Holmes tremor: Clinical description, lesion localization, and treatment in a series of 29 cases

OBJECTIVE

To describe the clinical features, etiology, findings from neuroimaging, and treatment results in a series of 29 patients with Holmes tremor (HT).

METHODS

A retrospective study was performed based on review of medical records and videos of patients with HT diagnosis.

RESULTS

A total of 16 women and 13 men were included. The mean age at the moment of CNS insult was 33.9 ± 20.1 years (range 8-76 years). The most common causes were vascular (48.3%), ischemic, or hemorrhagic. Traumatic brain injury only represented 17.24%; other causes represented 34.5%. The median latency from lesion to tremor onset was 2 months (range 7 days-228 months). The most common symptoms/signs associated with HT were hemiparesis (62%), ataxia (51.7%), hypoesthesia (27.58%), dystonia (24.1%), cranial nerve involvement (24.1%), and dysarthria (24.1%). Other symptoms/signs were vertical gaze disorders (6.8%), bradykinesia/rigidity (6.8%), myoclonus (3.4%), and seizures (3.4%). Most of the patients had lesions involving more than one area. MRI showed lesions in thalamus or midbrain or cerebellum in 82.7% of the patients. Levodopa treatment was effective in 13 out of 24 treated patients (54.16%) and in 3 patients unilateral thalamotomy provided excellent results.

CONCLUSIONS

The most common causes of HT in our series were vascular lesions. The most common lesion topography was mesencephalic, thalamic, or both. Treatment with levodopa and thalamic stereotactic lesional surgery seems to be effective.

Psychiatric comorbidities in patients from seven families with autosomal dominant cortical tremor, myoclonus, and epilepsy

OBJECTIVE

The objective of this report was to assess the psychiatric comorbidity in a group of patients affected by autosomal dominant cortical tremor, myoclonus, and epilepsy (ADCME).

METHODS

Reliable and validated psychodiagnostic scales including the BDI (Beck Depression Inventory), STAI-Y1 and 2 (State-Trait Anxiety Inventory - Y; 1 and 2), MMPI-2 (Minnesota Multiphasic Personality Inventory - 2), and QoLIE-31 (Quality of Life in Epilepsy Inventory - 31) were administered to 20 patients with ADCME, 20 patients with juvenile myoclonic epilepsy (JME), and 20 healthy controls.

RESULTS

There was a higher prevalence of mood disorders in patients with ADCME compared to patients with JME and healthy controls, particularly depression (p=0.035 and p=0.017, respectively) and state anxiety (p=0.024 and p=0.019, respectively). Trait anxiety was not different from JME (p=0.102) but higher than healthy controls (p=0.017). The myoclonus score positively correlated with both state (rho: 0.58, p=0.042) and trait anxiety (rho: 0.65, p=0.011). These psychiatric features were also often associated with pathological traits of personality: paranoid (OR: 25.7, p=0.003), psychasthenia (OR: 7.0, p=0.023), schizophrenia (OR: 8.5, p=0.011), and hypomania (OR: 5.5, p=0.022). Finally, in patients with ADCME, decreased quality of life correlated with these psychiatric symptoms.

SIGNIFICANCE

Patients with ADCME show a significant psychiatric burden that impairs their quality of life. A comprehensive psychiatric evaluation should be offered at the time of diagnosis to detect these comorbidities and to treat them.

Environmental exposure to manganese in air: Associations with tremor and motor function

BACKGROUND

Manganese (Mn) inhalation has been associated with neuropsychological and neurological sequelae in exposed workers. Few environmental epidemiologic studies have examined the potentially neurotoxic effects of Mn exposure in ambient air on motor function and hand tremor in adult community residents. Mn exposed residents were recruited in two Ohio towns: Marietta, a town near a ferro-manganese smelter, and East Liverpool, a town adjacent to a facility processing, crushing, screening, and packaging Mn products.

METHODS

Chronic (≥ 10 years) exposure to ambient air Mn in adult residents and effects on neuropsychological and neurological outcomes were investigated. Participants from Marietta (n=100) and East Liverpool (n=86) were combined for analyses. AERMOD dispersion modeling of fixed-site outdoor air monitoring data estimated Mn inhalation over a ten year period. Adult Mn-exposed residents' psychomotor ability was assessed using Finger Tapping, Hand Dynamometer, Grooved Pegboard, and the Computerized Adaptive Testing System (CATSYS) Tremor system. Bayesian structural equation modeling was used to assess associations between air-Mn and motor function and tremor.

RESULTS

Air-Mn exposure was significantly correlated in bivariate analyses with the tremor test (CATSYS) for intensity, center frequency and harmonic index. The Bayesian path analysis model showed associations of air-Mn with the CATSYS non-dominant center frequency and harmonic index; while the Bayesian structural equation model revealed associations between air-Mn and lower Finger Tapping scores. Household income was significantly associated with motor dysfunction but not with tremor.

CONCLUSION

Tremor and motor function were associated with higher exposure to airborne Mn.

Prevalence and characteristics of tremor in the NARCOMS multiple sclerosis registry: a cross-sectional survey

OBJECTIVES

(1)To describe the prevalence and severity of tremor in patients with multiple sclerosis (MS) registered within a large North American MS registry; (2) to provide detailed descriptions on the characteristics and severity of tremor in a subset of registrants and (3) to compare several measures of tremor severity for strength of agreement.

SETTING

The North American Research Committee on MS (NARCOMS) registry.

PARTICIPANTS

Registrants of NARCOMS reporting mild or greater tremor severity.

OUTCOME MEASURES

We determined the cross-sectional prevalence of tremor in the NARCOMS registry over three semiannual updates between fall 2010 and fall 2011. A subset of registrants (n=552) completed a supplemental survey providing detailed descriptions of their tremor. Outcomes included descriptive characteristics of their tremors and correlations between outcome measures to determine the strength of agreement in assessing tremor severity.

RESULTS

The estimated prevalence of tremor in NARCOMS ranged from 45% to 46.8%, with severe tremor affecting 5.5-5.9% of respondents. In the subset completing the supplemental survey, mild tremor severity was associated with younger age of MS diagnosis and tremor onset than those with moderate or severe tremor. However, tremor severity did not differ by duration of disease or tremor. Respondents provided descriptions of tremor symptoms on the Clinical Ataxia Rating Scale, which had a moderate to good (ρ=0.595) correlation with the Tremor Related Activities of Daily Living (TRADL) scale. Objectively scored Archimedes' spirals had a weaker (ρ=0.358) correlation with the TRADL. Rates of unemployment, disability and symptomatic medication use increased with tremor severity, but were high even among those with mild tremor.

CONCLUSIONS

Tremor is common among NARCOMS registrants and severely disabling for some. Both ADL-based and symptom-descriptive measures of tremor severity can be used to stratify patients.

Motor systems and postural instability

Acute alcohol intoxication and chronic alcohol dependence alter the neurologic control of posture and motor function. Ethanol delays the conduction of electric signals from the central nervous system to the muscles controlling posture and impairs the integration of sensory inputs required for maintaining vertical stance. Consequently, alcohol intoxication delays the ability to detect postural changes and enact the appropriate response. Common signs of acute alcohol intoxication include spinocerebellar and vestibulocerebellar ataxia, oculomotor changes, and increased reliance on visuospatial clues. Chronic alcoholism results in postural tremors and excessive sway during quiet stance that can persist even after sobriety is achieved. Underlying neurologic changes due to chronic alcoholism have been found to be associated with these characteristic postural changes and include decreased volume of the anterior superior vermis of the cerebellum, decreased connectivity within the corpus callosum, and overall cortical atrophy. Severity of motor impairments and other symptoms from alcoholism relate to a variety of factors, including duration of alcoholism, age, sex, and other health determinants and comorbidities. Imaging studies highlight the potential for partial recovery from neurologic and motor deficits caused by alcoholism. Emerging evidence on the motor and neurologic changes caused by alcohol dependence may allow for improved treatment and prevention of the morbidities associated with alcoholism.

Is action tremor in Parkinson's disease related to resting tremor?

OBJECTIVE

Action tremor (AT) and resting tremor (RT) have been widely cited in many studies with Parkinson's disease (PD) patients, but studies looking at the association between the two tremor types are few and show inconsistent results. This study will look at the prevalence and association of AT and RT in a large sample of idiopathic PD patients, and will put the results into context with the literature.

METHODS

A retrospective chart review analysis of 332 patients with idiopathic PD was performed. Prevalence rates of particular tremor types were noted. The presence of AT was analyzed relative to the presence and severity of RT.

RESULTS

Nearly all individuals with AT also had RT. The concurrence of the two tremor types was found to be highly significant by statistical analysis (P < 0.0001). The severity of RT, measured by its laterality, may also be of importance, albeit to a much smaller extent if at all. Neither presence of tremor nor type of tremor present was influenced by patient gender, age, or Hoehn and Yahr stage of PD.

CONCLUSIONS

The results indicate that AT has extensive presence in PD. This and its seemingly close relationship to RT suggest that AT may be considered a variant of RT, particularly in PD patients. The degree of association between RT and AT needs to be further analyzed in PD, as well as in essential tremor (ET) and ET-PD.

Cerebellar learning distinguishes inflammatory neuropathy with and without tremor

OBJECTIVES

This study aims to investigate if patients with inflammatory neuropathies and tremor have evidence of dysfunction in the cerebellum and interactions in sensorimotor cortex compared to nontremulous patients and healthy controls.

METHODS

A prospective data collection study investigating patients with inflammatory neuropathy and tremor, patients with inflammatory neuropathy without tremor, and healthy controls on a test of cerebellar associative learning (eyeblink classical conditioning), a test of sensorimotor integration (short afferent inhibition), and a test of associative plasticity (paired associative stimulation). We also recorded tremor in the arms using accelerometry and surface EMG.

RESULTS

We found impaired responses to eyeblink classical conditioning and paired associative stimulation in patients with neuropathy and tremor compared with neuropathy patients without tremor and healthy controls. Short afferent inhibition was normal in all groups.

CONCLUSIONS

Our data strongly suggest impairment of cerebellar function is linked to the production of tremor in patients with inflammatory neuropathy.

[Alzheimer's disease and fragile X syndrome: the Wnt/ß-catenin pathway as a common biological mechanism]

INTRODUCTION

Various disorders affecting the canonical Wnt/ß-catenin signalling pathway have been related to the activation or inactivation of oncogenes and tumour suppressor genes that give rise to a number of well-defined neoplasias, as well as several genes involved in a growing group of complaints, including Alzheimer's disease (AD) and fragile X syndrome (FXS).

AIM

To examine the Wnt/ß-catenin signalling pathway as a possible common biological mechanism involved in the origin and development of neurodegenerative conditions and its relationship with cancer.

DEVELOPMENT

We review the most recent biomedical literature dealing with the Wnt/ß-catenin signalling pathway and its participation in the genesis of complaints such as AD and FXS. An analysis is also conducted to determine the role that this metabolic pathway might play in explaining the lowered risk of developing cancer displayed by these patients.

CONCLUSIONS

The evidence found suggests that the Wnt/ß-catenin pathway could be regulating a set of genes linked with the control of the cell cycle and apoptosis. This would give rise to a metabolic state in which, in conditions such as AD and FXS, the cells would be more likely to undergo apoptosis than initiate mitosis, which would in turn account for the reduced risk of developing cancer.

[Essential tremor and Parkinson's disease: are they associated?]

INTRODUCTION

There is now growing evidence that essential tremor and Parkinson's disease are related.

AIM

To present the main findings from epidemiologic, genetic, clinical, imaging and pathologic studies, contrasting evidences for and against an association between essential tremor and Parkinson's disease.

DEVELOPMENT

We include a complete update of the latest findings regarding the overlap between these two disorders. There is current evidence that a history of essential tremor may herald the onset of Parkinson's disease in a subset of patients. Furthermore, the fact that the risk of essential tremor is significantly increased in relatives of patients with Parkinson's disease suggests the possibility that both conditions are genetically related, probably sharing common hereditary predisposition. Dopaminergic deficit among essential tremor patients in functional imaging studies and recent pathological studies describing Lewy bodies in some essential tremor patients, support further evidence for an overlap between both conditions, at least in a subset of patients.

CONCLUSION

The convergence of all the reviewed data suggests the possible existence of a mixed essential tremor-Parkinson's disease phenotype in some patients. However, further studies are needed to better understand this phenotype.

Prepulse inhibition in patients with fragile X-associated tremor ataxia syndrome

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late onset neurodegenerative disorder that affects carriers of the fragile X premutation, typically after age 50. Common symptoms include intention tremor, ataxia, neuropathy, autonomic dysfunction, cognitive decline, and dementia. The objectives of this study were to determine if patients with FXTAS have altered prepulse inhibition (PPI; a measure of sensorimotor gating), and to study possible correlations between PPI, molecular status, and cognitive performance. A passive acoustic PPI paradigm was applied in 163 subjects; 121 carriers of the fragile X premutation, and 42 healthy controls. There were significant differences in PPI between premutation carriers with FXTAS and controls at PPI 60 ms, and at 120 ms. This effect was more prominent in the male FXTAS patients. There was a tendency to an impaired PPI in female premutation carriers at the 120 ms condition. There was a significant correlation between the PPI deficit and a higher CGG repeat number. The results show an impairment in sensorimotor gating processes in male carriers of the fragile X premutation, which is more prominent in patients with FXTAS.

[Orthostatic tremor: an enigmatic condition]

INTRODUCTION

Orthostatic tremor is a rare kind of tremor which is clinically characterised by a feeling of instability or being about to fall that is experienced on standing up, which disappears or improves on walking and is absent when sitting or lying down.

AIM

To shed light on the main features of this tremor syndrome.

DEVELOPMENT

First, its clinical spectrum is defined, with emphasis on the key characteristics that enable us to make an initial approximation to its syndromes. Then the main neurophysiological features that make up the electromyographic profile of orthostatic tremor are described. Finally, the pathophysiological hypotheses regarding the genesis of this kind of tremor are addressed and the therapeutic options currently available are described.

CONCLUSIONS

The convergence of all the data reviewed provides a complete, critical analysis of this enigmatic motor disorder, thus allowing a rigorous approach to its main characteristics, which makes both its clinical recognition and its therapeutic management easier.

Fragile X-associated tremor/ataxia syndrome

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an under-recognized disorder that is a significant cause of late-adult-onset ataxia. The etiology is expansion of a trinucleotide repeat to the premutation range (55-200 CGG repeats) in the fragile X mental retardation 1 (FMR1) gene. Expansion to >200 CGGs causes fragile X syndrome, the most common heritable cause of cognitive impairment and autism. Core features of FXTAS include progressive action tremor and gait ataxia; with frequent, more variable features of cognitive decline, especially executive dysfunction, parkinsonism, neuropathy, and autonomic dysfunction. MR imaging shows generalized atrophy and frequently abnormal signal in the middle cerebellar peduncles. Autopsy reveals intranuclear inclusions in neurons and astrocytes and dystrophic white matter. FXTAS is likely due to an RNA toxic gain-of-function of the expanded-repeat mRNA. The disorder typically affects male premutation carriers over age 50, and, less often, females. Females also are at increased risk for primary ovarian insufficiency, chronic muscle pain, and thyroid disease. Treatment targets specific symptoms, but progression of disability is relentless. Although the contribution of FXTAS to the morbidity and mortality of the aging population requires further study, the disorder is likely the most common single-gene form of tremor and ataxia in the older adult population.

Tremor and β(2)-adrenergic agents: is it a real clinical problem?

Tremor is one of the most characteristic adverse effects following administration of β(2)-adrenergic agonists. It is reported by around 2-4% of patients with asthma taking a regular β(2)-adrenergic agonist and is induced by both short-acting and long-acting agents. Tremor associated with β(2)-adrenergic agonists is dose-related and may occur more commonly with oral dosing. The exact mechanism for tremor induction by β(2)-adrenergic agonists is still unknown, but there is some evidence that β(2)-adrenergic agonists act directly on muscle. An early explanation of the tremor was that β(2)-adrenoceptor stimulation shortens the active state of skeletal muscle, which leads to incomplete fusion and reduced tension of tetanic contractions. More recently, tremor has been correlated closely with hypokalaemia. A possible diverse impact of different modes of administration of β(2)-adrenergic agonists on tremorogenic responses has been suggested but solid evidence is still lacking. In any case, the desensitization of β(2)-adrenoceptors that occurs during the first few days of regular use of a β(2)-adrenergic agonist accounts for the commonly observed resolution of tremor after the first few doses. Therefore, tremor is not a really important adverse effect in patients under regular treatment with a β(2)-adrenergic agonist.

Quantitative analysis of tremors in welders

Background:

Workers chronically exposed to manganese in welding fumes may develop an extra-pyramidal syndrome with postural and action tremors.

Objectives:

To determine the utility of tremor analysis in distinguishing tremors among workers exposed to welding fumes, patients with Idiopathic Parkinson’s Disease (IPD) and Essential Tremor (ET).

Methods:

Retrospective study of recorded tremor in subjects from academic Movement Disorders Clinics and Welders. Quantitative tremor analysis was performed and associated with clinical status.

Results:

Postural tremor intensity was increased in Welders and ET and was associated with visibly greater amplitude of tremor with arms extended. Mean center frequencies (Cf) of welders and patients with ET were significantly higher than the mean Cf of PD subjects. Although both the welders and the ET group exhibited a higher Cf with arms extended, welders could be distinguished from the ET subjects by a significantly lower Cf of the rest tremor than that measured in ET subjects.

Conclusions:

In the context of an appropriate exposure history and neurological examination, tremor analysis may be useful in the diagnosis of manganese-related extra-pyramidal manifestations.

Neuromotor effects of short-term and long-term exposures to trichloroethylene in workers

BACKGROUND

Health effects of long-term exposure to organic solvents at low levels are a major concern in industrialized countries. To assess the neuromotor impact of trichloroethylene objectively, static postural sway and hand tremor parameters, along with urinary trichloroethanol (TCOH) and trichloroacetic acid (TCAA) levels, were investigated in 57 workers without obvious neurological disorders and 60 control subjects.

METHODS

The workers had been occupationally exposed to trichloroethylene for 0.1-37 years. The cumulative exposure index (CEI) was calculated from their occupational history and total trichloro-compounds (TCOH + TCAA).

RESULTS

Median levels in the workers were 1.7 mg/L for TCOH and 2.5 mg/L for TCAA, and the maximum ambient trichloroethylene concentration was estimated to be <22 ppm from the previously reported equation using TCOH + TCAA. Sway parameters with eyes open and tremor intensity in dominant hand were significantly larger in the exposed workers than in the control subjects when adjusting for possible confounders. A significant dose-effect association was seen between two sway parameters and urinary TCOH level in the workers. Tremor intensities in non-dominant hand differed significantly among three groups of the workers divided according to the CEI.

CONCLUSIONS

These findings suggest that trichloroethylene exposure, even at low levels of less than the short-term exposure limit by the ACGIH, can affect the neuromotor function of workers. The postural instability appears to result from recent exposure, and the increased tremor may occur due to short-term and long-term exposures. Hereafter, such objective measures, along with subjective symptoms, should be carefully used for the occupational exposure limit setting.

Indole-diterpenes and ergot alkaloids in Cynodon dactylon (Bermuda grass) infected with Claviceps cynodontis from an outbreak of tremors in cattle

Tremorgenic syndromes in mammals are commonly associated with indole-diterpenoid alkaloids of fungal origin. Cattle are sometimes affected by tremors (also called "staggers") when they graze on toxic grass pastures, and Bermuda grass ( Cynodon dactylon , kweek) has been known to be associated with tremors for several decades. This study reports the identification of paspalitrems and paspaline-like indole-diterpenes in the seedheads of Claviceps cynodontis -infected Bermuda grass collected from a pasture that had caused a staggers syndrome in cattle in South Africa and thereby links the condition to specific mycotoxins. The highest concentration (about 150 mg/kg) was found for paspalitrem B. Ergonovine and ergine (lysergic acid amide), together with their C-8 epimers, were found to co-occur with the indole-diterpenes at concentrations of about 10 microg/kg. The indole-diterpene profile of the extract from the ergotized Bermuda grass was similar to that of Claviceps paspali sclerotia. However, the C. paspali sclerotia contained in addition agroclavine and elymoclavine. This is the first study linking tremors associated with grazing of Bermuda grass to specific tremorgenic indole-diterpenoid mycotoxins.

[Fragile X-associated tremor/ataxia syndrome]

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a recently characterized adult onset neurodegenerative disorder affecting both male and female (male>female) carriers of premutation CGG repeat expansions of the FMR1 gene. Onset typically occurs after the age of 50 years with a lifetime risk of FXTAS in males of about 1 in 3,000-6,000. Core features include progressive gait ataxia and cerebellar tremor with associated features of cognitive deficits, peripheral neuropathy and dysautonomia. The diagnosis of FXTAS is established based on clinical presentation, cerebral imaging and genetic testing. Due to the still low level of awareness of FXTAS and its variable clinical picture FXTAS is substantially underdiagnosed. However, confirming the diagnosis is essential for genetic counseling of the patients as the offspring are at risk for fragile X syndrome, premature ovarian insufficiency (POI) or FXTAS. Furthermore, many features of FXTAS can be treated symptomatically.

Neurologic complications after renal transplant

OBJECTIVES

Neurologic complications are a significant cause of morbidity and mortality in patients who undergo transplants. We sought to evaluate the nature and incidence of neurologic complications in patients undergoing a renal transplant.

PATIENTS AND METHODS

Between January 2005 and December 2007, 132 adults (35 women, 97 men; mean age, 34.32 -/+ 0.90 years) underwent a renal transplant at our institution. Associated comorbid medical conditions, presenting neurologic symptoms, and type of immunosuppression were obtained from patients' medical records.

RESULTS

Major indications for renal transplant were hypertensive nephropathy (14.4%), vesicoureteral reflux (11.4%), and idiopathic causes (21.2%). Mean follow-up was 17.26 -/+ 0.89 months (range, 2 weeks to 40 months). Twenty neurologic complications were found in 18 patients (6 women, 12 men; mean age, 33.83 -/+ 2.37 years). Presenting symptoms included posterior leukoencephalopathy syndrome, 1 (5.6%); cephalgia, 10 (55.6%); cerebral infarcts, 2 (11.1%); seizure, 3 (16.7%); tremor, 2 (11.1%); encephalopathy, 1 (5.6%); and sinus thrombosis, 1 (5.6%). Immunosuppressive agents were the primary cause of 16 of the 20 neurologic complications. Effectiveness and complications of cyclosporinewere screened for a total of 1858.50 months, tacrolimus for 853.50 months, and sirolimus for 620 months; 50.2% of the neurologic complications appeared during the first 3 months after transplant; the blood level of immunosuppressive medications did not need to be higher than normal in every case.

DISCUSSION

In addition to cyclosporine and tacrolimus, we suggest (for the first time) sirolimus as a cause of neurocomplications after renal transplant.

Evaluation of the Unified Wilson's Disease Rating Scale (UWDRS) in German patients with treated Wilson's disease

Wilson's disease (WD) is an inherited autosomal-recessive disorder of copper metabolism characterized by a wide variety of neurological, hepatic, and psychiatric symptoms. The aim of the present study was the development and evaluation of a clinical rating scale, termed Unified Wilson's Disease Rating Scale (UWDRS), to assess the whole spectrum of clinical symptoms in WD. Altogether 107 patients (mean age 37.6 +/- 11.9 years; 46 male, 61 female) with treated WD participated in the study. Cronbach's alpha as a measure of the internal consistency for the entire scale was 0.92, whereas the intraclass correlation coefficient (ICC) was 0.98 (confidence interval (CI(95%)) 0.97-0.99), indicating an excellent interrater reliability as determined in 32 patients. Besides the total score was significantly correlated with the earning capacity of the patients as indicated by an estimated Spearman's rho approximately 0.54 (CI(95%) 0.40-0.69, P < 0.001). In summary, the UWDRS appears to be a promising tool to assess the disease severity in WD. Its usefulness in clinical research and drug trials should be further addressed.

Tremor frequency profile as a function of level of mental retardation

The characteristic slowness of movement initiation and execution in adult individuals with mental retardation may be driven by the slower frequency profile of the dynamics of the system. To investigate this hypothesis, we examined the resting and postural finger tremor frequency profile (single and dual limb) of adults as a function of level of mental retardation (moderate, severe, profound). There was a progressive increase in the contribution of slow frequency components to the enhanced amplitude of tremor as a function of mental retardation, particularly in the group with profound mental retardation. Findings support the hypothesis of mental retardation inducing a slower frequency to the system dynamics that may fundamentally drive the characteristic slowness of movement behavior.