The Two Faces of Pediatric SCA2.

Introduction: Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurological disease usually described in adults. Expanded CAG repeats in the ATXN2 gene can lead to pediatric onset. This study aims to describe the natural history of SCA2 in children.

Triheptanoin Did Not Show Benefit versus Placebo for the Treatment of Paroxysmal Movement Disorders in Glut1 Deficiency Syndrome: Results of a Randomized Phase 3 Study.

Background: Paroxysmal movement disorders are common in Glut1 deficiency syndrome (Glut1DS). Not all patients respond to or tolerate ketogenic diets.

Objectives: The objective was to evaluate the effectiveness and safety of triheptanoin in reducing the frequency of disabling movement disorders in patients with Glut1DS not receiving a ketogenic diet.

Non-Motor Symptoms and Quality of Life in Patients with PRRT2-Related Paroxysmal Kinesigenic Dyskinesia.

Background: Monoallelic pathogenic variants of often result in paroxysmal kinesigenic dyskinesia (PKD). Little is known about health-related quality of life (HrQoL), non-motor manifestations, self-esteem, and stigma in patients with PKD.

Objectives: We investigated non-motor symptoms and how they related to HrQoL in a genetically homogeneous group of -PKD patients.

Intraputaminal Gene Delivery in Two Patients with Aromatic L-Amino Acid Decarboxylase Deficiency.

Background: Aromatic l-amino acid decarboxylase deficiency (AADCD) is a rare, early-onset, dyskinetic encephalopathy mostly reflecting a defective synthesis of brain dopamine and serotonin. Intracerebral gene delivery (GD) provided a significant improvement among AADCD patients (mean age, ≤6 years).

Objective: We describe the clinical, biological, and imaging evolution of two AADCD patients ages >10 years after GD.

Prospective Multicenter Validation of a Simple Blood Test for the Diagnosis of Glut1 Deficiency Syndrome.

Background And Objective: GLUT1 deficiency syndrome (Glut1DS) is a treatable neurometabolic disease that causes a wide range of neurologic symptoms in children and adults. However, its diagnosis relies on an invasive test, that is, a lumbar puncture (LP) to measure glycorrhachia, and sometimes complex molecular analyses of the gene. This procedure limits the number of patients able to receive the standard of care.

Developmental coordination disorder subtypes in children: An unsupervised clustering.

Aim: To identify subtypes of developmental coordination disorder (DCD) in children.

Method: Children with DCD diagnosed through comprehensive evaluation at Robert-Debré Children's University Hospital (Paris, France) were consecutively enrolled from February 2017 to March 2020. We performed an unsupervised hierarchical clustering based on principal component analysis using a large set of variables encompassing cognitive, motor, and visuospatial scores (Wechsler Intelligence Scale for Children, Fifth Edition; Developmental Neuropsychological Assessment, Second Edition; Movement Assessment Battery for Children, Second Edition).

A recurrent de novo splice site variant involving DNM1 exon 10a causes developmental and epileptic encephalopathy through a dominant-negative mechanism.

Heterozygous pathogenic variants in DNM1 cause developmental and epileptic encephalopathy (DEE) as a result of a dominant-negative mechanism impeding vesicular fission. Thus far, pathogenic variants in DNM1 have been studied with a canonical transcript that includes the alternatively spliced exon 10b. However, after performing RNA sequencing in 39 pediatric brain samples, we find the primary transcript expressed in the brain includes the downstream exon 10a instead.

GM3 synthase deficiency in non-Amish patients.

Purpose: Biallelic loss-of-function variants in ST3GAL5 cause GM3 synthase deficiency (GM3SD) responsible for Amish infantile epilepsy syndrome. All Amish patients carry the homozygous p.(Arg288Ter) variant arising from a founder effect.

Opsoclonus-myoclonus in Aicardi-Goutières syndrome.

Aicardi-Goutières syndrome (AGS) is a rare genetic neuroinflammatory disorder caused by abnormal upregulation of type 1 interferon signalling. Opsoclonus-myoclonus syndrome is a rare autoimmune phenotype demonstrating a disturbance in the humoral immune response mostly seen in the context of paraneoplastic or postinfectious states, although its pathophysiology is incompletely understood. We report the first three children described with AGS demonstrating transient opsoclonus and myoclonus after irritability and/or developmental regression, suggesting a pathological association.

[Movement disorders in children].

Movement disorders in children. The phenomenological spectrum of pediatric movement disorders is wide and correspond to a large variety of causes. It comprises fixed transient, and progressive disorders.

Early-onset nucleotide excision repair disorders with neurological impairment: Clues for early diagnosis and prognostic counseling.

Nucleotide excision repair associated diseases comprise overlapping phenotypes and a wide range of outcomes. The early stages still remain under-investigated and underdiagnosed, even although an early recognition of the first symptoms is of utmost importance for appropriate care and genetic counseling. We systematically collected clinical and molecular data from the literature and from newly diagnosed NER patients with neurological impairment, presenting clinical symptoms before the age of 12 months, including foetal cases.

Usefulness of diagnostic tools in a GLUT1 deficiency syndrome patient with 2 inherited mutations.

Unlabelled: In some patients with GLUT1 deficiency syndrome (GLUT1-DS), the diagnosis can be difficult to reach. We report a child with 2 inherited mutations suggesting an autosomal recessive transmission of SLC2A1 mutations.

Methods: The child and her parents were explored with erythrocyte 3-O-methyl-d-Glucose uptake, glucose uptake in oocytes expressing GLUT1 with the gene mutations and measure of the expression of GLUT1 at the surface of the circulating red blood cells by flow cytometry (METAglut1™ test).

Spinal muscular atrophy with respiratory distress type 1: A multicenter retrospective study.

Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disorder characterized by progressive motor and respiratory decline during the first year of life. Early and late-onset cases have recently been reported, although not meeting the established diagnostic criteria, these cases have been genotyped. We thus conducted a national multicenter observational retrospective study to determine the prognosis of children with SMARD1 according to their phenotype.

A simple blood test expedites the diagnosis of glucose transporter type 1 deficiency syndrome.

Glucose transporter type 1 (GLUT1) deficiency syndrome (GLUT1-DS) leads to a wide range of neurological symptoms. Ketogenic diets are very efficient to control epilepsy and movement disorders. We tested a novel simple and rapid blood test in 30 patients with GLUT1-DS with predominant movement disorders, 18 patients with movement disorders attributed to other genetic defects, and 346 healthy controls.

Use of modified Atkins diet in glucose transporter type 1 deficiency syndrome.

Aim: Glucose transporter type 1 deficiency syndrome (GLUT1-DS) results from impaired glucose transport into the brain, and is treated with a ketogenic diet. A few reports have suggested effectiveness of treatment using the modified Atkins diet (MAD). We aimed to assess the efficacy of MAD as a treatment for GLUT1-DS.