Phenotypic Spectrum of STXBP1 Gene Mutations in an Emirati Case Series.

Genetic mutations are increasingly recognized as etiologic factors for epilepsy and neurodevelopmental disorders. Loss of function mutations in STXBP1, one of such genes, has, in recent years, been demonstrated to cause a broad spectrum of epilepsy syndromes and chronic neurodisabilities. Syntaxin-binding protein 1 (STXBP1) is a well-recognized membrane trafficking protein responsible for synaptic transmission and is expressed ubiquitously across the brain. Our case series presents the neurodevelopmental phenotype of children with STXBP1 mutations and is the first to be reported in an Emirati patient cohort. We gathered data on five children with genetically confirmed STXBP1 mutations, each displaying varying symptomatology, EEG features, response to antiepileptic medications, and eventual disease progression. This report reveals that a majority of STXBP1 mutations were de-novo in origin; heterozygous; pathogenic to likely pathogenic variants; clinical disease onset was predominantly during infancy in the form of developmental delays with or without seizures; most of the children had co-existing ADHD or autism spectrum disorders; typical seizure semiology at onset was in the form of infantile spasms, progressing to a melange of mixed seizure types; seizure control on antiepileptic drug therapy was variable, with all cases requiring more than two medications; global developmental delay was noted in all studied children; and MRI brain findings were unremarkable in all cases. This case series demonstrates a degree of uniformity of STXBP1 mutation disease phenotypes with international literature and provides a unique insight into the genetic profile of affected children within the Emirati population.

Heterozygous gain of function variants in a critical region of RNF13 cause congenital microcephaly, epileptic encephalopathy, blindness, and failure to thrive.

Missense variants in the RNF13 gene have been previously known to cause congenital microcephaly, epileptic encephalopathy, blindness, and failure to thrive through a gain-of-function disease mechanism. Here, we identify a nonsense variant, expected to result in protein truncation, in a similarly affected patient. We show that this nonsense variant, residing in the terminal exon, is likely to escape nonsense-mediated decay while removing a critical region for protein function, thus resulting in a gain-of-function effect. We review the literature and disease databases and identify several other affected individuals with overlapping phenotypes carrying distinct truncating variants in the terminal exon upstream of the putative critical region. Furthermore, we analyze truncating variants from the general population, namely, the Genome Aggregation Database (gnomAD), and provide additional evidence supporting our hypothesis, and ruling out haploinsufficiency as an alternative disease mechanism. In summary, our case report, literature review, and analysis of disease and population databases strongly support the hypothesis that heterozygous gain-of-function variants in a critical region of RNF13 cause congenital microcephaly, epileptic encephalopathy, blindness, and failure to thrive.

Current management of Duchenne muscular dystrophy in the Middle East: expert report.

Aim: Duchenne muscular dystrophy (DMD) is a severe and rare X-linked neuromuscular childhood disorder that results in functional decline, loss of ambulation and early death due to cardiac or respiratory failure. The objective of this paper is to address different aspects of the current management of DMD in the Middle East, north Africa (MENA) region, and to gather experts' recommendations on how to optimally diagnose and treat patients suffering from this disease. Methods: A group of experts (neuromuscular medicine, neuropediatricians and geneticists) convened to discuss the diagnosis and management of DMD in the MENA region. A list of practical statements was prepared by the chair of the meeting to guide the discussions around critical aspects relating to the current and future management of DMD. Results & conclusion: Ideally, DMD management should be a multidisciplinary approach. Nevertheless, few tertiary care hospitals in the region are currently able to provide the full spectrum of medical expertise and services needed by DMD patients. Clinical practice in the region remains heterogeneous. Specific guidelines for diagnosis and treatment are needed in the MENA region to improve outcomes. Disease awareness among the general public and the medical community is lacking. Now that mutation-specific therapies are being developed and more widely studied, general education programs regarding early signs and symptoms, a standardized referral and diagnosis pathway, patient registries and support groups will significantly improve the management of the disease.

Successful treatment of two paediatric cases of anti-NMDA receptor encephalitis with cyclophosphamide: the need for early aggressive immunotherapy in tumour negative paediatric patients.

We describe the clinical course and treatment of three unrelated female patients ranging in age from 27 months to 14 years with anti-NMDA receptor encephalitis. The third case is reported as an addendum to the paper. None of the cases were paraneoplastic. All received initial immunotherapy consisting of steroids and IVIg, and two of them received 3 and 8 plasma exchanges respectively, without consistent or sustained clinical improvement. All three girls were then treated with monthly cycles of Cyclophosphamide. All had resolution of their movement disorder and a dramatic and sustained clinical improvement of their other symptoms in the domains of cognition, language and behaviour. The clinical improvement began after the first cycle in two and the second cycle in the third and continued with the subsequent cycles. None developed side-effects of treatment. In light of the recent review of the condition and our own clinical experience in the paediatric age group, we propose that second line immunotherapy should be considered early after failure of first line immunotherapy.

Parental and physician beliefs regarding the provision and content of written sudden unexpected death in epilepsy (SUDEP) information.

PURPOSE: The 2007 UK National Institute for Health and Clinical Excellence (NICE) guidelines for epilepsy recommend disclosing the risk of sudden unexpected death in epilepsy (SUDEP) to patients. This recommendation is not undertaken routinely, and considerable variation in individual physician practice exists. Literature indicates wariness of causing distress and anxiety, particularly to children/young people and their families through disclosing a nonpreventable risk. There has been no systematic pediatric study examining parent/guardian information needs and beliefs for risk of SUDEP and its impact on seizure management. It is important to first address these concerns before routinely imparting SUDEP information to parents following NICE recommendations. METHODS: Two questionnaire surveys: a questionnaire examining the provision by pediatric neurologists of SUDEP information, and questionnaires examining parental beliefs and implications at two time points regarding SUDEP information provided in a leaflet. Participants were included in the study if their child had an established diagnosis of epilepsy. Factors for exclusion were single unprovoked seizure, absence seizures, patients in remission, and active discontinuation of treatment. RESULTS: The majority (74%) of pediatric neurologists provided SUDEP information only to a select group of children with epilepsy and were uncertain about the effect such information would have upon the parent and child. Conversely, 91% of parents expected the pediatric neurologist to provide SUDEP risk information. The provision of this information did not have a significant immediate and longer-term negative impact. DISCUSSION: The majority of parents wanted to know about SUDEP and its associated risks. Whenever possible, SUDEP information should be given by the physician accompanied by an information leaflet.