Tremor in Spinocerebellar Ataxia: A Scoping Review.

Background: Spinocerebellar ataxia (SCA) denotes an expanding list of autosomal dominant cerebellar ataxias. Although tremor is an important aspect of the clinical spectrum of the SCAs, its prevalence, phenomenology, and pathophysiology are unknown. Objectives: This review aims to describe the various types of tremors seen in the different SCAs, with a discussion on the pathophysiology of the tremors, and the possible treatment modalities. Methods: The authors conducted a literature search on PubMed using search terms including tremor and the various SCAs. Relevant articles were included in the review after excluding duplicate publications. Results: While action (postural and intention) tremors are most frequently associated with SCA, rest and other rare tremors have also been documented. The prevalence and types of tremors vary among the different SCAs. SCA12, common in certain ethnic populations, presents a unique situation, where the tremor is typically the principal manifestation. Clinical manifestations of SCAs may be confused with essential tremor or Parkinson's disease. The pathophysiology of tremors in SCAs predominantly involves the cerebellum and its networks, especially the cerebello-thalamo-cortical circuit. Additionally, connections with the basal ganglia, and striatal dopaminergic dysfunction may have a role. Medical management of tremor is usually guided by the phenomenology and associated clinical features. Deep brain stimulation surgery may be helpful in treatment-resistant tremors. Conclusions: Tremor is an elemental component of SCAs, with diverse phenomenology, and emphasizes the role of the cerebellum in tremor. Further studies will be useful to delineate the clinical, pathophysiological, and therapeutic aspects of tremor in SCAs.

Recurrent CNTN1 antibody-positive nodopathy: a case report and literature review.

Background: Contactin-1 (CNTN1) antibody-positive nodopathy is rare and exhibits distinct clinical symptoms such as tremors and ataxia. However, the mechanisms of these symptoms and the characteristics of the cerebral spinal fluid (CSF) remain unknown. Case presentation: Here, we report a case of recurrent CNTN1 antibody-positive nodopathy. Initially, a 45-year-old woman experiencing numbness in the upper limbs and weakness in the lower limbs was diagnosed with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Eleven years later, her symptoms worsened, and she began to experience tremors and ataxia. Tests for serum CNTN1, GT1a, and GQ1b antibodies returned positive. Subsequently, she was diagnosed with CNTN1 antibody-positive nodopathy and underwent plasmapheresis therapy, although the treatment's efficacy was limited. To gain a deeper understanding of the disease, we conducted a comprehensive literature review, identifying 52 cases of CNTN1 antibody-positive nodopathy to date, with a tremor prevalence of 26.9%. Additionally, we found that the average CSF protein level in CNTN1 antibody-positive nodopathy was 2.57 g/L, with 87% of patients exhibiting a CSF protein level above 1.5 g/L. Conclusion: We present a rare case of recurrent CNTN1 antibody-positive nodopathy. Our findings indicate a high prevalence of tremor (26.9%) and elevated CSF protein levels among patients with CNTN1 antibody-positive nodopathy.

A comparison of quantitative parameters of axial posture and spinal mobility between motor subtypes of Parkinson's disease.

Background and purpose:

Parkinson’s disease (PD) is a heterogeneous neurodegenerative disorder characterized by contradictory clinical outcomes among its several subtypes. The disease can manifest with a tremor-dominant (TD) or a non-tremor-dominant (NTD) phenotype. Although the TD subtype may show a better prognosis, there is limited information on the phenotypic differences regarding the level of axial symptoms. For this reason, in this study it was aimed to make a quantitative comparison of axial posture and spinal mobility between PD with TD and NTD. 

This case-control study was conducted on 94 patients with diagnosed PD. A group diagnosis approach was used in the study, such that the diagnosis of each patient was confirmed, and they were assig-ned to TD and NTD groups by a neurologist expert on movement disorders. Of the patients with PD, 61 were in the TD group, and 33 were in the NTD group. Spinal mouse was used to measure spinal posture and spinal mobility in both sagittal and frontal planes. 

Two groups of 61 patients (25 male + 36 female) with TD-PD (mean age: 64.49±10.37 years) and 33 patients (20 male +13 female) with NTD-PD (mean age: 63.45±9.11 years) were enrolled in the study. There were no significant differences bet­ween the patients with TD and NTD in terms of sagittal and frontal postures (p>0.05). In addition to this, anterior trunk tilt was found to significantly increase as the disease stage advanced in both groups. While the greatest anterior trunk tilt change in the TD-PD group was observed in the 3rd stage, NTD-PD group was in the 2.5th stage. Aside from this, the out­comes of the spinal mobility measurements in the frontal and sagittal planes were similar between the groups (p>0.05).

It is widely acknowledged that many clinical aspects of the TD and NTD forms of PD differ; however, in our study, it was observed that there may be no difference in the axial symptoms of the patients with PD in terms of classification according to tremor dominance.

Isolated Toe Tremor Associated with Antiphospholipid Syndrome.

The antiphospholipid syndrome (APS) is defined by the presence of antiphospholipid antibodies and related disorders, generally thromboses, miscarriages, livedo reticularis or heart valve abnormalities. It is thought to have a prevalence of about 40-50 cases per 100,000 in the general population.1 Several neurological disorders have been associated with APS, most commonly stroke, but non-stroke complications, thought due to auto- immune problems, have been noted, with chorea being the most common. Isolated toe tremor, that is, without any other neurological signs or symptoms, has not been reported. We describe a case of recurrent isolated uni- lateral toe tremor in an otherwise healthy woman with long-standing APS.

Reversible encephalitis-like episodes in fragile X-associated tremor/ataxia syndrome: a case report.

BACKGROUND: Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by CGG repeat expansion of FMR1 gene. Both FXTAS and neuronal intranuclear inclusion disease (NIID) belong to polyglycine diseases and present similar clinical, radiological, and pathological features, making it difficult to distinguish these diseases. Reversible encephalitis-like attacks are often observed in NIID. It is unclear whether they are presented in FXTAS and can be used for differential diagnosis of NIID and FXTAS. CASE PRESENTATION: A 63-year-old Chinese male with late-onset gait disturbance, cognitive decline, and reversible attacks of fever, consciousness impairment, dizziness, vomiting, and urinary incontinence underwent neurological assessment and examinations, including laboratory tests, electroencephalogram test, imaging, skin biopsy, and genetic test. Brain MRI showed T2 hyperintensities in middle cerebellar peduncle and cerebrum, in addition to cerebellar atrophy and DWI hyperintensities along the corticomedullary junction. Lesions in the brainstem were observed. Skin biopsy showed p62-positive intranuclear inclusions. The possibilities of hypoglycemia, lactic acidosis, epileptic seizures, and cerebrovascular attacks were excluded. Genetic analysis revealed CGG repeat expansion in FMR1 gene, and the number of repeats was 111. The patient was finally diagnosed as FXTAS. He received supportive treatment as well as symptomatic treatment during hospitalization. His encephalitic symptoms were completely relieved within one week. CONCLUSIONS: This is a detailed report of a case of FXTAS with reversible encephalitis-like episodes. This report provides new information for the possible and rare features of FXTAS, highlighting that encephalitis-like episodes are common in polyglycine diseases and unable to be used for differential diagnosis.

Movement Disorders in Patients with Subacute Sclerosing Panencephalitis: A Systematic Review.

BACKGROUND: Subacute sclerosing panencephalitis (SSPE) is a complication of measles, occurring after a latency of 4-10 years. It continues to occur in developing countries although resurgence is being reported from developed countries. Characteristic features include progressive neuropsychiatric issues, myoclonus, seizures, movement disorders and visual impairment. Electroencephalography (EEG) typically shows periodic generalized discharges, and elevated CSF anti-measles antibodies are diagnostic. Movement disorders are being increasingly recognized as part of the clinical spectrum, and range from hyperkinetic (chorea, dystonia, tremor, tics) to hypokinetic (parkinsonism) disorders and ataxia. OBJECTIVES: This article aims to comprehensively review the spectrum of movement disorders associated with SSPE. METHODS: A literature search was conducted in PubMed and EMBASE databases in December 2023 and articles were identified for review. RESULTS: Movement disorders reported in SSPE included hyperkinetic (chorea, dystonia, tremor and tics), hypokinetic (parkinsonism), ataxia and extraocular movement disorders. Myoclonus, a core clinical feature, was the most frequent "abnormal movement." Movement disorders were observed in all clinical stages, and could also be a presenting feature, even sans myoclonus. Hyperkinetic movement disorders were more common than hypokinetic movement disorders. An evolution of movement disorders was observed, with ataxia, chorea and dystonia occurring earlier, and parkinsonism later in the disease. Neuroradiological correlates of movement disorders remained unclear. CONCLUSION: A wide spectrum of movement disorders was observed throughout the clinical stages of SSPE. Most data were derived from case reports and small case series. Multicentric longitudinal studies are required to better delineate the spectrum and evolution of movement disorders in SSPE.

Motor and non-motor outcome in tremor dominant Parkinson's disease after MR-guided focused ultrasound thalamotomy.

BACKGROUND AND OBJECTIVES: Magnetic Resonance-guided Focused Ultrasound (MRgFUS) is an emerging technique for the treatment of severe, medication-refractory tremor syndromes. We here report motor and non-motor outcomes 6 and 12 months after unilateral MRgFUS thalamotomy in tremor-dominant Parkinson's disease (tdPD). METHODS: 25 patients with tdPD underwent neuropsychological evaluation including standardized questionnaires of disability, quality of life (QoL), mood, anxiety, apathy, sleep disturbances, and cognition at baseline, 6 and 12 months after MRgFUS. Motor outcome was evaluated using the Clinical Rating Scale for Tremor (CRST) and Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS). In addition, side effects and QoL of family caregivers were assessed. RESULTS: 12 months after MRgFUS significant improvements were evident in the tremor subscores. Patients with concomitant rest and postural tremor showed better tremor outcomes compared to patients with predominant rest tremor. There were no differences in the non-motor assessments. No cognitive decline was observed. Side effects were mostly transient (54%) and classified as mild (62%). No changes in the caregivers' QoL could be observed. CONCLUSION: We found no changes in mood, anxiety, apathy, sleep, cognition or persistent worsening of gait disturbances after unilateral MRgFUS thalamotomy in tdPD. Concomitant postural tremors responded better to treatment than predominant rest tremors.

[Tremor-dominant form of Parkinson's disease]. / Tremor-dominantnaya forma bolezni Parkinsona.

The article is of a review nature and is devoted to tremor, one of the maladaptive and difficult-to-treat symptoms of Parkinson's disease (PD). Along with the classic rest tremor, patients with PD may experience tremor of other modalities: postural tremor, kinetic tremor, which reflects a multimodal mechanism of tremor formation involving multiple neurotransmitter systems. The unpredictable response to therapeutic options, the ambiguous response to levodopa, also reflects the role of multiple underlying pathophysiological processes. Among the drug methods of tremor correction, preference is given to dopamine receptor agonists - due to the spectrum of their pharmaceutical action, high efficiency in relation to all leading motor and a number of non-motor manifestations. The evidence for advanced neurosurgical, non-invasive modalities is mixed, and there are insufficient comparative studies to assess their efficacy in patients with tremor-dominant forms of PD.

Cerebrotendinous xanthomatosis with tremor as the main manifestation: A case report.

INTRODUCTION: Cerebrotendinous xanthomatosis (CTX) is an autosomal recessive lipid metabolism disorder. It is caused by a defect in the sterol-27-hydroxylase gene, leading to the deposition of cholesteryl and bile alcohol in large amounts, causing a variety of clinical manifestations; however, tremor as the main manifestation of CTX has not been reported. PATIENTS CONCERNS AND CLINICAL FINDINGS: Herein, we report a 27-year-old woman, who developed head and body tremors at the age of 12 years. Many hospitals misdiagnosed her condition as idiopathic tremor and Parkinson disease, with a poor curative effect. PRIMARY DIAGNOSIS AND INTERVENTION: We diagnosed her with CTX and treated with chenodeoxycholic acid and clonazepam. CONCLUSION: The patient's condition considerably improved. This case could help avoid misdiagnosis and mistreatment in clinical practice.

The Last Straw: How Stress Can Unmask Parkinson's Disease.

We discuss two people with Parkinson's disease (PD), in whom tremor manifested directly following a severely stressful event. Both were initially misdiagnosed with a functional neurological disorder. These stories highlight that stress can trigger the onset of clinical manifestations of PD, by unveiling an underlying disease that had been unfolding for many years. Thus, the sudden symptom onset after a stressful event is not unique to functional disorders, and may lead to avoidable feelings of guilt if people wrongly attribute PD to this event. It remains unclear what mechanism explains this phenomenon, and why symptoms persist after the stressful event has passed.

Analysis of gait characteristics and related factors in patients with Parkinson's disease based on wearable devices.

BACKGROUND: Postural instability and gait disorder dominant (PIGD) is one of the most common disabling symptoms of Parkinson's disease (PD), which seriously affects patients' quality of life. Therefore, it is essential to identify PIGD and develop targeted interventions to reduce the risk of PIGD in PD patients. AIM: This study aimed to investigate the gait characteristics of PD patients based on wearable devices and to establish a predictive model for their related influencing factors. METHODS: The retrospective medical records of patients from January 2020 to September 2023 were collected, including 159 patients with PD (divided into PIGD [n = 73] and non-PIGD [n = 86] groups) and 200 healthy patients (as the healthy control group). Information from social demographic data, a blood test, scale scores, gait analysis based on wearable devices, white matter lesions, and the Fazekas scale was extracted and analyzed. RESULTS: Compared with the healthy control group, the mean step length, mean rate, mean angular velocity, and step length were lower in the PD group, while the mean steps were higher in the turning test. The incidence of PIGD was 46% in PD patients, and PD patients with the non-tremor onset mode were more likely to develop PIGD than those with the tremor onset mode. Compared to the non-PIGD group, the PIGD group showed more serious gait problems in different experimental tasks and had a higher Hoehn and Yahr (H-Y) stage, Hamilton Anxiety Scale (HAMA) score, Hamilton Depression Scale score, periventricular white matter (PVWM) score, deep white matter score, and Fazekas scale score, but they had lower hemoglobin levels, D-dimer levels, Tinetti Balance scores, Tinetti Gait scores, Berg Balance Scale scores, and Mini-Mental State Examination (MMSE) scores. Logistic regression analysis showed that the MMSE score was negatively correlated with the occurrence of PIGD, while the HAMA score, H-Y stage, PVWM score, and non-tremor form of onset were positively correlated with the occurrence of PIGD CONCLUSION: The incidence of gait disorder in PD patients is higher than that in the normal population. Moreover, cognitive dysfunction, anxiety state, H-Y stage, PVWM score, and the non-tremor mode of onset can be considered independent risk factors for PIGD.

Flapping Tremor: Unraveling Asterixis-A Narrative Review.

Asterixis is a subtype of negative myoclonus characterized by brief, arrhythmic lapses of sustained posture due to involuntary pauses in muscle contraction. We performed a narrative review to characterize further asterixis regarding nomenclature, historical aspects, etiology, pathophysiology, classification, diagnosis, and treatment. Asterixis has been classically used as a synonym for negative myoclonus across the literature and in previous articles. However, it is important to distinguish asterixis from other subtypes of negative myoclonus, for example, epileptic negative myoclonus, because management could change. Asterixis is not specific to any pathophysiological process, but it is more commonly reported in hepatic encephalopathy, renal and respiratory failure, cerebrovascular diseases, as well as associated with drugs that could potentially lead to hyperammonemia, such as valproic acid, carbamazepine, and phenytoin. Asterixis is usually asymptomatic and not spontaneously reported by patients. This highlights the importance of actively searching for this sign in the physical exam of encephalopathic patients because it could indicate an underlying toxic or metabolic cause. Asterixis is usually reversible upon treatment of the underlying cause.