genes previously associated with EEs, including GABAA receptor genes, are now known to play a role in both common focal and GGEs in individuals without intellectual disabilities. These findings suggest that there may be a common pathophysiological mechanism in GGEs and focal epilepsies. Finally, polygenic risk scores, based on common genetic variation, offer promise in helping to differentiate between GGEs and common forms of focal epilepsies. Genetic abnormalities are a significant cause of common sporadic epilepsies, epilepsies associated with inflammatory markers, and focal epilepsies with or without MCD. Future studies using genome sequencing may provide more answers to the remaining unresolved epilepsy cases.

Seizures and movement disorders: phenomenology, diagnostic challenges and therapeutic approaches.

Seizures and movement disorders (MDs) are distinct neurological conditions presenting with abnormal movements. Despite sharing an overlap in phenomenology, these movements have different origins. In order to explore the overlaps and the narrow boundaries between these two conditions, we performed a review of the literature to explore the risk of seizures in MDs. We discussed the mimics and chameleons including MDs that look like seizure (eg, paroxysmal dyskinesia, status dystonicus) and seizures that look like MDs (eg, epilepsia partialis continua, nocturnal frontal lobe epilepsy). Additionally, we examined the therapeutic challenges as well as the anatomical and chemical pathways relevant in the interplay between epilepsy and MDs. Finally, we proposed an algorithm to guide clinicians towards the final diagnosis of conditions characterised by the co-occurrence of MDs and seizures.