Clinical description, molecular delineation and genotype-phenotype correlation in 340 patients with KBG syndrome: addition of 67 new patients.

BACKGROUND: KBG syndrome is a highly variable neurodevelopmental disorder and clinical diagnostic criteria have changed as new patients have been reported. Both loss-of-function sequence variants and large deletions (copy number variations, CNVs) involving ANKRD11 cause KBG syndrome, but no genotype-phenotype correlation has been reported. METHODS: 67 patients with KBG syndrome were assessed using a custom phenotypical questionnaire. Manifestations present in >50% of the patients and a 'phenotypical score' were used to perform a genotype-phenotype correlation in 340 patients from our cohort and the literature. RESULTS: Neurodevelopmental delay, macrodontia, triangular face, characteristic ears, nose and eyebrows were the most prevalentf (eatures. 82.8% of the patients had at least one of seven main comorbidities: hearing loss and/or otitis media, visual problems, cryptorchidism, cardiopathy, feeding difficulties and/or seizures. Associations found included a higher phenotypical score in patients with sequence variants compared with CNVs and a higher frequency of triangular face (71.1% vs 42.5% in CNVs). Short stature was more frequent in patients with exon 9 variants (62.5% inside vs 27.8% outside exon 9), and the prevalence of intellectual disability/attention deficit hyperactivity disorder/autism spectrum disorder was lower in patients with the c.1903_1907del variant (70.4% vs 89.4% other variants). Presence of macrodontia and comorbidities were associated with larger deletion sizes and hand anomalies with smaller deletions. CONCLUSION: We present a detailed phenotypical description of KBG syndrome in the largest series reported to date of 67 patients, provide evidence of a genotype-phenotype correlation between some KBG features and specific ANKRD11 variants in 340 patients, and propose updated clinical diagnostic criteria based on our findings.

Sleep Problems, Circadian Rhythms, and Their Relation to Behavioral Difficulties in Children and Adolescents with Autism Spectrum Disorder.

This was an exploratory cross-sectional study comparing 45 children with ASD to 24 typically developing drug-naïve controls, group-matched on age, sex, and body mass index. Objective data was obtained using the following: an ambulatory circadian monitoring device; saliva samples to determine dim light melatonin onset (DLMO): and three parent-completed measures: the Child Behavior Checklist (CBCL); the Repetitive Behavior Scale-Revised (RBS-R); and the General Health Questionnaire (GHQ28). The CBCL and RBS-R scales showed the highest scores amongst poor sleepers with ASD. Sleep fragmentation was associated with somatic complaints and self-injury, leading to a higher impact on family life. Sleep onset difficulties were associated with withdrawal, anxiety, and depression. Those with phase advanced DLMO had lower scores for "somatic complaints"; "anxious/depressed" state; and "social problems", suggesting that this phenomenon has a protective role.

Melatonin Rhythm and Its Relation to Sleep and Circadian Parameters in Children and Adolescents With Autism Spectrum Disorder.

Introduction: Sleep problems are prevalent among individuals with autism spectrum disorder (ASD), and a role has been attributed to melatonin in this multifactorial comorbidity. Methods: A cross-sectional study was conducted on 41 autistic children and adolescents (9.9 ± 3.02) and 24 children and adolescents with a normal intellectual function (8.42 ± 2.43) were used as controls. Subjects were matched for sex, body mass index, and pubertal stage, and all were drug-naive. Circadian and sleep parameters were studied using an ambulatory circadian monitoring (ACM) device, and saliva samples were collected around the onset of sleep to determine dim light melatonin onset (DLMO). Results: Prepubertal individuals with ASD presented later DLMO and an earlier decline in melatonin during adolescence. A relationship was found between melatonin and both sleep and circadian parameters. Participants and controls with later DLMOs were more likely to have delayed sleep onset times. In the ASD group, subjects with the later daytime midpoint of temperature had a later DLMO. Later melatonin peak time and DLMO time were related to lower general motor activity and lower stability of its rhythms. Conclusion: The melatonin secretion pattern was different in individuals with ASD, and it showed a relationship with sleep and circadian parameters. Alterations in DLMO have not been previously reported in ASD with the exception of more variable DLMO timing; however, high variability in the study design and sample characteristics prevents direct comparison. The ACM device enabled the measurement of circadian rhythm, a scarcely described parameter in autistic children. When studied in combination with other measures such as melatonin, ACM can offer further knowledge on sleep problems in ASD.

Attention Deficit Hyperactivity and Autism Spectrum Disorders as the Core Symptoms of AUTS2 Syndrome: Description of Five New Patients and Update of the Frequency of Manifestations and Genotype-Phenotype Correlation.

Haploinsufficiency of AUTS2 has been associated with a syndromic form of neurodevelopmental delay characterized by intellectual disability, autistic features, and microcephaly, also known as AUTS2 syndrome. While the phenotype associated with large deletions and duplications of AUTS2 is well established, clinical features of patients harboring AUTS2 sequence variants have not been extensively described. In this study, we describe the phenotype of five new patients with AUTS2 pathogenic variants, three of them harboring loss-of-function sequence variants. The phenotype of the patients was characterized by attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) or autistic features and mild global developmental delay (GDD) or intellectual disability (ID), all in 4/5 patients (80%), a frequency higher than previously reported for ADHD and autistic features. Microcephaly and short stature were found in 60% of the patients; and feeding difficulties, generalized hypotonia, and ptosis, were each found in 40%. We also provide the aggregated frequency of the 32 items included in the AUTS2 syndrome severity score (ASSS) in patients currently reported in the literature. The main characteristics of the syndrome are GDD/ID in 98% of patients, microcephaly in 65%, feeding difficulties in 62%, ADHD or hyperactivity in 54%, and autistic traits in 52%. Finally, using the location of 31 variants from the literature together with variants from the five patients, we found significantly higher ASSS values in patients with pathogenic variants affecting the 3' end of the gene, confirming the genotype-phenotype correlation initially described.

Glut1 deficiency is a rare but treatable cause of childhood absence epilepsy with atypical features.

Glucose transporter type 1 deficiency syndrome (GLUT1-DS) is a rare genetic disorder caused by pathogenic variants in SLC2A1, resulting in impaired glucose uptake through the blood-brain barrier. Our objective is to analyze the frequency of GLUT1-DS in patients with absences with atypical features. Sequencing analysis and detection of copy number variation of the SLC2A1 gene was carried out in patients with atypical absences including: early-onset absence, intellectual disability, additional seizure types, refractory epilepsy, associated movement disorders, as well as those who have first-degree relatives with absence epilepsy or atypical EEG ictal discharges. Of the 43 patients analyzed, pathogenic variations were found in 2 (4.6%). Six atypical characteristics were found in these 2 patients. The greater the number of atypical characteristics presenting in patients with absence seizures, the more likely they have a SLC2A1 mutation. Although GLUT1-DS is an infrequent cause of absence epilepsy, recognizing this disorder is important, since initiation of a ketogenic diet can reduce the frequency of seizures, the severity of the movement disorder, and also improve the quality of life of the patients and their families.

[Do children with attention deficit and hyperactivity disorder (ADHD) have a diferent gait pattern? Relationship between idiopathic toe-walking and ADHD]. / ¿Caminan de manera diferente los niños con trastorno por déficit de atención hiperactividad (TDAH)? Relación entre marcha de puntillas idiopática y TDAH.

INTRODUCTION: Idiopathic toe-walking (ITW) is described as a gait pattern with no contact between the heels and the ground in children older than 3years. The diagnosis is clinical, making it necessary to rule out other neurological and orthopaedic conditions. A relationship between ITW and vestibular dysfunction and/or proprioceptive sensibility has been proposed. Children with neurodevelopmental disorders (autism, language and cognitive disorders) often have ITW. OBJECTIVES: To determine the frequency of ITW in children with attention deficit disorder and hyperactivity (ADHD). PATIENTS AND METHOD: A study was conducted on children diagnosed with ADHD, with normal neurological examination, with no alterations in MRI scan, cognitive disorder or autism. A complete clinical anamnesis was performed and Achilles shortening was measured with a goniometer. RESULTS: The study included 312 children with a mean age of 11 years (73.7% boys). The ADHD combined subtype was the most frequent (53.8%), followed by the inattentive (44.9%), and hyperactive (1.3%). ITW was observed in 20.8% of patients, particularly in the combined subtype (P=.054). Only 32 of them (49.2%) had Achilles shortening. ITW was associated with sociability disorders (P=.01), absence of pain in legs (P=.022), and family history of ITW (P=.004). Only 11% had previously visited a doctor for this reason. CONCLUSIONS: As in other neurodevelopmental disorders, children with ADHD have frequently more ITW and Achilles shortening than controls, especially if they presented with a social communication disorder or a family history of ITW. An early diagnosis is essential to establish effective treatments.

Molecular diagnosis of patients with epilepsy and developmental delay using a customized panel of epilepsy genes.

Pediatric epilepsies are a group of disorders with a broad phenotypic spectrum that are associated with great genetic heterogeneity, thus making sequential single-gene testing an impractical basis for diagnostic strategy. The advent of next-generation sequencing has increased the success rate of epilepsy diagnosis, and targeted resequencing using genetic panels is the a most cost-effective choice. We report the results found in a group of 87 patients with epilepsy and developmental delay using targeted next generation sequencing (custom-designed Haloplex panel). Using this gene panel, we were able to identify disease-causing variants in 17 out of 87 (19.5%) analyzed patients, all found in known epilepsy-associated genes (KCNQ2, CDKL5, STXBP1, SCN1A, PCDH19, POLG, SLC2A1, ARX, ALG13, CHD2, SYNGAP1, and GRIN1). Twelve of 18 variants arose de novo and 6 were novel. The highest yield was found in patients with onset in the first years of life, especially in patients classified as having early-onset epileptic encephalopathy. Knowledge of the underlying genetic cause provides essential information on prognosis and could be used to avoid unnecessary studies, which may result in a greater diagnostic cost-effectiveness.

[The importance of sleep problems in children with headache and other neurodevelopmental disorders in neuropaediatric services]. / Importancia de los problemas de sueño en los niños con cefalea y otros trastornos del neurodesarrollo en las consultas de neuropediatria.

INTRODUCTION: Sleep disorders are common in children with neurological disorders. The aim of this study is to know the opinion of neuropediatricians and the prevalence of these disturbances in Spain. PATIENTS AND METHODS: Multicenter cross-sectional study (12 Spanish hospitals, 15 researchers). BEARS survey was collected in three groups: A (2-5 years), (6-12 years), and C (> 12 years). The opinion of neuropediatricians was also collected. RESULTS: 939 questionnaires were filled. The main results in groups B and C were ADHD (32.4% and 30.1% respectively) and headache (25.1% and 27.6% respectively), whereas in group A neurodevelopmental disorders (32.4%) and epilepsy (21.4%) were the main diagnoses. Disturbances in at least one area of sleep were found in 92% of children in group A (n = 209, mean 3 years), 64.2% in group B (n = 534, mean 9.4 years) and 58.2% in group C (n = 196, mean 13.7 years). Sixty-one surveys were answered by neuropediatricians (16.75% of the total sent), estimating that less than a quarter of the patients (24.5%) suffered. Even, up to 23% of doctors claimed that the prevalence of sleep disorders was < 10%. CONCLUSIONS: 58-92% of parents-patients under follow up at a neuropediatrician office in Spain have some degree of disturbed sleep. Although most neurologists emphasize the importance of an early diagnosis and treatment of sleep disorders in children with neurological disorders, its frequency is often underestimated (risk of underdiagnosis).

TITLE: Importancia de los problemas de sueño en los niños con cefalea y otros trastornos del neurodesarrollo en las consultas de neuropediatria.Introduccion. Los trastornos de sueño son frecuentes en niños con trastornos neurologicos. El objetivo del estudio es conocer la opinion de los neuropediatras y su prevalencia real en España. Pacientes y metodos. Estudio transversal multicentrico (12 hospitales españoles, 15 investigadores). Se administro la encuesta Bedtime, Excesive Daytime Sleepiness, Awakenings, Regularity, Sleep-Disordered Breathing (BEARS) y se definieron tres grupos: A (2-5 años), B (6-12 años) y C (> 12 años). Asimismo, se recogio la opinion de neuropediatras de la Sociedad Española de Neuropediatria mediante una encuesta anonima. Resultados. Se recogieron 939 encuestas. Los principales motivos de consulta en los grupos B y C fueron trastorno por deficit de atencion/hiperactividad (32,4% y 30,1%, respectivamente) y cefalea (25,1% y 27,6%, respectivamente), y en el grupo A, los trastornos del neurodesarrollo (32,4%) y la epilepsia (21,4%). Al menos un area del sueño alterada se encontro en el 92,9% de niños del grupo A (n = 209; media: 3 años), en el 64,2% del grupo B (n = 534; media: 9,4 años) y en el 58,2% del grupo C (n = 196; media: 13,7 años). Se recibieron 61 encuestas respondidas por los neuropediatras (16,75% de las enviadas), quienes estimaban que los trastornos del sueño afectaban a menos de una cuarta parte de sus pacientes (24,5%), y hasta un 23% afirmo que la prevalencia era inferior al 10%. Conclusion. El 58-92% de los padres-pacientes que acuden a consultas de neuropediatria refiere tener algun aspecto del sueño alterado. Aunque la mayoria de los neuropediatras subraya la importancia de un diagnostico y tratamiento de los trastornos de sueño de los niños con trastornos neurologicos, se suele infraestimar su frecuencia e importancia.