Systematic review of drug therapy for chorea in NXK2-1-related disorders: Efficacy and safety evidence from case studies and series.

BACKGROUND: The NKX2-1-related disorders (NKX2-1-RD) is a rare disorder characterized by choreiform movements along with respiratory and endocrine abnormalities. The European Reference Network of Rare Neurological Disorders funded by the European Commission conducted a systematic review to assess drug treatment of chorea in NKX2-1-RD, aiming to provide clinical recommendations for its management. METHODS: A systematic pairwise review using various databases, including MEDLINE, Embase, Cochrane, CINAHL, and PsycInfo, was conducted. The review included patients diagnosed with chorea and NKX2-1-RD genetic diagnosis, drug therapy as intervention, no comparator, and outcomes of chorea improvement and adverse events. The methodological quality of the studies was assessed, and the study protocol was registered in PROSPERO. RESULTS: Of the 1417 studies examined, 28 studies met the selection criteria, consisting of 68 patients. The studies reported 22 different treatments for chorea, including carbidopa/levodopa, tetrabenazine, clonazepam, methylphenidate, carbamazepine, topiramate, trihexyphenidyl, haloperidol, propranolol, risperidone, and valproate. No clinical improvements were observed with carbidopa/levodopa, tetrabenazine, or clonazepam, and various adverse effects were reported. However, most patients treated with methylphenidate experienced improvements in chorea and reported only a few negative effects. The quality of evidence was determined to be low. CONCLUSIONS: The management of chorea in individuals with NKX2-1-RD presents significant heterogeneity and lack of clarity. While the available evidence suggests that methylphenidate may be effective in improving chorea symptoms, the findings should be interpreted with caution due to the limitations of the studies reviewed. Nonetheless, more rigorous and comprehensive studies are necessary to provide sufficient evidence for clinical recommendations.

Biallelic variants in ZNF526 cause a severe neurodevelopmental disorder with microcephaly, bilateral cataract, epilepsy and simplified gyration.

BACKGROUND: Next-generation sequencing, combined with international pooling of cases, has impressively enhanced the discovery of genes responsible for Mendelian neurodevelopmental disorders, particularly in individuals affected by clinically undiagnosed diseases. To date, biallelic missense variants in ZNF526 gene, encoding a Krüppel-type zinc-finger protein, have been reported in three families with non-syndromic intellectual disability. METHODS: Here, we describe five individuals from four unrelated families with an undiagnosed neurodevelopmental disorder in which we performed exome sequencing, on a combination of trio-based (4 subjects) or single probands (1 subject). RESULTS: We identified five patients from four unrelated families with homozygous ZNF526 variants by whole exome sequencing. Four had variants resulting in truncation of ZNF526; they were affected by severe prenatal and postnatal microcephaly (ranging from -4 SD to -8 SD), profound psychomotor delay, hypertonic-dystonic movements, epilepsy and simplified gyral pattern on MRI. All of them also displayed bilateral progressive cataracts. A fifth patient had a homozygous missense variant and a slightly less severe disorder, with postnatal microcephaly (-2 SD), progressive bilateral cataracts, severe intellectual disability and unremarkable brain MRI.Mutant znf526 zebrafish larvae had notable malformations of the eye and central nervous system, resembling findings seen in the human holoprosencephaly spectrum. CONCLUSION: Our findings support the role of ZNF526 biallelic variants in a complex neurodevelopmental disorder, primarily affecting brain and eyes, resulting in severe microcephaly, simplified gyral pattern, epileptic encephalopathy and bilateral cataracts.

Highlighting the Dystonic Phenotype Related to GNAO1.

BACKGROUND: Most reported patients carrying GNAO1 mutations showed a severe phenotype characterized by early-onset epileptic encephalopathy and/or chorea. OBJECTIVE: The aim was to characterize the clinical and genetic features of patients with mild GNAO1-related phenotype with prominent movement disorders. METHODS: We included patients diagnosed with GNAO1-related movement disorders of delayed onset (>2 years). Patients experiencing either severe or profound intellectual disability or early-onset epileptic encephalopathy were excluded. RESULTS: Twenty-four patients and 1 asymptomatic subject were included. All patients showed dystonia as prominent movement disorder. Dystonia was focal in 1, segmental in 6, multifocal in 4, and generalized in 13. Six patients showed adolescence or adulthood-onset dystonia. Seven patients presented with parkinsonism and 3 with myoclonus. Dysarthria was observed in 19 patients. Mild and moderate ID were present in 10 and 2 patients, respectively. CONCLUSION: We highlighted a mild GNAO1-related phenotype, including adolescent-onset dystonia, broadening the clinical spectrum of this condition. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Novel KCND3 Variant Underlying Nonprogressive Congenital Ataxia or SCA19/22 Disrupt KV4.3 Protein Expression and K+ Currents with Variable Effects on Channel Properties.

KCND3 encodes the voltage-gated potassium channel KV4.3 that is highly expressed in the cerebellum, where it regulates dendritic excitability and calcium influx. Loss-of-function KV4.3 mutations have been associated with dominant spinocerebellar ataxia (SCA19/22). By targeted NGS sequencing, we identified two novel KCND3 missense variants of the KV4.3 channel: p.S347W identified in a patient with adult-onset pure cerebellar syndrome and p.W359G detected in a child with congenital nonprogressive ataxia. Neuroimaging showed mild cerebellar atrophy in both patients. We performed a two-electrode voltage-clamp recording of KV4.3 currents in Xenopus oocytes: both the p.G345V (previously reported in a SCA19/22 family) and p.S347W mutants exhibited reduced peak currents by 50%, while no K+ current was detectable for the p.W359G mutant. We assessed the effect of the mutations on channel gating by measuring steady-state voltage-dependent activation and inactivation properties: no significant alterations were detected in p.G345V and p.S347W disease-associated variants, compared to controls. KV4.3 expression studies in HEK293T cells showed 53% (p.G345V), 45% (p.S347W) and 75% (p.W359G) reductions in mutant protein levels compared with the wildtype. The present study broadens the spectrum of the known phenotypes and identifies additional variants for KCND3-related disorders, outlining the importance of SCA gene screening in early-onset and congenital ataxia.

Prestatus and status dystonicus in children and adolescents.

AIM: To critically analyse the management of status dystonicus and prestatus dystonicus in children and adolescents, in order to examine clinical features, acute management, and risk of relapse in a paediatric cohort. METHOD: Clinical, demographic, and therapeutic features were analysed according to disease severity. Risk of subsequent relapse was estimated through Kaplan-Meier curves. RESULTS: Thirty-four patients (eight females, 26 males) experiencing 63 episodes of acute dystonia exacerbations at a tertiary referral Italian hospital were identified. Mean age at status dystonicus presentation was 9 years 11 months (11y at inclusion in the study). Onset of dystonia dated back to infancy in most cases. Fourteen patients experienced two or more episodes. Infections were the most common trigger (48%). Benzodiazepines were the most commonly used drugs for acute management. Stereotactic pallidotomy was performed in six cases during status dystonicus, and in two additional patients it was electively performed after medical management. The probability of survival free from status dystonicus relapses was 78% after 4 months and 61% after 27 months. INTERPRETATION: Dystonia exacerbations are potentially life-threating emergencies, with a considerable risk of relapse. Nevertheless, no obvious factors for relapse risk stratification exist. Pallidotomy is a feasible option in medical refractory status dystonicus for patients with limited deep brain stimulation applicability, but the risk of recurrence is elevated. WHAT THIS PAPER ADDS: Acute exacerbations may affect up to 10% of children with dystonia. Infections are the most common precipitant factor. In about 30% of the cases, intensive care unit admission is needed. Subsequent relapses are common, reaching 25% risk at 1 year. Pallidotomy can be considered in medical-refractory cases with no deep brain stimulation applicability.

Clinical and Genetic Overview of Paroxysmal Movement Disorders and Episodic Ataxias.

Paroxysmal movement disorders (PMDs) are rare neurological diseases typically manifesting with intermittent attacks of abnormal involuntary movements. Two main categories of PMDs are recognized based on the phenomenology: Paroxysmal dyskinesias (PxDs) are characterized by transient episodes hyperkinetic movement disorders, while attacks of cerebellar dysfunction are the hallmark of episodic ataxias (EAs). From an etiological point of view, both primary (genetic) and secondary (acquired) causes of PMDs are known. Recognition and diagnosis of PMDs is based on personal and familial medical history, physical examination, detailed reconstruction of ictal phenomenology, neuroimaging, and genetic analysis. Neurophysiological or laboratory tests are reserved for selected cases. Genetic knowledge of PMDs has been largely incremented by the advent of next generation sequencing (NGS) methodologies. The wide number of genes involved in the pathogenesis of PMDs reflects a high complexity of molecular bases of neurotransmission in cerebellar and basal ganglia circuits. In consideration of the broad genetic and phenotypic heterogeneity, a NGS approach by targeted panel for movement disorders, clinical or whole exome sequencing should be preferred, whenever possible, to a single gene approach, in order to increase diagnostic rate. This review is focused on clinical and genetic features of PMDs with the aim to (1) help clinicians to recognize, diagnose and treat patients with PMDs as well as to (2) provide an overview of genes and molecular mechanisms underlying these intriguing neurogenetic disorders.

Biallelic Mutations in TBCD, Encoding the Tubulin Folding Cofactor D, Perturb Microtubule Dynamics and Cause Early-Onset Encephalopathy.

Microtubules are dynamic cytoskeletal elements coordinating and supporting a variety of neuronal processes, including cell division, migration, polarity, intracellular trafficking, and signal transduction. Mutations in genes encoding tubulins and microtubule-associated proteins are known to cause neurodevelopmental and neurodegenerative disorders. Growing evidence suggests that altered microtubule dynamics may also underlie or contribute to neurodevelopmental disorders and neurodegeneration. We report that biallelic mutations in TBCD, encoding one of the five co-chaperones required for assembly and disassembly of the αß-tubulin heterodimer, the structural unit of microtubules, cause a disease with neurodevelopmental and neurodegenerative features characterized by early-onset cortical atrophy, secondary hypomyelination, microcephaly, thin corpus callosum, developmental delay, intellectual disability, seizures, optic atrophy, and spastic quadriplegia. Molecular dynamics simulations predicted long-range and/or local structural perturbations associated with the disease-causing mutations. Biochemical analyses documented variably reduced levels of TBCD, indicating relative instability of mutant proteins, and defective ß-tubulin binding in a subset of the tested mutants. Reduced or defective TBCD function resulted in decreased soluble α/ß-tubulin levels and accelerated microtubule polymerization in fibroblasts from affected subjects, demonstrating an overall shift toward a more rapidly growing and stable microtubule population. These cells displayed an aberrant mitotic spindle with disorganized, tangle-shaped microtubules and reduced aster formation, which however did not alter appreciably the rate of cell proliferation. Our findings establish that defective TBCD function underlies a recognizable encephalopathy and drives accelerated microtubule polymerization and enhanced microtubule stability, underscoring an additional cause of altered microtubule dynamics with impact on neuronal function and survival in the developing brain.

Heterozygous missense variants of SPTBN2 are a frequent cause of congenital cerebellar ataxia.

Heterozygous missense variants in the SPTBN2 gene, encoding the non-erythrocytic beta spectrin 2 subunit (beta-III spectrin), have been identified in autosomal dominant spinocerebellar ataxia type 5 (SCA5), a rare adult-onset neurodegenerative disorder characterized by progressive cerebellar ataxia, whereas homozygous loss of function variants in SPTBN2 have been associated with early onset cerebellar ataxia and global developmental delay (SCAR14). Recently, heterozygous SPTBN2 missense variants have been identified in a few patients with an early-onset ataxic phenotype. We report five patients with non-progressive congenital ataxia and psychomotor delay, 4/5 harboring novel heterozygous missense variants in SPTBN2 and one patient with compound heterozygous SPTBN2 variants. With an overall prevalence of 5% in our cohort of unrelated patients screened by targeted next-generation sequencing (NGS) for congenital or early-onset cerebellar ataxia, this study indicates that both dominant and recessive mutations of SPTBN2 together with CACNA1A and ITPR1, are a frequent cause of early-onset/congenital non-progressive ataxia and that their screening should be implemented in this subgroup of disorders.

Childhood Rapid-Onset Ataxia: Expanding the Phenotypic Spectrum of ATP1A3 Mutations.

ATP1A3 mutations are related to a wide spectrum of clinical conditions, including several defined syndromes as rapid-onset dystonia-parkinsonism (RDP), alternating hemiplegia of childhood (AHC), and cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss (CAPOS), together with many other intermediate phenotypes. Ataxia is always more increasingly reported, either as accessory or prominent sign, in ATP1A3-related conditions, being thus considered as a peculiar feature of this spectrum. Here, we report three cases of childhood rapid-onset ataxia due to two different ATP1A3 variants. Interestingly, two patients (mother and son) showed a variant c.2266C>T (p.R756C), while the third carried the c.2452G>A (p.E818K) variant, commonly described in association with CAPOS syndrome. Our report contributes to extent the phenotypic spectrum of ATP1A3 mutations, remarking childhood rapid-onset ataxia as an additional clinical presentation of ATP1A3-related conditions. Finally, we discussed this phenomenology in the light of translational evidence from a RDP animal model.

Features of aura in paediatric migraine diagnosed using the ICHD 3 beta criteria.

Background In children and adolescents, the prevalence rate of migraine with aura is 1.6%. Few studies concerning migraine with aura features in paediatric population have been reported. Aim The aim of our study was to investigate clinical features of aura in a retrospective cohort of children with migraine with aura. Furthermore, we studied whether the International Classification of Headache Disorder (ICHD) 3 beta version criteria could efficiently detect migraine with aura in a paediatric population. Results We included 164 patients who experienced aura associated with headache (mean age 9.92 ± 2.64 years). When the ICHD-II criteria were used, a final diagnosis of migraine with typical aura was obtained in 15.3% of patients, probable migraine with typical aura in 13.4%, and typical aura with headache in 61.8%, while in in 9.5% of patients the diagnosis was undetermined. According to ICHD-3 beta, we diagnosed migraine with typical aura in 77.7% of patients, probable migraine with typical aura in 13.4%, and an undetermined diagnosis in 9.5% (less than two attacks). Conclusion Aura features did not depend on age and were similar to those of adults. However, the headache could be difficult to classify if headache duration was considered. In this view, the ICHD-3 beta offers the advantage of not considering headache features, including pain duration, for the diagnosis of migraine with typical aura, thus making this diagnosis easier in children and adolescents.

Diagnosis of primary headache in children younger than 6 years: A clinical challenge.

Background Criteria defined by the International headache Society are commonly used for the diagnosis of the different headache types in both adults and children. However, some authors have stressed some limits of these criteria when applied to preschool age. Objective Our study aimed to describe the characteristics of primary headaches in children younger than 6 years and investigate how often the International Classification of Headache Disorders (ICHD) criteria allow a definitive diagnosis. Methods This retrospective study analysed the clinical feature of 368 children younger than 6 years with primary headache. Results We found that in our patients the percentage of undefined diagnosis was high when either the ICHD-II or the ICHD-III criteria were used. More than 70% of our children showed a duration of their attacks shorter than 1 hour. The absence of photophobia/phonophobia and nausea/vomiting significantly correlate with tension-type headache (TTH) and probable TTH. The number of first-degree relatives with migraine was positively correlated to the diagnosis of migraine in the patients ( p < 0.001). Conclusions Our study showed that the ICHD-III criteria are difficult to use in children younger than 6 years. The problem is not solved by the reduction of the lowest duration limit for the diagnosis of migraine to 1 hour, as was done in the ICHD-II.

Role of the Attachment Style in Determining the Association Between Headache Features and Psychological Symptoms in Migraine Children and Adolescents. An Analytical Observational Case-Control Study.

OBJECTIVE: We aimed to study the role of attachment style on headache severity and psychological symptoms in migraineurs children/adolescents. Moreover, we investigated the association between attachment style, migraine severity, and psychological symptoms. BACKGROUND: Attachment theory suggests that early interpersonal relationships may be important determinants of psychopathology and pain management. In particular, individuals with insecure attachment styles have been shown to experience more pain than people with secure attachment style. Few studies focused on headache and data on attachment style in pediatric headache are scarce. METHODS: We studied 90 migraineurs (mean age 12.2 ± 2.6 years; female: 54, male: 36). Patients were divided in two groups according to headache attack frequency: (1) high frequency (HF) patients, having from weekly to daily episodes and (2) low frequency (LF) patients, showing ≤3 episodes per month. According to headache attack intensity, patients were classified in two groups: (1) mild pain (MP), allowing the patient to continue his/her daily activities and (2) severe pain (SP), leading to interruption of patient activities or forcing the child to go to bed. The psychological screening was assessed by SAFA Anxiety, Depression, and Somatization questionnaires. Attachment style was measured by the semi-projective test Separation Anxiety Test. Patients were divided into "secure," "avoidant," "ambivalent," and "disorganized/confused" attachment patterns. RESULTS: We found a significant relationship between the attachment style and migraine features. The ambivalent attachment was the most common style among patients reporting high attack frequency (51%) and severe pain intensity (50%). Anxiety (SAFA-A Tot: F = 23.3, P < .001), depression (SAFA-D Tot: F = 11.8, P < .001), and somatization (SAFA-S Tot: F = 10.1, P < .001) were higher in patients with ambivalent attachment style. Moreover, our results showed an association between high attack frequency and high anxiety levels, in children with ambivalent attachment style (F = 6.7, P < .002). CONCLUSIONS: Ambivalent attachment style may be a common vulnerability factor that impacts on pain severity, anxiety, depression, and somatization symptoms in young migraineurs. In particular, the present study provides the first evidence of the role of insecure attachment on the relationship between pain severity and psychological symptoms in migraine children.

Headache as an emergency in children and adolescents.

Pediatric and adolescence headache is one of the most common causes of access in emergency departments (ED). Primary headache and headache secondary to self-limited conditions are the majority of cases. Secondary life-threatening headaches are less frequent and may be recognized by a careful history and physical examination. The primary objective for ED physicians is to recognize the serious life-threatening conditions requiring immediate medical care among the wide spectrum of headache diagnoses.

Migraine equivalents and related symptoms, psychological profile and headache features: which relationship?

BACKGROUND: Migraine equivalents are common clinical conditions in children suffering from headache. Very few studies dealt with the psychological profile of children/adolescents with migraine equivalents. Our main aim was to compare the psychological profile between migraine children with and without migraine equivalents. Moreover, as secondary aim, exclusively in children with migraine equivalents, we investigated the possible relationship between migraine attack frequency and intensity and psychological factors. METHODS: We enrolled 136 young migraineurs. They were divided in two groups (patients with and without migraine equivalents). The psychological profile was assessed by means of SAFA Anxiety and Somatization questionnaires. RESULTS: Migraine equivalents were present in 101 patients (74.3%). Anxiety (p = 0.024) and somatization (p = 0.001) levels, but not hypochondria (p = 0.26), were higher in patients with migraine equivalents. In children with migraine equivalents, a low frequency of attacks was related to separation anxiety (p = 0.034). CONCLUSIONS: Migraine equivalents patients tend to feel more fearful and to experience more shyness. This, together with the tendency to somatization, may lead them to become vigilant in attachment relationships with their caregivers.

Dyskinesia as a new adverse effect of hormonal treatment in West syndrome.

West syndrome is an age-dependent epileptic encephalopathy. Despite potential side effects, hormonal therapy remains the main treatment for West syndrome. Here, we report on 10 patients receiving steroid treatment who presented with unusual, mostly hyperkinetic, movements. Facial grimacing, repetitive mouth opening, adduction and abduction of upper and lower extremities, and periodical strabismus in different combinations were observed in all patients, independent of formulation, dose, duration, and efficacy of treatment. Symptoms disappeared in sleep and reappeared immediately on arousal. Dyskinesias stopped gradually after a month of discontinuation of treatment. Repeated EEGs did not show corresponding epileptiform activity. We conclude that these abnormal movements can be attributed to side effects of hormonal treatment.

Movement disorder phenotype in CTNNB1-syndrome: A complex but recognizable phenomenology.

INTRODUCTION: CTNNB1 gene loss-of-function variants cause Neurodevelopmental disorder with spastic diplegia and visual defects (NEDSDV, OMIM 615075). Although motor impairment represents a core feature of this condition, the motor phenotype remains poorly described. We systematically assessed a cohort of 14 patients with disease-causing CTNNB1 variants to better characterize the movement disorder phenotype. METHODS: patients were enrolled at Bambino Gesù Children's Hospital in Rome, Italy, between January 2019 and February 2024. 14 participants were included and underwent extensive genetic and neurologic examination. Clinical features, neuroimaging and neurophysiological investigations were retrospectively analyzed from medical charts and video recordings. RESULTS: 13 out of 14 patients showed motor disorders (one only showing mild coordination difficulties). 12 presented abnormal gait (11 patients with broad-based gait, one with narrow-based in-toeing gait, one with broad-based gait with unilateral intoeing). One did not achieve walking ability. 13 patients presented progressive lower limbs hypertonia without overt pyramidal signs. Five patients reported exaggerated startle, three developed upper body (prominently cervical) dystonia in the second decade, with or without bradykinesia (2/13). Treatment efficacy was variable: botulinum toxin was (at least partially) effective in 5/6, levodopa in 1 of 4 treated patients. CONCLUSIONS: CTNNB1-syndrome is associated with a peculiar, but recognizable movement disorder phenotype, encompassing complex gait disorders with progressive lower limb hypertonia, exaggerated startle, and possible occurrence in the second decade of life of upper body dystonia with or without bradykinesia.

Clinical features, anger management and anxiety: a possible correlation in migraine children.

BACKGROUND: Psychological factors can increase severity and intensity of headaches. While great attention has been placed on the presence of anxiety and/or depression as a correlate to a high frequency of migraine attacks, very few studies have analyzed the management of frustration in children with headache. Aim of this study was to analyze the possible correlation between pediatric migraine severity (frequency and intensity of attacks) and the psychological profile, with particular attention to the anger management style. METHODS: We studied 62 migraineurs (mean age 11.2 ± 2.1 years; 29 M and 33 F). Patients were divided into four groups according to the attack frequency (low, intermediate, high frequency, and chronic migraine). Pain intensity was rated on a 3-levels graduate scale (mild, moderate and severe pain). Psychological profile was assessed by Picture Frustration Study test for anger management and SAFA-A scale for anxiety. RESULTS: We found a relationship between IA/OD index (tendency to inhibit anger expression) and both attack frequency (r = 0.328, p = 0.041) and intensity (r = 0.413, p = 0.010). When we analyzed the relationship between anxiety and the headache features, a negative and significant correlation emerged between separation anxiety (SAFA-A Se) and the frequency of attacks (r = -0.409, p = 0.006). In our patients, the tendency to express and emphasize the presence of the frustrating obstacle (EA/OD index) showed a positive correlation with anxiety level ("Total anxiety" scale: r = 0.345; p = 0.033). CONCLUSIONS: Our results suggest that children suffering from severe migraine tend to inhibit their angry feelings. On the contrary, children with low migraine attack frequency express their anger and suffer from separation anxiety.