De novo loss-of-function KCNMA1 variants are associated with a new multiple malformation syndrome and a broad spectrum of developmental and neurological phenotypes.

KCNMA1 encodes the large-conductance Ca2+- and voltage-activated K+ (BK) potassium channel α-subunit, and pathogenic gain-of-function variants in this gene have been associated with a dominant form of generalized epilepsy and paroxysmal dyskinesia. Here, we genetically and functionally characterize eight novel loss-of-function (LoF) variants of KCNMA1. Genome or exome sequencing and the participation in the international Matchmaker Exchange effort allowed for the identification of novel KCNMA1 variants. Patch clamping was used to assess functionality of mutant BK channels. The KCNMA1 variants p.(Ser351Tyr), p.(Gly356Arg), p.(Gly375Arg), p.(Asn449fs) and p.(Ile663Val) abolished the BK current, whereas p.(Cys413Tyr) and p.(Pro805Leu) reduced the BK current amplitude and shifted the activation curves toward positive potentials. The p.(Asp984Asn) variant reduced the current amplitude without affecting kinetics. A phenotypic analysis of the patients carrying the recurrent p.(Gly375Arg) de novo missense LoF variant revealed a novel syndromic neurodevelopmental disorder associated with severe developmental delay, visceral and cardiac malformations, connective tissue presentations with arterial involvement, bone dysplasia and characteristic dysmorphic features. Patients with other LoF variants presented with neurological and developmental symptoms including developmental delay, intellectual disability, ataxia, axial hypotonia, cerebral atrophy and speech delay/apraxia/dysarthria. Therefore, LoF KCNMA1 variants are associated with a new syndrome characterized by a broad spectrum of neurological phenotypes and developmental disorders. LoF variants of KCNMA1 cause a new syndrome distinctly different from gain-of-function variants in the same gene.

Cannabidiol improves frequency and severity of seizures and reduces adverse events in an open-label add-on prospective study.

The objective of this study was to characterize the changes in adverse events, seizure severity, and frequency in response to a pharmaceutical formulation of highly purified cannabidiol (CBD; Epidiolex®) in a large, prospective, single-center, open-label study. We initiated CBD in 72 children and 60 adults with treatment-resistant epilepsy (TRE) at 5 mg/kg/day and titrated it up to a maximum dosage of 50 mg/kg/day. At each visit, we monitored treatment adverse events with the adverse events profile (AEP), seizure severity using the Chalfont Seizure Severity Scale (CSSS), and seizure frequency (SF) using seizure calendars. We analyzed data for the enrollment and visits at 12, 24, and 48 weeks. We recorded AEP, CSSS, and SF at each follow-up visit for the weeks preceding the visit (seizures were averaged over 2-week periods). Of the 139 study participants in this ongoing study, at the time of analysis, 132 had 12-week, 88 had 24-week, and 61 had 48-week data. Study retention was 77% at one year. There were no significant differences between participants who contributed all 4 data points and those who contributed 2 or 3 data points in baseline demographic and AEP/SF/CSSS measures. For all participants, AEP decreased between CBD initiation and the 12-week visit (40.8 vs. 33.2; p < 0.0001) with stable AEP scores thereafter (all p ≥ 0.14). Chalfont Seizure Severity Scale scores were 80.7 at baseline, decreasing to 39.2 at 12 weeks (p < 0.0001) and stable CSSS thereafter (all p ≥ 0.19). Bi-weekly SF decreased from a mean of 144.4 at entry to 52.2 at 12 weeks (p = 0.01) and remained stable thereafter (all p ≥ 0.65). Analyses of the pediatric and adult subgroups revealed similar patterns. Most patients were treated with dosages of CBD between 20 and 30 mg/kg/day. For the first time, this prospective, open-label safety study of CBD in TRE provides evidence for significant improvements in AEP, CSSS, and SF at 12 weeks that are sustained over the 48-week duration of treatment.

UBQLN2 mutation causing heterogeneous X-linked dominant neurodegeneration.

We report a 5-generation family with phenotypically diverse neurodegenerative disease including relentlessly progressive choreoathetoid movements, dysarthria, dysphagia, spastic paralysis, and behavioral dementia in descendants of a 67-year-old woman with amyotrophic lateral sclerosis. Disease onset varied with gender, occurring in male children and adult women. Exome sequence analyses revealed a novel mutation (c.1490C>T, p.P497L) in the ubiquilin-2 gene (UBQLN2) with X-linked inheritance in all studied affected individuals. As ubiquilin-2-positive inclusions were identified in brain, we suggest that mutant peptide predisposes to protein misfolding and accumulation. Our findings expand the spectrum of neurodegenerative phenotypes caused by UBQLN2 mutations.

Content Validation of the Movement Disorder-Childhood Rating Scale (MD-CRS) for Dyskinetic Cerebral Palsy.

BACKGROUND: Dyskinetic cerebral palsy (DCP), a lifelong neurological disorder beginning in early childhood, manifests with hyperkinetic movements and dystonia. The Movement Disorder-Childhood Rating Scale (MD-CRS) is a clinician-reported outcome measure assessing the intensity of movement disorders and their effect on daily life in pediatric patients. Content validity of clinical outcome assessments is key to accurately capturing patient perspective. Evidence demonstrating content validity of the MD-CRS in patients with DCP is needed. This study captures input from patients with DCP and their caregivers regarding the content validity of the MD-CRS. METHODS: This qualitative, noninterventional, cross-sectional study included interviews with children/adolescents (aged six to 18 years) with DCP and caregivers of children with DCP. Participants were asked to describe body regions and daily functions affected by DCP. Caregivers also reviewed MD-CRS Part I to evaluate the relevance of the items and corresponding response options. Descriptions of DCP were coded and mapped to MD-CRS items and response options. Caregiver feedback on MD-CRS Part I was analyzed using inductive content analysis. RESULTS: Eight patients and 12 caregivers were interviewed. Participants confirmed that the body regions and activities listed in the MD-CRS were affected by DCP and that involuntary movements interfered with all motor, oral/verbal, self-care, and video protocol activities. Caregivers endorsed the response options for 12 of 15 items in MD-CRS Part I and suggested clarifications for others. CONCLUSIONS: Participants confirmed that affected body regions and activities listed in the MD-CRS were relevant to their experience with DCP, demonstrating the content validity of this tool in children/adolescents with DCP.

Females experience a more severe disease course in Batten disease.

Juvenile neuronal ceroid lipofuscinosis (JNCL; CLN3 disease; Batten disease) is an autosomal recessive neurodegenerative disease of childhood. Symptoms typically present at school age with vision loss followed by progressive cognitive decline, motor dysfunction, seizures, and behavior problems. Studies on sex differences in JNCL have yielded mixed results, but parent anecdotes suggest that females experience a more precipitous disease course. Therefore, we sought to determine if sex-based differences exist in JNCL. We used data from the Unified Batten Disease Rating Scale (UBDRS), the Batten Disease Support and Research Association (BDSRA) database, and the PedsQL quality of life (QoL) survey to evaluate sex-based differences in functional independence and time from symptom onset to death. On average, females had JNCL symptom onset one year later and death one year earlier than did males. Despite a later age at onset, females had lower functional capability, earlier loss of independent function, and lower physical QoL. Future research in sex differences in JNCL may help to further understand the biological mechanisms underpinning the disease course and may point to targeted therapies.

Spinal Cord Diffuse Midline Glioma in a 4-Year-Old Boy.

OBJECTIVE: We report a child presenting with spinal myelopathy secondary to H3K27M mutant diffuse midline glioma. CASE REPORT: A 4-year-old boy presented with a 3-week history of progressive gait difficulty. Examination revealed bilateral hand and lower extremity weakness, left leg hypertonia with ankle clonus, and a right hemisensory deficit. Magnetic resonance imaging of neuroaxis showed cervical and thoracic spinal cord with expansion and irregular areas of enhancement. Serum and cerebrospinal fluid studies were unremarkable for infectious, autoimmune, inflammatory, and neoplastic causes but showed mild cerebrospinal fluid pleocytosis, hypoglycorrhachia, and high protein level. A thoracic cord biopsy revealed a diffuse midline glioma (World Health Organization grade IV). Consequently, the tumor involved intracranial structures and patient died within 4 months after diagnosis. CONCLUSION: High-grade spinal cord gliomas are very rare but should be considered in the differential diagnosis of pediatric myelopathy. Tissue biopsy is recommended in indeterminate cases to facilitate diagnosis and to guide management.

A pilot assessment of parental practices and attitudes regarding risk disclosure and clinical research involving children in Huntington disease families.

PURPOSE: To characterize parental practices of informing children of risk for Huntington disease (HD), and to understand the attitudes of parents concerning childhood participation in HD research. METHODS: An anonymous Internet survey was accessed by individuals of HD families. The survey probed for data regarding individual risk for HD, as well as when or if children had been informed of the disease. Respondents expressed their attitudes concerning childhood participation in HD clinical research. RESULTS: Two hundred forty-nine individuals responded (approximately 80% female), and 84% had never participated in an HD clinical trial. Seventy-five percent of respondents were parents; nearly two thirds of them had provided some information about HD to their children. There was overwhelming support for affected, at-risk, and unaffected adults in terms of HD research participation, but there was a statistically significant disparity by gene status, with gene negative and symptomatic gene positive adults being more inclined to participate than at-risk or asymptomatic/gene positive adults. More than 50% of respondents supported childhood participation, but typically in late adolescence (15-18 years). Gene negative and symptomatic adults were statistically more likely to agree with childhood inclusion than at-risk or asymptomatic/gene positive adults. CONCLUSION: These results serve as pilot data for further investigations to address childhood participation in HD research. In addition, these findings will inform ongoing studies as to appropriate practices to undertake to include minors.

Nutritional vitamin D deficiency presenting as hemichorea.

The authors describe a pediatric patient with repaired hypoplastic left heart syndrome developing protein-losing enteropathy, hypocalcemia, vitamin D deficiency, and hemichorea. After correction of nutritional vitamin D deficiency with calcium and vitamin D supplementation, the chorea resolved. Hypoalbuminemia also improved after the correction of vitamin D deficiency without requiring albumin infusions. This report also raises the possible role of calcium or vitamin D in the intestinal loss of albumin in protein-losing enteropathy.

Physician Communication in Pediatric End-of-Life Care: A Simulation Study.

OBJECTIVE: The objective of this exploratory study is to describe communication between physicians and the actor parent of a standardized 8-year-old patient in respiratory distress who was nearing the end of life. METHODS: Thirteen pediatric emergency medicine and pediatric critical care fellows and attendings participated in a high-fidelity simulation to assess physician communication with an actor-parent. RESULTS: Fifteen percent of the participants decided not to initiate life-sustaining technology (intubation), and 23% of participants offered alternatives to life-sustaining care, such as comfort measures. Although 92% of the participants initiated an end-of-life conversation, the quality of that discussion varied widely. CONCLUSION: Findings indicate that effective physician-parent communication may not consistently occur in cases involving the treatment of pediatric patients at the end of life in emergency and critical care units. PRACTICE IMPLICATIONS: The findings in this study, particularly that physician-parent end-of-life communication is often unclear and that alternatives to life-sustaining technology are often not offered, suggest that physicians need more training in both communication and end-of-life care.

Chorea as manifestation of epilepsia partialis continua in a child.

The authors present a case of a child with epilepsy who developed choreoathetotic movements coinciding with the development of epilepsia partialis continua. His abnormal movements and seizures resolved after successful management of his epilepsia partialis continua with intravenous immunoglobulin and steroid therapy. The authors propose that the chorea was an unusual manifestation of epilepsia partialis continua.

Comprehensive behavioral intervention to improve occupational performance in children with Tourette disorder.

OBJECTIVE. We evaluated the efficacy of a comprehensive behavioral intervention for tics (CBIT) program to reduce tic severity and improve occupational performance in children with tic disorder using a one-group pretest-posttest design. METHOD. Thirty children with tic disorder completed an eight-session CBIT program. The program focused on habit reversal, relaxation training, and function-based approaches to address how the environment and social situations (antecedents and consequences) sustain or influence tic severity. RESULTS. We observed significant reduction in the number of tics and improvement in scores on the Parent Tic Questionnaire, Subjective Units of Distress Scale, and Child Occupational Self Assessment after CBIT compared with scores at baseline. CONCLUSION. Findings provided support that CBIT reduced the number of tic expressions, tic severity, and level of distress associated with tic and improved these children's self-perception of their competence in and importance of performing everyday activities (i.e., occupational performance).

Streptococcal upper respiratory tract infections and exacerbations of tic and obsessive-compulsive symptoms: a prospective longitudinal study.

OBJECTIVE: The objective of this blinded, prospective, longitudinal study was to determine whether new group A ß hemolytic streptococcal (GABHS) infections are temporally associated with exacerbations of tic or obsessive-compulsive (OC) symptoms in children who met published criteria for pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). A group of children with Tourette syndrome and/or OC disorder without a PANDAS history served as the comparison (non-PANDAS) group. METHOD: Consecutive clinical ratings of tic and OC symptom severity were obtained for 31 PANDAS subjects and 53 non-PANDAS subjects. Clinical symptoms and laboratory values (throat cultures and streptococcal antibody titers) were evaluated at regular intervals during a 25-month period. Additional testing occurred at the time of any tic or OC symptom exacerbation. New GABHS infections were established by throat swab cultures and/or recent significant rise in streptococcal antibodies. Laboratory personnel were blinded to case or control status, clinical (exacerbation or not) condition, and clinical evaluators were blinded to the laboratory results. RESULTS: No group differences were observed in the number of clinical exacerbations or the number of newly diagnosed GABHS infections. On only six occasions of a total of 51 (12%), a newly diagnosed GABHS infection was followed, within 2 months, by an exacerbation of tic and/or OC symptoms. In every instance, this association occurred in the non-PANDAS group. CONCLUSIONS: This study provides no evidence for a temporal association between GABHS infections and tic/OC symptom exacerbations in children who meet the published PANDAS diagnostic criteria.

Tremor in childhood.

Tremor in childhood is not commonly described in the literature; but it is also likely underappreciated. The etiology of childhood tremor encompasses a wide variety of pathologic processes. Tremor may occur in isolation, or in association with other neurologic findings or systemic disorders. This article aims to provide an overview of tremorogenic mechanisms with respect to neuroanatomy and neurophysiology, particularly as they relate to children. Classification of tremors, diagnostic entities in childhood, and treatment will also be discussed. With improved recognition and characterization of childhood tremors, we may gain a better understanding of the pathophysiology of the disease and determine more age-appropriate treatment strategies.

Association between male gender and pediatric essential tremor.

Approximately 5% of new essential tremor (ET) cases arise during childhood. The goal of the current report was to examine the possible association between male gender and pediatric ET, using data from 95 pediatric ET cases seen at three medical centers (two in the United States and one in Spain). The odds of ET in our sample of cases were threefold higher in boys compared to girls. Whether this association between male gender and pediatric ET represents a selection bias or a true gender-mediated biological difference in disease expression is not known, although some data support the latter possibility.

Sequence variants in SLITRK1 are associated with Tourette's syndrome.

Tourette's syndrome (TS) is a genetically influenced developmental neuropsychiatric disorder characterized by chronic vocal and motor tics. We studied Slit and Trk-like 1 (SLITRK1) as a candidate gene on chromosome 13q31.1 because of its proximity to a de novo chromosomal inversion in a child with TS. Among 174 unrelated probands, we identified a frameshift mutation and two independent occurrences of the identical variant in the binding site for microRNA hsa-miR-189. These variants were absent from 3600 control chromosomes. SLITRK1 mRNA and hsa-miR-189 showed an overlapping expression pattern in brain regions previously implicated in TS. Wild-type SLITRK1, but not the frameshift mutant, enhanced dendritic growth in primary neuronal cultures. Collectively, these findings support the association of rare SLITRK1 sequence variants with TS.

Paroxysmal Dyskinesias in Children.

Paroxysmal dyskinesias are rare movement disorders. The onset of paroxysmal dyskinesias in childhood are typically idiopathic (sporadic or familial), whereas those in adulthood are usually secondary to an identifiable cause. Paroxysmal dyskinesias are classified according to precipitating factors, and these include paroxysmal kinesigenic dyskinesia, paroxysmal nonkinesigenic dyskinesia, paroxysmal exertion-induced dyskinesia, and paroxysmal hypnogenic dyskinesia. The pathophysiology remains unknown; however, there is increasing evidence that channelopathies may play a role, which explains the response to anticonvulsant medications in certain kindreds. Pharmacologic treatment with anticonvulsant medications, clonazepam, tetrabenazine, trihexyphenidyl, or levodopa is reviewed herewith. Paroxysmal dyskinesias go by many names, but a rational classification does exist. Of those that respond to medications, the majority of paroxysmal dyskenesias respond to anticonvulsant medications. Channelopathies have been implemented as a cause in paroxysmal dyskinesias.

Exclusive lower extremity mirror movements and diastematomyelia.

Mirror movements usually seen in the Klippel-Feil syndrome are most commonly appreciated in the upper extremities. Lower extremity involvement is seen rarely and when observed, is found in conjunction with upper extremity mirror movements. We report what we believe to be the first case of mirror movements found exclusively in the lower extremities in a female patient presenting with tethered cord syndrome. Our hopes are that this report will help elucidate mechanisms involved with these anomalous movements, as currently there is no commonly accepted etiology.

Ophthalmologic involvement in the syndrome of headache, neurologic deficits, and cerebrospinal fluid lymphocytosis.

PURPOSE: To emphasize that papilledema and other ophthalmic manifestations may occur in the syndrome of headache, neurologic deficits, and cerebrospinal fluid lymphocytosis (HaNDL). DESIGN: Two interventional case reports. METHODS: Two patients were seen with ophthalmologic findings, including decreased vision, papilledema, sixth nerve palsy, and a variety of neurologic deficits. Each underwent cerebrospinal fluid analysis and intracranial pressure measurement by spinal tap and neuroimaging studies to confirm the diagnosis of HaNDL. RESULTS: Both patients received acetazolamide to lower intracranial pressure. The first patient had complete resolution of signs and symptoms. The second, who was also given systemic corticosteroids, was left with diminished visual acuity in the right eye with nasal visual field loss and optic atrophy. CONCLUSIONS: The diagnosis of HaNDL is one of exclusion, which must be made in conjunction with a neurologist. HaNDL may be accompanied by elevated intracranial pressure and papilledema. As in other disorders causing papilledema, these patients may have permanent visual sequelae. Recognition by the ophthalmologist of this rarely reported syndrome will facilitate prompt patient diagnosis and treatment.