Clinical and genetic spectrum of RNF216-related disorder: a new case and literature review

BACKGROUND

Cases of RNF216-related disorder have been reported sporadically. However, the clinical and genetic spectrum of this disorder has not been fully studied.

METHODS

We identified an individual with a novel causative RNF216 variant in our institution and reviewed all individuals with causative RNF216 variants in previous reports. The clinical and genetic features of all the described individuals were analysed and summarised.

RESULTS

Twenty-four individuals from 17 families with causative RNF216 variants were identified. The mean age at the onset of neurological symptoms was 29.2 years (range 18-49 years). Ataxia (57%) was the most frequent initial symptoms in individuals under 30 years old, while chorea (63%) was the most frequent initial symptom in individuals over 30 years old. Over 90% of individuals presented with cognitive impairment and hypogonadotropic hypogonadism throughout the disease. White matter lesions (96%) and cerebellar atrophy (92%) were the most common imaging findings. Twenty pathogenic variants in RNF216 were detected. The variants in 12 (71%) families were inherited in a monogenic recessive pattern, whereas the variants in 5 (29%) were inherited in a digenic pattern by acting with variants in other genes. The majority of the RNF216 variants (85%) resulted in amino acid changes or the truncation of the 'RING between RING' (RBR) domain or C-terminal extension.

CONCLUSION

RNF216-related disorder is an inherited neuroendocrine disease characterised by cerebellar ataxia, chorea, cognitive impairment and hypogonadotropic hypogonadism. Most causative variants in patients with RNF216-related disorder influence the RBR domain or C-terminal extension of RNF216.

Genome-wide screening identifies Trim33 as an essential regulator of dendritic cell differentiation

The development of dendritic cells (DCs), including antigen-presenting conventional DCs (cDCs) and cytokine-producing plasmacytoid DCs (pDCs), is controlled by the growth factor Flt3 ligand (Flt3L) and its receptor Flt3. We genetically dissected Flt3L-driven DC differentiation using CRISPR-Cas9-based screening. Genome-wide screening identified multiple regulators of DC differentiation including subunits of TSC and GATOR1 complexes, which restricted progenitor growth but enabled DC differentiation by inhibiting mTOR signaling. An orthogonal screen identified the transcriptional repressor Trim33 (TIF-1γ) as a regulator of DC differentiation. Conditional targeting in vivo revealed an essential role of Trim33 in the development of all DCs, but not of monocytes or granulocytes. In particular, deletion of Trim33 caused rapid loss of DC progenitors, pDCs, and the cross-presenting cDC1 subset. Trim33-deficient Flt3+ progenitors up-regulated pro-inflammatory and macrophage-specific genes but failed to induce the DC differentiation program. Collectively, these data elucidate mechanisms that control Flt3L-driven differentiation of the entire DC lineage and identify Trim33 as its essential regulator.

Innovative prognostic modeling in ESCC: leveraging scRNA-seq and bulk-RNA for dendritic cell heterogeneity analysis

Background

Globally, esophageal squamous cell carcinoma (ESCC) stands out as a common cancer type, characterized by its notably high rates of occurrence and mortality. Recent advancements in treatment methods, including immunotherapy, have shown promise, yet the prognosis remains poor. In the context of tumor development and treatment outcomes, the tumor microenvironment (TME), especially the function of dendritic cells (DCs), is significantly influential. Our study aims to delve deeper into the heterogeneity of DCs in ESCC using single-cell RNA sequencing (scRNA-seq) and bulk RNA analysis.

Methods

In the scRNA-seq analysis, we utilized the SCP package for result visualization and functional enrichment analysis of cell subpopulations. CellChat was employed to identify potential oncogenic mechanisms in DCs, while Monocle 2 traced the evolutionary trajectory of the three DC subtypes. CopyKAT assessed the benign or malignant nature of cells, and SCENIC conducted transcription factor regulatory network analysis, offering a preliminary exploration of DC heterogeneity. In Bulk-RNA analysis, we constructed a prognostic model for ESCC prognosis and immunotherapy response, based on DC marker genes. This model was validated through quantitative PCR (qPCR) and immunohistochemistry (IHC), confirming the gene expression levels.

Results

In this study, through intercellular communication analysis, we identified GALECTIN and MHC-I signaling pathways as potential oncogenic mechanisms within dendritic cells. We categorized DCs into three subtypes: plasmacytoid (pDC), conventional (cDC), and tolerogenic (tDC). Our findings revealed that pDCs exhibited an increased proportion of cells in the G2/M and S phases, indicating enhanced cellular activity. Pseudotime trajectory analysis demonstrated that cDCs were in early stages of differentiation, whereas tDCs were in more advanced stages, with pDCs distributed across both early and late differentiation phases. Prognostic analysis highlighted a significant correlation between pDCs and tDCs with the prognosis of ESCC (P< 0.05), while no significant correlation was observed between cDCs and ESCC prognosis (P = 0.31). The analysis of cell malignancy showed the lowest proportion of malignant cells in cDCs (17%), followed by pDCs (29%), and the highest in tDCs (48%), with these results being statistically significant (P< 0.05). We developed a robust ESCC prognostic model based on marker genes of pDCs and tDCs in the GSE53624 cohort (n = 119), which was validated in the TCGA-ESCC cohort (n = 139) and the IMvigor210 immunotherapy cohort (n = 298) (P< 0.05). Additionally, we supplemented the study with a novel nomogram that integrates clinical features and risk assessments. Finally, the expression levels of genes involved in the model were validated using qPCR (n = 8) and IHC (n = 16), thereby confirming the accuracy of our analysis.

Conclusion

This study enhances the understanding of dendritic cell heterogeneity in ESCC and its impact on patient prognosis. The insights gained from scRNA-seq and Bulk-RNA analysis contribute to the development of novel biomarkers and therapeutic targets. Our prognostic models based on DC-related gene signatures hold promise for improving ESCC patient stratification and guiding treatment decisions.

Childhood-onset Huntignton´s disease. A rare presentation

INTRODUCTION

Huntington's disease (HD) is a rare autosomal dominant disease caused by the expansion of CAG triplets in the gene that encodes huntingtin. There are earlier symptoms' onset in offspring due to the phenomenon of anticipation. The clinical features of childhood-onset HD, before age 10 years, differs from adult-onset form. It is characterized by motor impairment, behavioral difficulties and delay or regression in areas of development; while chorea is rarely seen. In this case we describe clinical aspects of a patient with childhood-onset Huntington's disease.

CASE REPORT

A 5-year-old girl with a family history of HD and typical development up to 3 years of age. She progressively acquired language impairment with skills that were below her age in expressive and receptive areas, without deficits in pragmatic and social skills. Regarding motor skills, she manifested instability at walking and standing, with rigidity, dystonia and choreic movements. Atrophy of the basal ganglia was evident on MRI, EEG was normal, and molecular confirmation of CAG triplet revealed repeat length of 51 copies.

CONCLUSION

Childhood-onset HD differs from adult-form´s clinical manifestations. It should be considered in patients with progressive motor and cognitive impairment. Due to family inheritance, it is important to carefully examine family history and take it into account even without relatives affected, considering the anticipation phenomenon.

Identifying and verifying Huntington's disease subtypes: Clinical features, neuroimaging, and cytokine changes

AIMS

Huntington's disease (HD) is a progressive neurodegenerative disorder with heterogeneous clinical manifestations. Identifying distinct clinical clusters and their relevant biomarkers could elucidate the underlying disease pathophysiology.

METHODS

Following the Enroll-HD program initiated in 2018.09, we have recruited 104 HD patients (including 21 premanifest) and 31 health controls at Beijing Tiantan Hospital. Principal components analysis and k-means cluster analysis were performed to determine HD clusters. Chi-square test, one-way ANOVA, and covariance were used to identify features among these clusters. Furthermore, plasma cytokines levels and brain structural imaging were used as biomarkers to delineate the clinical features of each cluster.

RESULTS

Three clusters were identified. Cluster 1 demonstrated the most severe motor and nonmotor symptoms except for chorea, the lowest whole brain volume, the plasma levels of IL-2 were higher and significantly associated with cluster 1. Cluster 2 was characterized with the most severe chorea and the largest pallidum volume. Cluster 3 had the most benign motor symptoms but moderate psychiatric problems.

CONCLUSION

We have identified three HD clusters via clinical manifestations with distinct biomarkers. Our data shed light on better understanding about the pathophysiology of HD.

Rethinking Movement Disorders

At present, clinical practice and research in movement disorders (MDs) focus on the "normalization" of altered movements. In this review, rather than concentrating on problems and burdens people with MDs undoubtedly have, we highlight their hidden potentials. Starting with current definitions of Parkinson's disease (PD), dystonia, chorea, and tics, we outline that solely conceiving these phenomena as signs of dysfunction falls short of their complex nature comprising both problems and potentials. Such potentials can be traced and understood in light of well-established cognitive neuroscience frameworks, particularly ideomotor principles, and their influential modern derivatives. Using these frameworks, the wealth of data on altered perception-action integration in the different MDs can be explained and systematized using the mechanism-oriented concept of perception-action binding. According to this concept, MDs can be understood as phenomena requiring and fostering flexible modifications of perception-action associations. Consequently, although conceived as being caught in a (trough) state of deficits, given their high flexibility, people with MDs also have high potential to switch to (adaptive) peak activity that can be conceptualized as hidden potentials. Currently, clinical practice and research in MDs are concerned with deficits and thus the "deep and wide troughs," whereas "scattered narrow peaks" reflecting hidden potentials are neglected. To better delineate and utilize the latter to alleviate the burden of affected people, and destigmatize their conditions, we suggest some measures, including computational modeling combined with neurophysiological methods and tailored treatment. © 2024 International Parkinson and Movement Disorder Society.

Clinical Spectrum, Treatment and Outcome of Children with Autoimmune Encephalitis

OBJECTIVE

To assess the clinical spectrum, treatment, and outcome of children with autoimmune encephalitis (AE).

STUDY DESIGN

Descriptive study. Place and Duration of the Study: Department of Paediatrics, The Aga Khan University Hospital, Karachi, Pakistan, from January 2017 to December 2021.

METHODOLOGY

Medical records of children with a diagnosis of AE were reviewed for clinical features, treatment details, and outcomes. Outcome was defined as good (0-2) or poor (3-6) based on a modified Rankin Scale (mRS) score at 3-month follow-up. Descriptive statistics were reported and logistic regression was used to assess the prognostic factors associated with outcome.

RESULTS

Thirty-three patients were identified with AE. Thirteen (39.3%) were antibody positive. Anti-N-methyl-D-aspartate receptor (NMDAR) antibody was seen in 92% of positive cases. Behavioural abnormalities (87.8%), seizures (81.8%), movement disorders (66.6%), psychiatric symptoms (63.6%), and mutism (33.3%) were the prominent symptoms. Thirty (91%) patients received first-line immunotherapy. Good outcome was seen in 14 (48.2%) patients. Univariable analysis showed that the odds of having poor outcome were 2.5 (95% confidence interval [CI] 0.37-16.88, p=0.34) in patients with chorea. In addition, an elevated cerebrospinal fluid (CSF) protein had an odds ratio (OR) of 8.6 (CI 0.88-84.83, p=0.064) and positive CSF antibodies had an OR of 3.7 (CI 0.79-17.72, p=0.095) for a poor outcome. Mortality was seen in 4 (12.1%) patients.

CONCLUSION

A very low threshold is needed for the diagnosis of AE in children presenting with behavioural symptoms and chorea. Although the odds for poor prognosis were higher in patients with chorea, elevated CSF protein and positive CSF antibodies, the p-value did not come out significant.

KEY WORDS

Autoimmune encephalitis, Antibodies, NMDAR, Immunotherapies, mRS score, Outcome.

Transient Hemichorea-hemiballism Induced by a Combination of Postprandial Hypotension and Severe Stenosis of the Innominate Artery Concomitant with Left Carotid Occlusion

Hemichorea-hemiballism (HCHB) due to transient ischemic attacks (TIAs) is rare. An 83-year-old woman had repeated episodes of right-sided HCHB for 3 months. Magnetic resonance (MR) angiography demonstrated occlusion of the left carotid and middle cerebral arteries and severe stenosis of the innominate artery, and 24-hour ambulatory blood pressure monitoring showed a blood pressure decrease of >20 mmHg after each meal. We speculated that HCHB developed as TIAs due to hemodynamic failure in the left cerebral hemisphere, caused by a combination of severe stenosis of the innominate artery concomitant with occlusion of the left carotid and middle cerebral arteries as well as postprandial hypotension.

BK Channelopathies and KCNMA1-Linked Disease Models

Novel KCNMA1 variants, encoding the BK K+ channel, are associated with a debilitating dyskinesia and epilepsy syndrome. Neurodevelopmental delay, cognitive disability, and brain and structural malformations are also diagnosed at lower incidence. More than half of affected individuals present with a rare negative episodic motor disorder, paroxysmal nonkinesigenic dyskinesia (PNKD3). The mechanistic relationship of PNKD3 to epilepsy and the broader spectrum of KCNMA1-associated symptomology is unknown. This review summarizes patient-associated KCNMA1 variants within the BK channel structure, functional classifications, genotype-phenotype associations, disease models, and treatment. Patient and transgenic animal data suggest delineation of gain-of-function (GOF) and loss-of-function KCNMA1 neurogenetic disease, validating two heterozygous alleles encoding GOF BK channels (D434G and N999S) as causing seizure and PNKD3. This discovery led to a variant-defined therapeutic approach for PNKD3, providing initial insight into the neurological basis. A comprehensive clinical definition of monogenic KCNMA1-linked disease and the neuronal mechanisms currently remain priorities for continued investigation.

Evaluating motor progression of juvenile-onset Huntington's Disease: An Enroll-HD analysis

INTRODUCTION

Juvenile-onset Huntington's disease (JOHD) is characterized by a unique motor phenotype relative to patients with adult-onset Huntington's Disease (AOHD). This study characterized motor progression of JOHD to propose improved outcome measures for this group.

METHODS

We used linear mixed effect regression models to compare progression of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score (TMS) and the chorea score between patients with JOHD and AOHD. We then evaluated all 31 subscales that make up the UHDRS over time within patients with JOHD to identify measures that may be used to track motor progression most reliably.

RESULTS

The JOHD cohort had faster TMS progression compared to AOHD (p = 0.006) but no group difference in the rate of change of chorea. Patients with JOHD did not show significant change in any of the chorea subscales. The subscales that changed most reliably over time amongst patients with JOHD were dysarthria, upper extremity dystonia, tandem walking, gait, bilateral pronate/supinate, bilateral finger-tapping, and tongue protrusion. When these subscales were summed, they progressed at a faster rate (7.07%, 95% CI [5.96-8.18]) than the TMS (4.92%, 95% CI [3.95-5.89]).

CONCLUSION

While the TMS changes at a significant rate in JOHD subjects, not all subscales that make up the TMS accurately represent the unique motor features of JOHD. A JOHD-specific scale performed better at tracking motor progression relative to the TMS. This scale may improve clinical care for patients with JOHD and allow for the development of more efficient clinical trials.

Emerging Subspecialties: Pediatric Movement Disorders Neurology

Pediatric movement disorders (PMD) neurologists care for infants, children, and adolescents with conditions that disrupt typical movement; serving as important subspecialist child neurologists in both academic and private practice settings. In contrast to adult movement disorders neurologists whose "bread and butter" is hypokinetic Parkinson disease, PMD subspecialty practice is often dominated by hyperkinetic movement disorders including tics, dystonia, chorea, tremor, and myoclonus. PMD neurology practice intersects with a variety of subspecialties, including neonatology, developmental pediatrics, rehabilitation medicine, epilepsy, child & adolescent psychiatry, psychology, orthopedics, genetics & metabolism, and neurosurgery. Over the past several decades, significant advancements in the PMD field have included operationalizing definitions for distinct movement disorders, recognizing the spectrum of clinical phenotypes, expanding research on genetic and neuroimmunologic causes of movement disorders, and advancing available treatments. Subspecialty training in PMD provides trainees with advanced clinical, diagnostic, procedural, and management skills that reflect the complexities of contemporary practice. The child neurologist who is fascinated by the intricacies of child motor development, appreciates the power of observation skills coupled with a thoughtful physical examination, and is excited by the challenge of the unknown may be well-suited to a career as a PMD specialist.

A Critical Appraisal of the Whack-a-Mole and Swivel Chair Signs in the Diagnosis of Functional Movement Disorders

BACKGROUND

The demonstration of positive signs during neurological examination is a cornerstone of the diagnosis of functional movement disorders, however, the available data supporting the diagnostic value of some of these signs is limited.

OBJECTIVES

To determine the diagnostic value (sensitivity and specificity) of the "whack-a-mole" (WAM) and "swivel chair" (SC) tests in patients with functional movement disorders (FMD).

METHODS

We enrolled patients with functional and organic movements in the WAM test if they exhibited tremor, dystonia, myoclonus, chorea, or tics. For the SC test, patients with a gait disorder as their primary impairment were recruited. Two blinded movement disorder specialists rated the presence of these signs in edited videos.

RESULTS

Inclusion criteria were met by 42 patients with FMD and 65 patients with organic movement disorders. Both tests demonstrated high specificity (means, 78% and 96%), but their sensitivity was low (means, 52% and 37%). Interobserver agreement for the WAM sign was 0.77 in the FMD group, against 0.28 in patients with organic movement disorders, whereas Movement Disorders Clinical Practice for Review Only for the SC sign was 0.69 in both groups.

CONCLUSIONS

The present study indicates that physicians must be cautious in the application and interpretation of these clinical signs in the diagnosis of functional movement disorders, and they should be carefully considered and used as necessary.

Movement disorders associated with pediatric encephalitis

New onset movement disorders are a common clinical problem in pediatric neurology and can be infectious, inflammatory, metabolic, or functional in origin. Encephalitis is one of the more important causes of new onset movement disorders, and movement disorders are a common feature (~25%) of all encephalitis. However, all encephalitides are not the same, and movement disorders are a key diagnostic feature that can help the clinician identify the etiology of the encephalitis, and therefore appropriate treatment is required. Movement disorders are a characteristic feature of autoimmune encephalitis such as anti-NMDAR encephalitis, herpes simplex virus encephalitis-induced autoimmune encephalitis, and basal ganglia encephalitis. Other rarer autoantibody-associated encephalitis syndromes with movement disorder associations include encephalitis associated with glycine receptor, DPPX, and neurexin-3 alpha autoantibodies. In addition, movement disorders can accompany acute disseminated encephalomyelitis with and without myelin oligodendrocyte glycoprotein antibodies. Extremely important infectious encephalitides that have characteristic movement disorder associations include Japanese encephalitis, dengue fever, West Nile virus, subacute sclerosing panencephalitis (SSPE), and SARS-CoV-2 (COVID-19). This chapter discusses how specific movement disorder phenomenology can aid clinician diagnostic suspicion, such as stereotypy, perseveration, and catatonia in anti-NMDAR encephalitis, dystonia-Parkinsonism in basal ganglia encephalitis, and myoclonus in SSPE. In addition, the chapter discusses how the age of the patients can influence the movement disorder phenomenology, such as in anti-NMDAR encephalitis where chorea is typical in young children, even though catatonia and akinesia is more common in adolescents and adults.

The Potential Immunomodulatory Effect of Bifidobacterium longum subsp. longum BB536 on Healthy Adults through Plasmacytoid Dendritic Cell Activation in the Peripheral Blood

The interaction between the gut microbiota and the host can influence the host's immune system. Bifidobacterium, a commensal genus of gut bacteria, seems to have positive effects on host health. Our previous clinical research showed that B. longum subsp. longum BB536 enhanced innate and adaptive immune responses in elderly individuals with a lower grade of immunity, but the immunomodulatory mechanism is still unclear. In this study, dendritic cell (DC) surface markers in peripheral blood mononuclear cells isolated from healthy individuals were evaluated through coculture with heat-killed BB536. DC markers, innate immune activity and cytokine levels in plasma were also evaluated by a randomized, double-blind, placebo-controlled, parallel-group study (UMIN000045564) with 4 weeks of continuous live BB536 intake. BB536 significantly increased the expression of CD86 and HLA-DR on plasmacytoid DCs (pDCs) in vitro. Compared to placebo (n = 48), a significant increase in the expression of CD86 on peripheral pDCs was detected at week 4 of live BB536 intake (n = 49; 1 × 1010 CFU/day). Furthermore, coculture with hk-BB536 significantly increased the IFNγ expression level and demonstrated trends of increased IFNα1 and IFNβ expression. These findings suggest that consumption of BB536 has potential immunomodulatory effects on healthy individuals through the activation of peripheral pDCs.

Brazilian autoimmune encephalitis network (BrAIN): antibody profile and clinical characteristics from a multicenter study

Background

The frequency of antibodies in autoimmune encephalitis (AIE) may vary in different populations, however, data from developing countries are lacking. To describe the clinical profile of AIE in Brazil, and to evaluate seasonality and predictors of AIE in adult and pediatric patients.

Methods

We evaluated patients with possible AIE from 17 centers of the Brazilian Autoimmune Encephalitis Network (BrAIN) between 2018 and 2022. CSF and serum were tested with TBAs and CBAs. Data on clinical presentation, complementary investigation, and treatment were compiled. Seasonality and predictors of AIE in adult and pediatric populations were analyzed.

Results

Of the 564 patients, 145 (25.7%) were confirmed as seropositive, 69 (12.23%) were seronegative according to Graus, and 58% received immunotherapy. The median delay to diagnosis confirmation was 5.97 ± 10.3 months. No seasonality variation was observed after 55 months of enrolment. The following antibodies were found: anti-NMDAR (n=79, 54%), anti-MOG (n=14, 9%), anti-LGI1(n=12, 8%), anti-GAD (n=11, 7%), anti-GlyR (n=7, 4%), anti-Caspr2 (n=6, 4%), anti-AMPAR (n=4, 2%), anti-GABA-BR (n=4, 2%), anti-GABA-AR (n=2, 1%), anti-IgLON5 (n=1, 1%), and others (n=5, 3%). Predictors of seropositive AIE in the pediatric population (n=42) were decreased level of consciousness (p=0.04), and chorea (p=0.002). Among adults (n=103), predictors of seropositive AIE were movement disorders (p=0.0001), seizures (p=0.0001), autonomic instability (p=0.026), and memory impairment (p=0.001).

Conclusion

Most common antibodies in Brazilian patients are anti-NMDAR, followed by anti-MOG and anti-LGI1. Only 26% of the possible AIE patients harbor antibodies, and 12% were seronegative AIE. Patients had a 6-month delay in diagnosis and no seasonality was found. Findings highlight the barriers to treating AIE in developing countries and indicate an opportunity for cost-effect analysis. In this scenario, some clinical manifestations help predict seropositive AIE such as decreased level of consciousness, chorea, and dystonia among children, and movement disorders and memory impairment among adults.

Investigating Neuron Degeneration in Huntington's Disease Using RNA-Seq Based Transcriptome Study

Huntington's disease (HD) is a progressive neurodegenerative disorder caused due to a CAG repeat expansion in the huntingtin (HTT) gene. The primary symptoms of HD include motor dysfunction such as chorea, dystonia, and involuntary movements. The primary motor cortex (BA4) is the key brain region responsible for executing motor/movement activities. Investigating patient and control samples from the BA4 region will provide a deeper understanding of the genes responsible for neuron degeneration and help to identify potential markers. Previous studies have focused on overall differential gene expression and associated biological functions. In this study, we illustrate the relationship between variants and differentially expressed genes/transcripts. We identified variants and their associated genes along with the quantification of genes and transcripts. We also predicted the effect of variants on various regulatory activities and found that many variants are regulating gene expression. Variants affecting miRNA and its targets are also highlighted in our study. Co-expression network studies revealed the role of novel genes. Function interaction network analysis unveiled the importance of genes involved in vesicle-mediated transport. From this unified approach, we propose that genes expressed in immune cells are crucial for reducing neuron death in HD.

Altered brain connectivity in hyperkinetic movement disorders: A review of resting-state fMRI

BACKGROUND

Hyperkinetic movement disorders (HMD) manifest as abnormal and uncontrollable movements. Despite reported involvement of several neural circuits, exact connectivity profiles remain elusive.

OBJECTIVES

Providing a comprehensive literature review of resting-state brain connectivity alterations using resting-state fMRI (rs-fMRI). We additionally discuss alterations from the perspective of brain networks, as well as correlations between connectivity and clinical measures.

METHODS

A systematic review was performed according to PRISMA guidelines and searching PubMed until October 2022. Rs-fMRI studies addressing ataxia, chorea, dystonia, myoclonus, tics, tremor, and functional movement disorders (FMD) were included. The standardized mean difference was used to summarize findings per region in the Automated Anatomical Labeling atlas for each phenotype. Furthermore, the activation likelihood estimation meta-analytic method was used to analyze convergence of significant between-group differences per phenotype. Finally, we conducted hierarchical cluster analysis to provide additional insights into commonalities and differences across HMD phenotypes.

RESULTS

Most articles concerned tremor (51), followed by dystonia (46), tics (19), chorea (12), myoclonus (11), FMD (11), and ataxia (8). Altered resting-state connectivity was found in several brain regions: in ataxia mainly cerebellar areas; for chorea, the caudate nucleus; for dystonia, sensorimotor and basal ganglia regions; for myoclonus, the thalamus and cingulate cortex; in tics, the basal ganglia, cerebellum, insula, and frontal cortex; for tremor, the cerebello-thalamo-cortical circuit; finally, in FMD, frontal, parietal, and cerebellar regions. Both decreased and increased connectivity were found for all HMD. Significant spatial convergence was found for dystonia, FMD, myoclonus, and tremor. Correlations between clinical measures and resting-state connectivity were frequently described.

CONCLUSION

Key brain regions contributing to functional connectivity changes across HMD often overlap. Possible increases and decreases of functional connections of a specific region emphasize that HMD should be viewed as a network disorder. Despite the complex interplay of physiological and methodological factors, this review serves to gain insight in brain connectivity profiles across HMD phenotypes.

Prevalence of diabetic striatopathy and predictive role of glycated hemoglobin level

Background

Diabetic striatopathy is defined as a state of hyperglycemia associated with chorea/ballism, striatal hyperdensity at CT, or hyperintensity at T1-weighted MRI. It is considered a rare complication of uncontrolled diabetes but prevalence data are scarce.

Objectives

Characterize diabetic striatopathy prevalence in the population afferent to the largest teaching hospital in Genova (Liguria, Italy) and investigate the role of glycated hemoglobin level in predicting the risk.

Methods

Data were retrospectively obtained from general population undergoing blood sampling for glycated hemoglobin and resulting with HbA1c values ≥ 8%, from January 2014 to June 2017. Brain neuroimaging of those who underwent at least a brain CT or MRI was examined in search of findings compatible with diabetic striatopathy and clinical information was collected. Logistic regression was used to predict the risk of diabetic striatopathy based on age and HbA1c values.

Results

Subjects with uncontrolled diabetes were 4603. Brain neuroimaging was available in 1806 subjects and three patients with diabetic striatopathy were identified, all of them reporting choreic movements. The prevalence of hemichorea due to diabetic striatopathy was therefore 3 cases out of 1806 (0.16%) in our population. Hepatic and hypoxic encephalopathies were the conditions most frequently mimicking diabetic striatopathy. Odds ratio of diabetic striatopathy and HbA1c level was significantly correlated (p = 0.0009).

Conclusions

To the best of our knowledge, this study is the first to evaluate the prevalence of diabetic striatopathy in Italy. High HbA1c values may have a role in predicting diabetic striatopathy.

BK channel properties correlate with neurobehavioral severity in three KCNMA1-linked channelopathy mouse models

KCNMA1 forms the pore of BK K+ channels, which regulate neuronal and muscle excitability. Recently, genetic screening identified heterozygous KCNMA1 variants in a subset of patients with debilitating paroxysmal non-kinesigenic dyskinesia, presenting with or without epilepsy (PNKD3). However, the relevance of KCNMA1 mutations and the basis for clinical heterogeneity in PNKD3 has not been established. Here, we evaluate the relative severity of three KCNMA1 patient variants in BK channels, neurons, and mice. In heterologous cells, BKN999S and BKD434G channels displayed gain-of-function (GOF) properties, whereas BKH444Q channels showed loss-of-function (LOF) properties. The relative degree of channel activity was BKN999S > BKD434G>WT > BKH444Q. BK currents and action potential firing were increased, and seizure thresholds decreased, in Kcnma1N999S/WT and Kcnma1D434G/WT transgenic mice but not Kcnma1H444Q/WT mice. In a novel behavioral test for paroxysmal dyskinesia, the more severely affected Kcnma1N999S/WT mice became immobile after stress. This was abrogated by acute dextroamphetamine treatment, consistent with PNKD3-affected individuals. Homozygous Kcnma1D434G/D434G mice showed similar immobility, but in contrast, homozygous Kcnma1H444Q/H444Q mice displayed hyperkinetic behavior. These data establish the relative pathogenic potential of patient alleles as N999S>D434G>H444Q and validate Kcnma1N999S/WT mice as a model for PNKD3 with increased seizure propensity.

A case of brainlungthyroid syndrome

Brain-lung-thyroid syndrome is a rare autosomal dominant disorder. More than 100 cases have been reported worldwide, but few cases have been reported in China. In December 2018, a boy with brain-lung-thyroid syndrome, aged 3 years and 10 months, was admitted to Xiangya Hospital of Central South University due to repeated cough for more than 3 years. In infancy of the boy, psychomotor retardation, repeated cough, and hypothyroidism were found. Gene detection showed that there was c.927delc heterozygous variation in NKX2-1 gene (NM-001079668: exon3: c.927delC). The variation of this gene locus has not been reported in relevant literature so far, which indicates a new mutation. According to the above clinical manifestations and examination results, the boy was diagnosed as brain-lung-thyroid syndrome, which mainly characterized by nervous system disorders, accompanied by respiratory manifestations and hypothyroidism. The boy was treated with oral dopasehydrazine to relieve tremor and levothyroxine sodium tablets to relieve hypothyroidism. Anti-infection, atomization, rehabilitation training and other symptomatic supporting treatment were also administered. The boy's language and movement have improved, the thyroid hormone level is normal, and there are still repeated respiratory tract infections.

Clonal lineage tracing reveals shared origin of conventional and plasmacytoid dendritic cells

Developmental origins of dendritic cells (DCs) including conventional DCs (cDCs, comprising cDC1 and cDC2 subsets) and plasmacytoid DCs (pDCs) remain unclear. We studied DC development in unmanipulated adult mice using inducible lineage tracing combined with clonal DNA "barcoding" and single-cell transcriptome and phenotype analysis (CITE-seq). Inducible tracing of Cx3cr1+ hematopoietic progenitors in the bone marrow showed that they simultaneously produce all DC subsets including pDCs, cDC1s, and cDC2s. Clonal tracing of hematopoietic stem cells (HSCs) and of Cx3cr1+ progenitors revealed clone sharing between cDC1s and pDCs, but not between the two cDC subsets or between pDCs and B cells. Accordingly, CITE-seq analyses of differentiating HSCs and Cx3cr1+ progenitors identified progressive stages of pDC development including Cx3cr1+ Ly-6D+ pro-pDCs that were distinct from lymphoid progenitors. These results reveal the shared origin of pDCs and cDCs and suggest a revised scheme of DC development whereby pDCs share clonal relationship with cDC1s.

[Brain-lung-thyroid syndrome in a newborn with deletion 14q12-q21.1]

INTRODUCTION

In newborns with respiratory failure and interstitial lung disease, it should be approached as chILD (Childhood Interstitial Lung Disease) syndrome to rule out alterations in surfactant metabolism and brain-lung-thyroid syndrome caused by pathogenic variants in the NKX2-1 gene.

OBJECTIVE

To pre sent a newborn with chILD syndrome and a large deletion in chromosome 14q12-q21.1.

CLINICAL CASE

Newborn patient with respiratory distress since birth, chILD syndrome, and hypothyroidism, in which brain-lung-thyroid syndrome was suspected. He also presented seizures, minor and ma jor abnormalities on physical examination. Microarray analysis revealed a 14.7 Mb deletion in the chromosome 14q12-q21.1, which includes the NKX2-1 gene.

CONCLUSION

The brain-lung-thyroid syndrome should be considered in newborns with respiratory distress syndrome and diffuse lung disease (chILD syndrome), especially if they present hypotonia, choreoathetosis, or hypothyroidism. Diagnosis confirmation requires genetic analysis, even more, when there are other abnormalities not explained by the suspected syndrome.

Acute Movement Disorders in Childhood: A Cohort Study and Review of the Literature

OBJECTIVES

Acute movement disorders (AMD) are frequent in neurological and pediatric emergencies. Few studies analyzed AMD in children, none in Tunisia or other African country. The purpose of this study was to describe the peculiarities of AMD in a Tunisian pediatric population with a literature review.

METHODS

We conducted a retrospective descriptive study over 8 years including 80 children (sex ratio, 1.05; mean age of onset, 4.8 years) with AMD, followed in tertiary referral Child Neurology Department in North Tunisia.

RESULTS

Acute movement disorders were mainly hyperkinetic (n = 67 with dystonia (n = 33; mostly due to inherited metabolic diseases (IMD) in 11; with status epilepticus in 10 children), chorea (n = 14; with Sydenham chorea in 5); myoclonus (n = 14; mostly with opsoclonus-myoclonus syndrome in 10) and tremor (n = 6; of posttraumatic origin in half). Hypokinetic movement disorder (MD) included acute parkinsonism in 5 children of infectious (n = 3), postinfectious (n = 1, malaria) and posttraumatic origin (n = 1). Mixed MD, found in 8 children, were mainly due to IMD in half of them, and to familial lupus in two. Paroxysmal MDs were seen in 2 children, one with multiple sclerosis and one of idiopathic origin. Psychogenic MDs were found in 7 patients mainly of dystonic type. Management of AMD comprised symptomatic treatment according to the phenomenology of the MD and causative treatment depending on its etiology.

CONCLUSIONS

Our study illustrated the broad range of AMD in children and the wide spectrum of their etiologies. In our series, we described some exceptional findings and etiologies of AMD in children. These findings may denote a specific profile in of AMD in our country with predominant infectious, postinfectious, and IMD.

Deep brain stimulation in Huntington's disease: a literature review

BACKGROUND

Huntington's disease (HD) is a neurodegenerative disorder characterized by involuntary movements, cognitive decline, and behavioral changes. The complex constellation of clinical symptoms still makes the therapeutic management challenging. In the new era of functional neurosurgery, deep brain stimulation (DBS) may represent a promising therapeutic approach in selected HD patients.

METHODS

Articles describing the effect of DBS in patients affected by HD were selected from Medline and PubMed by the association of text words with MeSH terms as follows: "Deep brain stimulation," "DBS," and "HD," "Huntington's disease," and "Huntington." Details on repeat expansion, age at operation, target of operation, duration of follow-up, stimulation parameters, adverse events, and outcome measures were collected.

RESULTS

Twenty eligible studies, assessing 42 patients with HD, were identified. The effect of globus pallidus internus (GPi) DBS on Unified Huntington's Disease Rating Scale (UHDRS) total score revealed in 10 studies an improvement of total score from 5.4 to 34.5%, and in 4 studies, an increase of motor score from 3.8 to 97.8%. Bilateral GPi-DBS was reported to be effective in reducing Chorea subscore in all studies, with a mean percentage reduction from 21.4 to 73.6%.

CONCLUSIONS

HD patients with predominant choreic symptoms may be the best candidates for surgery, but the role of other clinical features and of disease progression should be elucidated. For this reason, there is a need for more reliable criteria that may guide the selection of HD patients suitable for DBS. Accordingly, further studies including functional outcomes as primary endpoints are needed.

On the hunt for a cure: A guide to Huntington disease

ABSTRACT

Huntington disease is a rare genetic disorder characterized by motor, cognitive, and psychiatric impairments. Although the typical patient has a positive family history and initially presents with chorea between ages 30 and 50 years, some patients do not have a typical presentation. Healthcare providers should know when to refer patients to neurology for testing for Huntington disease. The earlier the diagnosis is made, the earlier the patient and patient's family can receive education about the expected disease trajectory. A multidisciplinary approach is required to mitigate symptoms as the disease progresses. Although no cure exists, ongoing research is targeting genotypic abnormalities in hopes of finding a permanent treatment for Huntington disease.

[Recurrent psychotic symtoms over several years were caused by Huntington's disease]

Huntington disease (HD) is a progressive neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin gene. It is inherited in an autosomal dominant fashion with full penetrance. Around 15% of cases arise from spontaneous expansion of the CAG repeat. The clinical presentation includes involuntary movements (chorea) with dysarthria and dysphagia as well as cognitive and psychiatric symptoms and weight loss. The combination of these symptoms and signs should lead to further investigations regarding HD, even in absence of a known family history. Psychiatric and cognitive symptoms often manifest around 15 years before the motor disorder and the disease leads to premature death. HD is likely underdiagnosed as many individuals present with psychiatric and behavioral problems for a long time. No disease modifying treatment is available today but there are a number of clinical trials ongoing aiming at slowing the disease process. The successful progress of these trials will give urgency to correct diagnosis of HD.

The GRIA3 c.2477G > A Variant Causes an Exaggerated Startle Reflex, Chorea, and Multifocal Myoclonus

BACKGROUND

Hemizygous mutations in GRIA3 encoding the GluA3 subunit of the amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor are known to be associated with neurodevelopmental disorders, including intellectual disability, hypotonia, an autism spectrum disorder, sleep disturbances, and epilepsy in males.

OBJECTIVE

To describe a new and consistent phenotype in 4 affected male patients associated with an undescribed deleterious variant in GRIA3.

METHODS

We evaluated a large French family in which segregate a singular phenotype according to an apparent X-linked mode of inheritance. Molecular analyses using next generation sequencing and in vitro functional studies using 2-electrode voltage clamp recordings on Xenopus laevis oocytes and a β-lactamase reporter assay in transfected human embryonic kidney (HEK293) cells were performed.

RESULTS

In addition to mild intellectual disability and dysarthria, affected patients presented a tightly consistent early-onset movement disorder combining an exaggerated startle reflex with generalized chorea and multifocal myoclonus. The unreported GRIA3 missense variant c.2477G > A; p.(Gly826Asp) affecting the fourth transmembrane domain of the protein was identified in index patients and their unaffected mothers. Functional studies revealed that variant receptors show decreased current response evoked by agonist (ie, kainic acid and glutamate) and reduced expression on the cell surface in favor of pathogenicity by a loss-of-function mechanism.

CONCLUSIONS

Taken together, our results suggest that apart from known GRIA3-related disorders, an undescribed mutation-specific singular movement disorder does exist. We thus advocate considering GRIA3 mutations in the differential diagnosis of hyperekplexia and generalized chorea with myoclonus. © 2020 International Parkinson and Movement Disorder Society.

Hemichorea Secondary to Non-Ketotic Hyperglycemia as the Presenting Manifestation of Diabetes Mellitus

Nonketotic hyperglycemia is an unusual and rare cause of hemichorea. Hemichorea though rare may be the initial manifestation of diabetes mellitus. Correction of the hyperglycemia usually results in total resolution of the signs and symptoms. We present the case of a 71 yr old female, who presented with subacute onset of choreiform movement of left upper and lower extremities over 8 days. Her serum glucose level was 416 mg/dl and urine ketone bodies were absent. Computed tomography of brain showed right caudate nucleus and right lentiform nucleus hyperdensity suggesting hyperglycemia related hemichorea syndrome. Restoration of euglycemia along with treatment with haloperidol and tetrabenazine led to eventual resolution of all symptoms. So, nonketotic hyperglycemia should be kept as a differential diagnosis in a patient with hemichorea.

Fahr's Syndrome and Neuropsychiatric Symptoms: Differential Diagnosis in Neuropsychiatry

N/a.

Movement Disorder - A Rare Presentation of Diabetic Ketoacidosis

Diabetic ketoacidosis is a common acute complication of Diabetes Mellitus. Diabetic ketoacidosis is known to cause impaired consciousness due to the osmolar and acid base imbalance which in turn cause central nervous system involvement. Here we report a rare presentation of Diabetic ketoacidosis with movement disorder in form of hemichorea and facial tics. The movement disorder improved with treatment of ketosis.

Huntington's Chorea—Some Biochemical and Therapeutic Aspects

Huntington's Chorea presents us with a good “model” of brain disease in that we know the extent of the contribution of heredity, in contrast to a condition such as schizophrenia regarding which many authors (cf. Alanen, 1958) would be prepared to defend the concept of pseudo-heredity. Secondly the disease carries a fairly uniform prognosis, and finally it results in a distinctive disturbance of motor function which permits of some accuracy in diagnosis and some criterion for objective measurement.

What is new in tics, dystonia and chorea?

Movement disorders comprise hyperkinetic involuntary movements (eg tremor, myoclonus, tics, dystonia and chorea) and hypokinetic (parkinsonism) disorders. Tics are cardinal features of primary tic disorders encompassing Tourette syndrome (TS), but are also found in some neurodegenerative conditions and may be induced by psychoactive substances. The first line treatment for tics is pharmacological (mainly dopamine receptor blockers or alpha-2 adrenergic agonists) and behavioural. Dystonia and chorea syndromes are considerably heterogeneous in aetiology, and age at onset, body distribution of the movement disorder, accompanying neurological motor and non-motor features, and systemic manifestations are all important to reach a correct aetiological diagnosis. While symptomatic pharmacological treatment remains the mainstay of treatment for choreas, deep brain stimulation surgery has a well-defined place in the management of medically refractory dystonia.

Paroxysmal Kinesigenic Dyskinesia

We present a case of paroxysmal kinesigenic dyskinesia (PKD) in a 21 year old girl, with no family history of similar episodes. The episodes were short (lasting less than a minute), frequent, occurring 5 to 10 times a day, self-limiting dystonia of her right upper limb precipitated by sudden movement. She also had a past history of partial seizures with secondary generalization in her childhood. She responded to phenytoin, with cessation of events after 1 month of treatment. This case impresses upon the hypothesis stating the association between seizure activity and PKD probably due to a common foci of origin. Awareness of this condition is required as it is easily treatable but frequently misdiagnosed.

Visual inspection methods for cervical cancer prevention

The need for simple, cost-effective screening approaches for cervical cancer prevention in low-resource countries has led to the evaluation of visual screening with 3-5% acetic acid. The low reproducibility and wide variation in accuracy reflect the subjective nature of the test. Pooled sensitivity, specificity, positive and negative predictive values were 80%, 92%, 10% and 99%, respectively, for detecting cervical intraepithelial neoplasia grade 2 or worse lesions. Realistic sensitivity of a quality- assured single visual inspection with acetic acid is around 50%. A single round of visual inspection with acetic acid screening has been associated with a 25-35% reduction in cervical cancer incidence and the frequency of cervical intraepithelial neoplasia grade 2 or worse lesions in randomised-controlled trials. Despite all its limitations, implementing visual inspection with acetic acid screening in low-resource countries may provide a pragmatic approach to building up human resources and infrastructure that may facilitate the highly anticipated low-cost, rapid human papilloma virus testing in the near future.