The majority of epilepsies are focal in origin, with seizures emanating from one brain region. Although focal epilepsies often arise from structural brain lesions, many affected individuals have ...normal brain imaging. The etiology is unknown in the majority of individuals, although genetic factors are increasingly recognized. Autosomal dominant familial focal epilepsy with variable foci (FFEVF) is notable because family members have seizures originating from different cortical regions. Using exome sequencing, we detected DEPDC5 mutations in two affected families. We subsequently identified mutations in five of six additional published large families with FFEVF. Study of families with focal epilepsy that were too small for conventional clinical diagnosis with FFEVF identified DEPDC5 mutations in approximately 12% of families (10/82). This high frequency establishes DEPDC5 mutations as a common cause of familial focal epilepsies. Shared homology with G protein signaling molecules and localization in human neurons suggest a role of DEPDC5 in neuronal signal transduction.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Marked by incomplete division of the embryonic forebrain, holoprosencephaly is one of the most common human developmental disorders. Despite decades of phenotype-driven research, 80-90% of ...aneuploidy-negative holoprosencephaly individuals with a probable genetic aetiology do not have a genetic diagnosis. Here we report holoprosencephaly associated with variants in the two X-linked cohesin complex genes, STAG2 and SMC1A, with loss-of-function variants in 10 individuals and a missense variant in one. Additionally, we report four individuals with variants in the cohesin complex genes that are not X-linked, SMC3 and RAD21. Using whole mount in situ hybridization, we show that STAG2 and SMC1A are expressed in the prosencephalic neural folds during primary neurulation in the mouse, consistent with forebrain morphogenesis and holoprosencephaly pathogenesis. Finally, we found that shRNA knockdown of STAG2 and SMC1A causes aberrant expression of HPE-associated genes ZIC2, GLI2, SMAD3 and FGFR1 in human neural stem cells. These findings show the cohesin complex as an important regulator of median forebrain development and X-linked inheritance patterns in holoprosencephaly.
Strehlow et al. describe the largest cohort to date of individuals with GRIN2A-related disorders. The results reveal two phenotypic subgroups associated with different classes of variants affecting ...distinct domains of the GluN2A protein with different functional consequences. The findings will help predict outcomes in newly diagnosed individuals.
Abstract
Alterations of the N-methyl-d-aspartate receptor (NMDAR) subunit GluN2A, encoded by GRIN2A, have been associated with a spectrum of neurodevelopmental disorders with prominent speech-related features, and epilepsy. We performed a comprehensive assessment of phenotypes with a standardized questionnaire in 92 previously unreported individuals with GRIN2A-related disorders. Applying the criteria of the American College of Medical Genetics and Genomics to all published variants yielded 156 additional cases with pathogenic or likely pathogenic variants in GRIN2A, resulting in a total of 248 individuals. The phenotypic spectrum ranged from normal or near-normal development with mild epilepsy and speech delay/apraxia to severe developmental and epileptic encephalopathy, often within the epilepsy-aphasia spectrum. We found that pathogenic missense variants in transmembrane and linker domains (misTMD+Linker) were associated with severe developmental phenotypes, whereas missense variants within amino terminal or ligand-binding domains (misATD+LBD) and null variants led to less severe developmental phenotypes, which we confirmed in a discovery (P = 10−6) as well as validation cohort (P = 0.0003). Other phenotypes such as MRI abnormalities and epilepsy types were also significantly different between the two groups. Notably, this was paralleled by electrophysiology data, where misTMD+Linker predominantly led to NMDAR gain-of-function, while misATD+LBD exclusively caused NMDAR loss-of-function. With respect to null variants, we show that Grin2a+/− cortical rat neurons also had reduced NMDAR function and there was no evidence of previously postulated compensatory overexpression of GluN2B. We demonstrate that null variants and misATD+LBD of GRIN2A do not only share the same clinical spectrum (i.e. milder phenotypes), but also result in similar electrophysiological consequences (loss-of-function) opposing those of misTMD+Linker (severe phenotypes; predominantly gain-of-function). This new pathomechanistic model may ultimately help in predicting phenotype severity as well as eligibility for potential precision medicine approaches in GRIN2A-related disorders.
Acute flaccid myelitis is characterized by the combination of acute flaccid paralysis and a spinal cord lesion largely restricted to the gray matter on magnetic resonance imaging. The term acute ...flaccid myelitis was introduced in 2014 after the upsurge of pediatric cases in the USA with enterovirus D68 infection. Since then, an increasing number of cases have been reported worldwide. Whereas the terminology is new, the clinical syndrome has been recognized in the past in association with several other neurotropic viruses such as poliovirus.
Conclusion
: This review presents the current knowledge on acute flaccid myelitis with respect to the clinical presentation and its differential diagnosis with Guillain-Barré syndrome and acute transverse myelitis. We also discuss the association with enterovirus D68 and the presumed pathophysiological mechanism of this infection causing anterior horn cell damage. Sharing clinical knowledge and insights from basic research is needed to make progress in diagnosis, treatment, and prevention of this new polio-like disease.
What is Known:
•
Acute flaccid myelitis (AFM) is a polio-like condition characterized by rapid progressive asymmetric weakness, together with specific findings on MRI
• AFM has been related to different viral agents, but recent outbreaks are predominantly associated with enterovirus D68.
What is New:
•
Improving knowledge on AFM must increase early recognition and adequate diagnostic procedures by clinicians.
• The increasing incidence of AFM urges cooperation between pediatricians, neurologists, and microbiologists for the development of treatment and preventive options.
Background and purpose
Acute flaccid myelitis (AFM) and transverse myelitis (TM) are serious conditions that may be difficult to differentiate, especially at onset of disease. In this study, we ...compared clinical features of pediatric AFM and TM and evaluated current diagnostic criteria, aiming to improve early and accurate diagnosis.
Methods
Two cohorts of children with enterovirus D68‐associated AFM and clinically diagnosed TM were compared regarding presenting clinical features, additional investigations, and outcome. Current diagnostic criteria for AFM and TM were applied to evaluate their specificity.
Results
Children with AFM (n = 21) compared to those with TM (n = 36) were younger (median 3 vs. 10 years), more often had a prodromal illness (100% vs. 39%), predominant proximal weakness (69% vs. 17%), and hyporeflexia (100% vs. 44%), and less often had sensory deficits (0% vs. 81%), bowel and/or bladder dysfunction (12% vs. 69%), and hyperreflexia (0% vs. 44%). On magnetic resonance imaging, brainstem involvement was more common in AFM (74% vs. 21%), whereas supratentorial abnormalities were only seen in TM (0% vs. 40%). When omitting the criterion of a sensory level, 11 of 15 (73%) children with AFM fulfilled the diagnostic criteria for TM. Of children with TM, four of 33 (12%) fulfilled the diagnostic criteria for probable/definite AFM.
Conclusions
Although there is considerable overlap between AFM and TM in children, we found important early differentiating clinical and diagnostic features. Meeting diagnostic criteria for AFM in children with TM and vice versa underlines the importance of thorough clinical examination and early and accurate diagnostic studies.
BACKGROUND:Enterovirus-D68 (EV-D68) is a respiratory virus within the genus Enterovirus and the family of Picornaviridae. Genetically, it is closely related to rhinovirus that replicates in the ...respiratory tract and causes respiratory disease. Since 2014, EV-D68 has been associated with the neurologic syndrome of acute flaccid myelitis (AFM).
METHODS:In October 2016, questionnaires were sent out to a European network including 66 virologists and clinicians, to develop an inventory of EV-D68–associated AFM cases in Europe. Clinical and virologic information of case patients was requested. In addition, epidemiologic information on EV testing was collected for the period between March and October 2016.
RESULTS:Twenty-nine cases of EV-D68–associated AFM were identified, from 12 different European countries. Five originated from France, 5 from Scotland and 3 each from Sweden, Norway and Spain. Twenty-six were children (median age 3.8 years), 3 were adults. EV-D68 was detected in respiratory materials (n = 27), feces (n = 8) and/or cerebrospinal fluid (n = 2). Common clinical features were asymmetric flaccid limb weakness, cranial nerve deficits and bulbar symptoms. On magnetic resonance imaging, typical findings were hyperintensity of the central cord and/or brainstem; low motor amplitudes with normal conduction velocities were seen on electromyography. Full clinical recovery was rare (n = 3), and 2 patients died. The epidemiologic data from 16 European laboratories showed that of all EV-D68–positive samples, 99% was detected in a respiratory specimen.
CONCLUSIONS:For 2016, 29 EV-D68–related AFM cases were identified in mostly Western Europe. This is likely an underestimation, because case identification is dependent on awareness among clinicians, adequate viral diagnostics on respiratory samples and the capability of laboratories to type EVs.
•Sleep disturbances are more prevalent in people with epilepsy attending district hospitals than in controls without epilepsy.•Compared to controls PWE more often experience excessive daytime ...sleepiness with more pathological scores.•Sleep disturbance impacts on quality of life, especially in people with epilepsy.
Studies in adults with epilepsy, mainly in specialized epilepsy clinics, have shown that sleep disturbances were twice as prevalent in people with epilepsy as in healthy controls. Our aim was to determine the prevalence of sleep disturbances in people with epilepsy treated in district hospitals, as well as the impact of it on Quality of Life.
Adults with epilepsy, attending outpatient clinics in three district hospitals were invited to participate. Those who accepted (N = 122) provided their own controls matched for age and sex. Both groups completed four questionnaires (Groningen Sleep Quality Scale (GSQ), Medical Outcomes Study-Sleep scale (MOSS), Sleep Diagnosis List (SDL) and Epworth Sleepiness Scale) to measure their sleep over different periods and the 36-Item Short Form Health Survey (SF-36) to measure Quality of Life (QoL). The prevalence of sleep disturbances and scores on QoL were compared between both groups.
Sleep quality, measured by the SDL, was in the pathological range 50% more often in the epilepsy group than in controls. This was confirmed by the MOSSINDEX and GSQ. People with epilepsy experienced excessive daytime sleepiness more often than controls.
The lowest scores on nearly all domains of the SF-36 were seen in people with epilepsy and associated sleep disturbances.
We confirmed the higher prevalence of sleep disturbances in people with epilepsy compared to controls as previously reported from specialized settings. The (co-morbid) sleep disturbances result in lower QoL scores, in both people with epilepsy and in controls, but more in people with epilepsy.
Abstract Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder, associated with a variable clinical phenotype including café-au-lait spots, intertriginous freckling, Lisch nodules, ...neurofibromas, optic pathway gliomas and distinctive bony lesions. NF1 is caused by a mutation in the NF1 gene, which codes for neurofibromin, a large protein involved in the MAPK- and the mTOR-pathway through RAS-RAF signalling. NF1 is a known tumour predisposition syndrome, associated with different tumours of the nervous system including low grade gliomas (LGGs) in the paediatric population. The focus of this review is on grade I pilocytic astrocytomas (PAs), the most commonly observed histologic subtype of low grade gliomas in NF1. Clinically, these PAs have a better prognosis and show different localisation patterns than their sporadic counterparts, which are most commonly associated with a KIAA1549:BRAF fusion. In this review, possible mechanisms of tumourigenesis in LGGs with and without NF1 will be discussed, including the contribution of different signalling pathways and tumour microenvironment. Furthermore we will discuss how increased understanding of tumourigenesis may lead to new potential targets for treatment.
Aim Our aim was to compare the effect of prenatal endoscopic with postnatal myelomeningocele closure (fetally operated spina bifida aperta fSBA) versus neonatally operated spina bifida aperta nSBA) ...on segmental neurological leg condition.
Method Between 2003 and 2009, the fetal surgical team (Department of Obstetrics, University of Bonn, Germany) performed 19 fetal endoscopic procedures. Three procedures resulted in fetal death, three procedures were interrupted by iatrogenic hemorrhages and 13 procedures were successful. We matched each successfully treated fSBA infant with another nSBA infant of the same age and level of lesion, resulting in 13 matched pairs (mean age 14mo; SD 16mo; f/m=1.6; female‐16, male‐10). Matched fSBA and nSBA pairs were compared in terms of segmental neurological function and leg muscle ultrasound density (MUD). We also determined intraindividual difference in MUD (dMUD) between myotomes caudal and cranial to the myelomeningocele (reflecting neuromuscular damage by the myelomeningocele) and compared dMUD between fSBA and nSBA infants. Finally, we correlated dMUD with segmental neurological function.
Results We found that, on average, the fSBA group were born at a lower gestational age than the nSBA group (median 32wks range 25–34wks vs 39wks 34–41wks; p=0.001) and experienced more complications (chorioamnionitis, premature rupture of the amniotic membranes, oligohydramnios, and infant respiratory distress syndrome necessitating intermittent positive‐pressure ventilation). Neurological function was better preserved after fSBA than after nSBA (median motor and sensory gain of two segments; better preserved knee‐jerk p=0.006 and anal p=0.032 reflexes). The dMUD was smaller in fSBA than in nSBA infants (mean difference 24, 95% confidence interval CI 15–33; p<0.05), which was associated with better preserved segmental muscle function.
Interpretation Fetal endoscopic surgery is associated with spinal segmental neuroprotection, but it results in more complications. Before considering clinical implementation of fetal endoscopic myelomeningocele closure as standard care, the frequency of complications should be appropriately reduced and results assessed in larger groups over a longer period of time.
•Since 2012, new AEDs are most often prescribed in children.•Levetiracetam has replaced valproic acid in children as the most often initiated AED.•Personal preferences of specialists are important in ...prescribing AEDs in children.
In the last two decades several new antiepileptic drugs (AEDs) have become available. The aim of our study was to analyse whether and how AED prescribing patterns in Dutch children have changed during the last decade and whether these changes were supported by guidelines and results from recently available trials.
From a large community pharmacy-dispensing database in the Netherlands, we identified children aged 0–19 years who received at least one prescription for an AED between 2006 and 2014. Children who also received prescriptions for migraine or psychiatric disorders were excluded. We calculated year-prevalences and -incidences of AED use with emphasis on old versus new AEDs, and individual AEDs. We evaluated these results, including the course of AED prescribing.
During the study period, the prescribing prevalence of old AEDs decreased from 1.61 per 1000 (95% C.I. 1.40–1.82) to 1.39 per 1000 (95% C.I. 1.18–1.60); for new AEDs it increased from 0.58 per 1000 (95% C.I. 0.45–0.71) to 1.35 per 1000 (95% C.I. 1.14–1.56). Valproic acid was the most frequently initiated AED in 2006. From 2010, prescribing of old and new AEDs became equal with levetiracetam as the most often initiated AED since 2012. This drug was recommended for all seizure types in the 2013 Dutch national epilepsy guideline. Only 5.5% of the children used AED combination therapy. Of those on monotherapy, 85.7% remained on the first prescribed AED.
In the last 10 years, prescribing of new AEDs increased at the expense of old AEDs. Levetiracetam has replaced valproic acid as the most frequently prescribed first line antiepileptic drug in children since 2012, which is in line with national guidelines.
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