Congenital tremor and myopathy secondary to novel MYBPC1 variant.

Congenital myopathy with tremor (MYOTREM) is a recently described disorder characterized by mild myopathy and a postural and intention tremor present since early infancy. MYOTREM is associated with pathogenic variants in MYBPC1 which encodes slow myosin-binding protein C, a sarcomere protein with regulatory and structural roles. Here, we describe a family with three generations of variably affected members exhibiting a novel variant in MYBPC1 (c.656 T > C, p.Leu219Pro). Among the unique features of affected family members is the persistence of tremor in sleep. We also present the first muscle magnetic resonance images for this disorder, and report muscle atrophy and fatty infiltration.

The mitochondrial tRNA MT-TW m.5537_5538insT variant presents with significant intra-familial clinical variability.

Mitochondrial disorders can present with a wide range of clinical and biochemical phenotypes. Mitochondrial DNA variants may be influenced by factors such as degree of heteroplasmy and tissue distribution. We present a four-generation family in which 10 individuals carry a pathogenic mitochondrial variant (m.5537_5538insT, MT-TW gene) with differing levels of heteroplasmy and clinical features. This genetic variant has been documented in two prior reports, both in individuals with Leigh syndrome. In the current family, three individuals have severe mitochondrial symptoms including Leigh syndrome (patient 1, 100% in blood), MELAS (patient 2, 97% heteroplasmy in muscle), and MELAS-like syndrome (patient 3, 50% heteroplasmy in blood and 100% in urine). Two individuals have mild mitochondrial symptoms (patient 4, 50% in blood and 67% in urine and patient 5, 50% heteroplasmy in blood and 30% in urine). We observe that this variant is associated with multiple mitochondrial presentations and phenotypes, including MELAS syndrome for which this variant has not previously been reported. We also demonstrate that the level of heteroplasmy of the mitochondrial DNA variant correlates with the severity of clinical presentation; however, not with the specific mitochondrial syndrome.

Tremor Presenting in Infants and Children Aged <2 Years.

Objectives: To examine the clinical features, course, and management of children at age <2 years with tremor. Methods:Retrospective chart review of all patients aged <2 years presenting to a tertiary care neurology clinic between 2005 and 2019. Descriptive and inferential statistics were used. Results: We identified 29 children with tremor presenting at age <2 years. The mean age at onset, diagnosis and follow-up was 3.22 months (SD 3.63), 6.97 months (SD 5.44), and 10.83 months (SD 5.29), respectively. Tremor was more noticeable surrounding eating, sleep, or extreme emotions. The tremor did not interfere with development or require pharmacologic treatment in any patient. At follow-up, 31% had complete resolution of their tremor with the rest being stable or improved. Patients with resolved tremor were statistically more likely to have a younger age of diagnosis (F = 3.895, P = .033), no medical history (P = .029, χ2 = 7.112), and leg tremor (P = .028, χ2 = 7.143). Conclusion: Tremor with onset at age <2 years follows a benign course, with many patients requiring no treatment and outgrowing the disorder.

Pediatric Neurology Workforce in Canada: A 5-Year Update.

BACKGROUND: In 2013, a task force was developed to discuss the future of the Canadian pediatric neurology workforce. The consensus was that there was no indication to reduce the number of training positions, but that the issue required continued surveillance. The current study provides a 5-year update on Canadian pediatric neurology workforce data. METHODS: Names, practice types, number of weekly outpatient clinics, and dates of certification of all physicians currently practicing pediatric neurology in Canada were obtained. International data were used to compute comparisons between countries. National data sets were used to provide information about the number of residency positions available and the number of Canadian graduates per year. Models for future projections were developed based on published projected population data and trends from the past decade. RESULTS: The number of pediatric neurologists practicing in Canada has increased 165% since 1994. During this period, wait times have not significantly shortened. There are regional discrepancies in access to child neurologists. The Canadian pediatric neurology workforce available to see outpatient consultations is proportionally less than that of USA. After accounting for retirements and emigrations, the number of child neurologists being added to the workforce each year is 4.9. This will result in an expected 10-year increase in Canadian pediatric neurologists from 151 to 200. CONCLUSIONS: Despite an increase in the number of Canadian child neurologists over the last two decades, we do not predict that there will be problems with underemployment over the next decade.

Les effectifs en neurologie pédiatrique au Canada : une mise à jour tenant compte des cinq dernières années.Contexte:En 2013, un comité de réflexion a été mis sur pied afin de discuter de l'avenir des effectifs canadiens en neurologie pédiatrique. Un consensus s'est alors dessiné : bien que rien n'indique qu'il faille réduire le nombre de places disponibles dans ce domaine de formation, cette question nécessite toutefois un suivi continu. La présente étude vise ainsi à offrir une mise à jour des données qui concernent ces effectifs en tenant compte des cinq dernières années.Méthodes:Les données suivantes ont été obtenues : noms des praticiens, types de pratique, nombre de consultations hebdomadaires en clinique externe et dates de certification de tous les médecins pratiquant actuellement la neurologie pédiatrique au Canada. Des données internationales ont également été utilisées pour effectuer des comparaisons entre divers pays. Des données au niveau national ont été rassemblées pour établir le nombre de places disponibles en résidence et le nombre de diplômés canadiens par année. Des modèles de projection ont aussi été élaborés en se fondant sur des projections de population déjà publiées et sur les tendances ayant marqué la décennie précédente.Résultats:Le nombre de neurologues pédiatriques qui pratiquent au Canada a augmenté de 165 % depuis 1994. Fait à noter, les temps d'attente n'ont pas été notablement raccourcis durant cette période. Il existe aussi des disparités régionales en matière d'accès à cette spécialité de la neurologie. Les effectifs canadiens en neurologie pédiatrique disponibles pour des consultations en clinique externe demeurent proportionnellement moins importants qu'aux États-Unis. Après avoir tenu compte des départs à la retraite et des apports de l'extérieur, le nombre de neurologues pédiatriques ajoutés chaque année a été en moyenne de 4,9. Pendant une période de 10 ans, on anticipe donc qu'on devrait passer de 151 à 200 neurologues pédiatriques canadiens.Conclusions:En dépit d'une hausse du nombre de neurologues pédiatriques canadiens au cours des deux dernières décennies, nous ne prédisons pas de problèmes de sous-emploi au cours de la prochaine décennie.

Prevalence and risk factors for autism spectrum disorder in epilepsy: a systematic review and meta-analysis.

AIM: To assess the prevalence and risk factors for autism spectrum disorder (ASD) in epilepsy, and to better understand the relationship and comorbidity between these disorders. METHOD: PsychINFO and PubMed were searched for articles published in the past 15 years that examined the prevalence of ASD in individuals with epilepsy. RESULTS: A total of 19 studies were found with a pooled ASD prevalence of 6.3% in epilepsy. When divided by type, the risks of ASD for general epilepsy, infantile spasms, focal seizures, and Dravet syndrome were 4.7%, 19.9%, 41.9%, and 47.4% respectively. Studies with populations under 18 years showed a 13.2 times greater risk of ASD than study populations over 18 years, and samples with most (>50%) individuals with intellectual disability showed a greater risk 4.9 times higher than study populations with a minority of individuals with intellectual disability. The main risk factors for ASD reported in the 19 studies included presence of intellectual disability, sex, age, and symptomatic aetiology of epilepsy. INTERPRETATION: Current research supports a high prevalence of ASD in epilepsy. This study helps to define the clinical profile of patients with epilepsy who are at risk for ASD, which may help clinicians in early screening and diagnosis of ASD in this population. WHAT THIS PAPER ADDS: Critical evaluation of previous studies examining the prevalence of autism spectrum disorder (ASD) in individuals with epilepsy. A meta-analysis of 19 studies showed a pooled ASD prevalence of 6.3% in individuals with epilepsy. Studies that included a majority of individuals with intellectual disability or younger population age had a higher prevalence of autism. Risk factors reported in studies included presence of intellectual disability, sex, age, and symptomatic epilepsy origin.