OBJECTIVE: To analyze the clinical characteristics and genotypic changes of six children with RARS2 gene variants. METHODS: The clinical data of 6 children with RARS2 gene variants diagnosed at the Third Affiliated Hospital of Zhengzhou University from January 2017 to August 2024 were collected. Genetic variants were detected using trio-whole exome sequencing. Genomic DNA was extracted from samples and subjected to high-throughput sequencing. Variants were detected and analyzed using relevant databases and software. Pathogenic variants were validated by Sanger sequencing. The protein structure encoded by a previously unreported variant was predicted using a SWISS-MODEL online server. This study was approved by the Medical Ethics Committee of the Third Affiliated Hospital of Zhengzhou University (Ethics No.: 2024-373-01). RESULTS: Among the six children, four were males and two were females, with the most recent follow-up age ranging from 1-year-and-1-month to 7 years old. The age of onset was under 1 year in all cases. All six children exhibited seizures, including infantile spasms in three, spasms and tonic spasms in one, and focal seizures in two. One child became seizure-free for 4 ~ 5 years following Valproic acid combined with topiramate and adrenocorticotropic hormone (ACTH) pulse therapy, but subsequently experienced a relapse. Another child has remained seizure-free for nearly one year with oral sodium valproate, levetiracetam, and a "cocktail" therapy. Seizures were not controlled in the remaining four children. Pontocerebellar hypoplasia was observed on neuroimaging in two children. All six patients exhibited severe psychomotor retardation. A total of 10 RARS2 gene variants were identified, three of which were previously unreported. CONCLUSION The predominant clinical features of Pontocerebellar hypoplasia associated with RARS2 gene variants include infantile onset, severe psychomotor retardation or regression, drug-resistant epilepsy, and feeding difficulties. The characteristic neuroimaging finding is pontocerebellar hypoplasia. However, its appearance may vary widely with time. The majority of affected children have a poor prognosis.
Humans ; Male ; Female ; Child, Preschool ; Infant ; Child ; Olivopontocerebellar Atrophies/genetics* ; Arginine-tRNA Ligase/genetics* ; Mutation ; Cerebellar Diseases

BACKGROUND: Reports evaluating the efficacy of transcranial sonography (TCS) for the differential diagnosis of Parkinson disease (PD) and other movement disorders in China are scarce. Therefore, this study aimed to assess the application of TCS for the differential diagnosis of PD, multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and essential tremor (ET) in Chinese individuals. METHODS: From 2017 to 2019, 500 inpatients treated at the Department of Dyskinesia, Beijing Tiantan Hospital, Capital Medical University underwent routine transcranial ultrasound examination. The cross-sections at the midbrain and thalamus levels were scanned, and the incidence rates of substantia nigra (SN) positivity and the incidence rates of lenticular hyperechoic area were recorded. The echo of the SN was manually measured. RESULTS: Of the 500 patients, 125 were excluded due to poor signal in temporal window sound transmission. Among the 375 individuals with good temporal window sound transmission, 200 were diagnosed with PD, 90 with ET, 50 with MSA, and 35 with PSP. The incidence rates of SN positivity differed significantly among the four patient groups (χ2 = 121.061, P < 0.001). Between-group comparisons were performed, and the PD group showed a higher SN positivity rate than the ET (χ2 = 94.898, P < 0.017), MSA (χ2 = 57.619, P < 0.017), and PSP (χ2 = 37.687, P < 0.017) groups. SN positivity showed a good diagnostic value for differentiating PD from the other three movement diseases, collectively or individually. The incidences of lenticular hyperechoic area significantly differed among the four patient groups (χ2 = 38.904, P < 0.001). Next, between-group comparisons were performed. The lenticular hyperechoic area was higher in the PD group than in the ET (χ2 = 6.714, P < 0.017) and MSA (χ2 = 18.680, P < 0.017) groups but lower than that in the PSP group (χ2 = 0.679, P > 0.017). CONCLUSION SN positivity could effectively differentiate PD from ET, PSP, and MSA in a Chinese population.
Diagnosis, Differential ; Humans ; Multiple System Atrophy/diagnostic imaging* ; Parkinson Disease/diagnostic imaging* ; Substantia Nigra/diagnostic imaging* ; Supranuclear Palsy, Progressive

OBJECTIVE: To explore the genetic basis for a fetus with cerebellar dysplasia and widened lateral ventricles. METHODS: The couple have elected induced abortion after careful counseling. Skin tissue sample from the abortus and peripheral venous blood samples from both parents were collected for the extraction of genomic DNA, which was then subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: Prenatal ultrasonography showed increased nuchal translucency (0.4 cm) and widened lateral ventricles. Magnetic resonance imaging revealed infratentorial brain dysplasia. By DNA sequencing, the fetus was found to carry compound heterozygous variants c.1A>G and c.1564G>A of the RARS2 gene, which were inherited from its father and mother, respectively. Among these, c.1A>G was known to be pathogenic, but the pathogenicity of c.1564G>A was unreported previously. Based on the American College of Medical Genetics and Genomics guidelines, the c.1564G>A variant of RARS2 gene was predicted to be likely pathogenic(PM2+PM3+PP3+PP4). CONCLUSION The compound heterozygous variants c.1A>G and c.1564G>A of RARS2 gene contributed to the fetus suffering from pontocerebellar hypoplasia type 6, which expanded variant spectrum of RARS2 gene.
Female ; Fetus ; Genomics ; Humans ; Mutation ; Olivopontocerebellar Atrophies ; Pregnancy ; Whole Exome Sequencing

BACKGROUND: Sleep disorders are common but under-researched symptoms in patients with multiple system atrophy (MSA). We investigated the frequency and factors associated with sleep-related symptoms in patients with MSA and the impact of sleep disturbances on disease severity. METHODS: This cross-sectional study involved 165 patients with MSA. Three sleep-related symptoms, namely Parkinson's disease (PD)-related sleep problems (PD-SP), excessive daytime sleepiness (EDS), and rapid eye movement sleep behavior disorder (RBD), were evaluated using the PD Sleep Scale-2 (PDSS-2), Epworth Sleepiness Scale (ESS), and RBD Screening Questionnaire (RBDSQ), respectively. Disease severity was evaluated using the Unified MSA Rating Scale (UMSARS). RESULTS: The frequency of PD-SP (PDSS-2 score of ≥18), EDS (ESS score of ≥10), and RBD (RBDSQ score of ≥5) in patients with MSA was 18.8%, 27.3%, and 49.7%, respectively. The frequency of coexistence of all three sleep-related symptoms was 7.3%. Compared with the cerebellar subtype of MSA (MSA-C), the parkinsonism subtype of MSA (MSA-P) was associated with a higher frequency of PD-SP and EDS, but not of RBD. Binary logistic regression revealed that the MSA-P subtype, a higher total UMSARS score, and anxiety were associated with PD-SP; that male sex, a higher total UMSARS score, the MSA-P subtype, and fatigue were associated with EDS; and that male sex, a higher total UMSARS score, and autonomic onset were associated with RBD in patients with MSA. Stepwise linear regression showed that the number of sleep-related symptoms (PD-SP, EDS, and RBD), disease duration, depression, fatigue, and total Montreal Cognitive Assessment score were predictors of disease severity in patients with MSA. CONCLUSIONS Sleep-related disorders were associated with both MSA subtypes and the severity of disease in patients with MSA, indicating that sleep disorders may reflect the distribution and degree of dopaminergic/non-dopaminergic neuron degeneration in MSA.
Cross-Sectional Studies ; Humans ; Male ; Multiple System Atrophy ; REM Sleep Behavior Disorder ; Severity of Illness Index ; Sleep

The aim of this study was to compare and quantify the spatiotemporal and gait parameters obtained by foot pressure analysis during the gait in a group of Parkinson's disease (PD) patients compared with other Parkinsonism diseases, especially multiple system atrophy (MSA). Thirty-seven out of ninety-three patients who visited the center of neurology or rehabilitation with features of Parkinsonism were recruited. Spatiotemporal gait parameters were collected using gait analysis system. The results did not differ in terms of the stride length, step width, double stance phase, stride time, cadence, velocity, gait line and single support line differences, anterior-posterior position of center of pressure, and maximal gait line velocity; the lateral symmetry showed a significant difference between the PD and the MSA groups (p < 0.05). The study evaluated the differences in terms of spatiotemporal parameters between the PD and MSA along with other Parkinsonism diseases; it showed that the PD patients had a gait tendency to deviate laterally compared to the MSA patients. The result suggests conducting the gait foot pressure analysis might help distinguish PD from other Parkinsonism diseases in early stage, aiding the early decision for the treatment plans.
Foot ; Gait ; Humans ; Multiple System Atrophy ; Neurology ; Parkinson Disease ; Parkinsonian Disorders ; Rehabilitation

BACKGROUND AND PURPOSE: It is essential to develop a reliable predictive serum biomarker for Parkinson's disease (PD). The accumulation of alpha-synuclein (αSyn) and up-regulated expression of Rab35 participate in the etiology of PD. The purpose of this investigation was to determine whether the combined assessment of serum αSyn and Rab35 is a useful predictive biomarker for PD. METHODS: Serum levels of αSyn or Rab35 were determined in serum samples from 59 sporadic PD patients, 19 progressive supranuclear palsy (PSP) patients, 20 multiple system atrophy (MSA) patients, and 60 normal controls (NC). Receiver operating characteristics (ROC) curves were calculated to determine the diagnostic accuracy of αSyn or/and Rab35 in discriminating PD patients from NC or atypical parkinsonian patients. RESULTS: The levels of αSyn and Rab35 were increased in PD patients. The serum level of Rab35 was positively correlated with that of αSyn in PD patients. Compared to analyzing αSyn or Rab35 alone, the combined analysis of αSyn and Rab35 produced a larger area under the ROC curve and performed better in discriminating PD patients from NC, MSA patients, or PSP patients. When age was dichotomized at 55, 60, 65, or 70 years, the combined assessment of αSyn and Rab35 for classifying PD was better in the group below the cutoff age than in the group above the cutoff age. CONCLUSIONS: Combined assessment of serum αSyn and Rab35 is a better biomarker for discriminating PD patients from NC or atypical parkinsonian patients, and is a useful predictive biomarker for younger sporadic PD patients.
alpha-Synuclein ; Humans ; Multiple System Atrophy ; Parkinson Disease ; ROC Curve ; Supranuclear Palsy, Progressive

OBJECTIVE: To clarify the specificity of the ‘hot cross bun’ sign (HCBS) for multiple system atrophy (MSA) in adult cerebellar ataxia or parkinsonism. METHODS: The radiologic information systems at an academic center and affiliated veterans' hospital were queried using the keywords ‘hot cross bun,’ ‘pontocerebellar,’ ‘cruciate,’ ‘cruciform,’ ‘MSA,’ ‘multiple system atrophy,’ and ‘multisystem atrophy.’ Scans were reviewed by a neurologist and neuroradiologist to identify the HCBS. Subjects with the HCBS were reviewed by 2 neurologists to identify the most likely etiology of the patient's neurologic symptoms. RESULTS: Eleven cases were identified. Etiologies included MSA (4 probable, 2 possible), hereditary cerebellar ataxia (3/11), probable dementia with Lewy bodies (1/11), and uncertain despite autopsy (1/11). CONCLUSION: MSA was the most common etiology. However, 5 of the 11 patients did not have MSA. The most common alternate etiology was an undefined hereditary cerebellar ataxia (3/11).
Adult ; Autopsy ; Cerebellar Ataxia ; Dementia ; Hexachlorobenzene ; Humans ; Lewy Bodies ; Magnetic Resonance Imaging ; Multiple System Atrophy ; Neurologic Manifestations ; Olivopontocerebellar Atrophies ; Parkinsonian Disorders ; Radiology Information Systems ; Sensitivity and Specificity

OBJECTIVE: Multiple System Atrophy (MSA) and progressive supranuclear palsy (PSP) are rapidly progressive forms of degenerative Parkinsonism. The difficulties of diagnosing MSA and PSP in their early stages may lead to delayed referral to appropriate specialists and distress to patients, as well as delaying symptomatic treatment and participation in clinical trials. This work aimed to describe the symptoms that patients with MSA and PSP developed and plot their emergence relative to final diagnosis using a median onset in months. METHODS: Forty-seven patients from the United Kingdom with MSA or PSP diagnosed by a movement disorder specialist were interviewed with carers or relatives to establish milestone onset. This was corroborated using clinical notes and letters. RESULTS: In the MSA cohort (n = 23), autonomic symptoms (median 5.5 months before diagnosis) and falls (median 1 month before diagnosis) were the two clinical milestones which occurred before diagnosis. In the PSP cohort (n = 24), falling was the only milestone which occurred before diagnosis (median of 18.5 months). CONCLUSION: This study shows that PSP patients experience falling more than a year and a half an average before receiving a diagnosis and although MSA patients also tended to fall, this was much closer to the time of diagnosis. Further work with larger cohorts may illustrate whether these preliminary findings can be generalised to guide diagnosis and management.
Accidental Falls ; Advance Care Planning ; Caregivers ; Cohort Studies ; Delayed Diagnosis ; Diagnosis ; Great Britain ; Humans ; Movement Disorders ; Multiple System Atrophy ; Parkinsonian Disorders ; Referral and Consultation ; Retrospective Studies ; Specialization ; Supranuclear Palsy, Progressive

The aggregation of α-synuclein (α-syn) has been implicated in the pathogenesis of many neurodegenerative disorders, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Postmortem analyses of α-syn pathology, especially that of PD, have suggested that aggregates progressively spread from a few discrete locations to wider brain regions. The neuron-to-neuron propagation of α-syn has been suggested to be the underlying mechanism by which aggregates spread throughout the brain. Many cellular and animal models has been created to study cell-to-cell propagation. Recently, it has been shown that a single injection of preformed fibrils (PFFs) made of recombinant α-syn proteins into various tissues and organs of many different animal species results in widespread α-syn pathology in the central nervous system (CNS). These PFF models have been extensively used to study the mechanism by which aggregates spread throughout the brain. Here, we review what we have learned from PFF models, describe the nature of PFFs and the neuropathological features, neurophysiological characteristics, and behavioral outcomes of the models.
alpha-Synuclein ; Animals ; Brain ; Central Nervous System ; Dementia ; Lewy Bodies ; Models, Animal ; Multiple System Atrophy ; Neurodegenerative Diseases ; Parkinson Disease ; Pathology

In recent years, several radiotracers that selectively bind to pathological tau proteins have been developed. Evidence is emerging that binding patterns of in vivo tau positron emission tomography (PET) studies in Alzheimer's disease (AD) patients closely resemble the distribution patterns of known neurofibrillary tangle pathology, with the extent of tracer binding reflecting the clinical and pathological progression of AD. In Lewy body diseases (LBD), tau PET imaging has clearly revealed cortical tau burden with a distribution pattern distinct from AD and increased cortical binding within the LBD spectrum. In progressive supranuclear palsy, the globus pallidus and midbrain have shown increased binding most prominently. Tau PET patterns in patients with corticobasal syndrome are characterized by asymmetrical uptake in the motor cortex and underlying white matter, as well as in the basal ganglia. Even in the patients with multiple system atrophy, which is basically a synucleinopathy, ¹⁸F-flortaucipir, a widely used tau PET tracer, also binds to the atrophic posterior putamen, possibly due to off-target binding. These distinct patterns of tau-selective radiotracer binding in the various degenerative parkinsonisms suggest its utility as a potential imaging biomarker for the differential diagnosis of parkinsonisms.
Alzheimer Disease ; Basal Ganglia ; Diagnosis, Differential ; Electrons ; Globus Pallidus ; Humans ; Lewy Bodies ; Mesencephalon ; Motor Cortex ; Multiple System Atrophy ; Neurofibrillary Tangles ; Parkinsonian Disorders ; Pathology ; Positron-Emission Tomography ; Putamen ; Supranuclear Palsy, Progressive ; tau Proteins ; White Matter