A Treatable Rare Cause of Progressive Ataxia and Palatal Tremor

Background

Cerebrotendinous xanthomatosis is a rare autosomal recessive neurometabolic disorder characterized by chronic diarrhea, tendon xanthomas, juvenile cataracts, and neurological symptoms.

Case Report

An adult patient with cerebrotendinous xanthomatosis exhibited ataxia and palatal tremor in the absence of tendon xanthomas and cataracts.

Discussion

The importance of this case resides on the fact that cerebrotendinous xanthomatosis should be considered as a possible etiology of the syndrome of progressive ataxia with palatal tremor, even in the absence of tendon xanthomas and cataracts. Early diagnosis is critical to the institution of specific treatment with chenodeoxycholic acid.

Challenges in PD Patient Management After DBS: A Pragmatic Review

BACKGROUND

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) or internal globus pallidus (GPi) represents an effective and universally applied therapy for Parkinson's disease (PD) motor complications. However, certain procedure-related problems and unrealistic patient expectations may detract specialists from indicating DBS more widely despite significant clinical effects.

METHODS

This review provides a pragmatic educational summary of the most conflicting postoperative management issues in patients undergoing DBS for PD.

RESULTS

DBS in PD has been associated with certain complications and post-procedural management issues, which can complicate surgical outcome interpretation. Many PD patients consider DBS outcomes negative due to unfulfilled expectations, even when significant motor symptom improvement is achieved. Speech, gait, postural stability, and cognition may worsen after DBS and body weight may increase. Although DBS may induce impulse control disorders in some cases, in others, it may actually improve them when dopamine agonist dosage is reduced after surgery. However, apathy may also arise, especially when dopaminergic medication tapering is rapid. Gradual loss of response with time suggests disease progression, rather than the wearing off of DBS effects. Furthermore, implantable pulse generator expiration is considered a movement disorder emergency, as it may worsen parkinsonian symptoms or cause life-threatening akinetic crises due to malignant DBS withdrawal syndrome.

CONCLUSION

Major unsolved issues occurring after DBS therapy preclude complete patient satisfaction. Multidisciplinary management at experienced centers, as well as careful and comprehensive delivery of information to patients, should contribute to make DBS outcome expectations more realistic and allow post procedural complications to be better accepted.

Diagnostic Value of Combined Acute Levodopa Challenge and Olfactory Testing to Predict Parkinson's Disease

BACKGROUND

The diagnosis of Parkinson's disease (PD) can be challenging early in the disease course, when motor features are subtle. The objective of this study was to explore the diagnostic value of combining acute levodopa challenge and olfactory testing to predict PD.

METHODS

Data from 210 patients with a recent onset of parkinsonism who had at least 2 years of follow-up and underwent acute levodopa challenge for the clinical prediction of long-term dopaminergic response and had olfactory testing with Sniffin' Sticks Test were evaluated. Single and combined diagnostic measures were analyzed.

RESULTS

After 2 years of follow-up, a PD diagnosis was confirmed in 157 patients who fulfilled United Kingdom Parkinson's Disease Society Brain Bank criteria and was ruled out in 53. Sensitivity and specificity of acute levodopa challenge to predict PD diagnosis were 0.71 and 0.94, respectively. Sensitivity and specificity of olfactory tests were calculated according to the total olfactory score for hyposmia (0.61 and 0.77 respectively), the hyposmia identification subscore (0.63 and 0.74, respectively), and the anosmia score (0.40 and 0.85, respectively). The best combination identified was response to acute levodopa challenge together with hyposmia according to the total olfactory score (sensitivity, 0.90; specificity, 0.74; positive predictive value, 0.91; negative predictive value, 0.72; accuracy, 0.86).

CONCLUSION

The combination of response to acute levodopa challenge with hyposmia according to the total olfactory score improved sensitivity for the early diagnosis of PD.

Is tremor related to celiac disease?

Neurological features in celiac disease (CD) are not rare (5%-36%), but tremor is scarcely described. Subjects with CD and healthy controls completed an online survey using WHIGET tremor rating scale. One thousand five hundred and twelve subjects completed the survey, finally 674 CD patients and 290 healthy subjects were included. A higher prevalence of tremor in CD patients was observed in comparison to controls (28% vs 14%, P < 0.001). Frequency of family history of tremor in CD patients with and without tremor was 25% and 20% (P = 0.2), while in the control group it was 41% and 10% (P < 0.001). Controls with tremor showed a higher frequency of family history of tremor when compared to CD patients with tremor (41.5% vs 24.6%, P = 0.03). The results suggested that tremor in CD might be more frequent and possibly related to the disease itself and not due to associated essential tremor.

Self-Assessment of Disability in Parkinson's Disease: The MDS-UPDRS Part II Versus Clinician-Based Ratings

Background

Parkinson's disease (PD) is characterized by motor and nonmotor symptoms that progress with time, causing disability. The performance of a disease-specific, self-applied tool for assessing disability, the MDS-UPDRS Part II, is tested against generic and rater-based rating scales.

Methods

An international, cross-sectional, observational study was performed. Patients were assessed with the Hoehn and Yahr (HY) and five disability measures: MDS-UPDRS Part II, Schwab and England Scale (S&E), Clinical Impression of Severity Index-PD (CISI-PD) Disability item, Barthel Index (BI), and Rapid Assessment of Disability Scale (RADS). Data analysis included correlation coefficients, Mann-Whitney and Kruskal-Wallis tests, and intraclass-correlation coefficient for concordance.

Results

The sample was composed of 451 patients, 55.2% men, with a mean age of 65.06 years (SD = 10.71). Disability rating scales correlated from |0.75| (CISI-PD Disability with BI) to 0.87 (MDS-UPDRS Part II with RADS). In general, MDS-UPDRS Part II showed high correlation coefficients with clinical variables and satisfactory concordance with the rest of disability measures, with ICC ranging from 0.83 (with BI) to 0.93 (with RADS). All disability rating scales showed statistical significant differences in the sample grouped by sex, age, disease duration, and severity level.

Conclusions

The MDS-UPDRS Part II showed an appropriate performance to assess disability in PD, even better than some rater-based, generic or specific, scales applied in this study.

How Do I Examine Postural Disorders in Parkinson's Disease?

Postural abnormalities in Parkinson's disease (PD) are considered the rule more than the exception and are disabling complications of the disease. These deformities include camptocormia, antecollis, Pisa syndrome, and scoliosis. Evidence to date suggests that postural deformities have a multifactorial pathophysiology, including muscular rigidity, axial dystonia, weakness due to myopathy, body scheme defects due to centrally impaired proprioception, and structural changes in the spine. Antecollis in parkinsonian disorders refers to a forward flexion of the head and neck. It is usually mild in severity and may be considered part of the stooped posture in patients with PD. Some authors that suggest the term antecollis should only be used in patients with at least a minimum of 45 degrees of thoracolumbar flexion. Neither camptocormia nor Pisa syndrome can be evaluated without taking into account the presence or absence of scoliosis. In this regard, the rotating component of the spine and its behavior in the supine position give important clues for a correct diagnosis. In some cases, X-rays in the standing and supine positions are necessary. The presence of marked camptocormia requires a minimum of flexion in the sagittal plane originating in the thoracolumbar spine greater than 45 degrees, with an almost complete resolution in the supine position. Pisa syndrome requires a minimum of 10 degrees of lateral flexion and is almost completely alleviated by passive mobilization or supine positioning. A certain degree of scoliosis is expected in most parkinsonian patients; therefore, both camptocormia and Pisa syndrome do not generally present as pure syndromes.

Facial tremors in patients with and without parkinsonism

Facial (lip and jaw) tremors can be an early sign of Parkinson's disease (PD), essential tremor and other parkinsonisms. Its response to acute dopaminergic therapy and further predictive clinical diagnosis has not been previously addressed. The aim of this study was to evaluate facial tremors response to acute dopaminergic therapy and further predictive value for clinical diagnosis. A retrospective review of medical records from patients with recent onset of facial tremor, with or without parkinsonism, submitted to acute levodopa challenge for clinical prediction of sustained long-term dopaminergic response was conducted. Twenty-eight out of 559 patients (5 %) had facial tremors, which responded to levodopa in 46 % of patients. Facial tremors response to acute levodopa challenge showed 92 % sensitivity and 93 % specificity to predict a final PD diagnosis. In PD patients, facial tremor magnitude of response to levodopa was not different from that of hand rest tremor (p = 0.8). Facial tremors, although infrequent, can be an early sign of PD. Positive response to acute levodopa challenge predicts long-term PD diagnosis.

Motor features in Parkinson's disease with normal olfactory function

BACKGROUND

Normosmic Parkinson's disease (PD) might be a unique clinical phenotype with a more benign course when compared with hyposmic PD.

OBJECTIVE

The objective of this study was to evaluate motor features and the acute levodopa response according to olfactory function.

METHODS

A total of 169 de novo PD patients that underwent olfactory testing and acute levodopa challenge for clinical prediction of sustained long-term dopaminergic response were evaluated.

RESULTS

The overall frequency of normosmia was 33%. Normosmic PD patients scored nonsignificantly different to hyposmic/anosmic patients on motor scale and on degree of improvement with levodopa. Motor scores at follow-up were comparable among groups.

CONCLUSIONS

Normal olfactory function is common in early PD and was not associated with a different motor phenotype when compared with PD patients with olfactory dysfunction. © 2016 International Parkinson and Movement Disorder Society.

Analysis of four scales for global severity evaluation in Parkinson's disease

Global evaluations of Parkinson’s disease (PD) severity are available, but their concordance and accuracy have not been previously tested. The present international, cross-sectional study was aimed at determining the agreement level among four global scales for PD (Hoehn and Yahr, HY; Clinical Global Impression of Severity, CGIS; Clinical Impression of Severity Index, CISI-PD; and Patient Global Impression of Severity, PGIS) and identifying which of them better correlates with itemized PD assessments. Assessments included additional scales for evaluation of the movement impairment, disability, affective disorders, and quality of life. Spearman correlation coefficients, weighted and generalized kappa, and Kendall’s concordance coefficient were used. Four hundred thirty three PD patients, 66% in HY stages 2 or 3, mean disease duration 8.8 years, were analyzed. Correlation between the global scales ranged from 0.60 (HY with PGIS) to 0.91 (CGIS with CISI-PD). Kendall’s coefficient of concordance resulted 0.76 (P<0.0001). HY and CISI-PD showed the highest association with age, disease duration, and levodopa-equivalent daily dose, and CISI-PD with measures of PD manifestations, disability, and quality of life. PGIS and CISI-PD correlated similarly with anxiety and depression scores. The lowest agreement in classifying patients as mild, moderate, or severe was observed between PGIS and HY or CISI-PD (58%) and the highest between CGIS and CISI-PD (84.3%). The four PD global severity scales agree moderately to strongly among them; clinician-based ratings estimate PD severity, as established by other measures, better than PGIS; and the CISI-PD showed the highest association with measures of impairment, disability, and quality of life.

The impact of emotional distress on motor blocks and festination in Parkinson's disease

Recent studies suggest that depression and anxiety in patients with Parkinson's disease may predispose them to freezing. Although festination is also frequent, the association with emotional disorders has not been examined. The aim of the authors was to clarify the association between freezing and festination with anxiety, depressive disorders, and emotional distress. The authors examined a consecutive series of 95 patients with Parkinson's disease using comprehensive psychiatric assessments and a new instrument specifically designed to assess the severity of freezing, festination, and emotional distress (Motor Blocks and Festination Scale). All patients were assessed with the Motor Blocks and Festination Scale, the Mini International Neuropsychiatric Interview, and scales to measure the severity of mood and anxiety disorders. A linear regression analysis showed that both motor blocks and festination were significantly associated with emotional distress and deficits on activities of daily living. Conversely, there was no significant association between motor blocks or festination and generalized anxiety disorder, panic disorder, agoraphobia, social phobia, or depression. Motor blocks and festination are significantly associated with emotional distress, but no significant associations were found with anxiety or affective disorders.

Neural code alterations and abnormal time patterns in Parkinson's disease

OBJECTIVE

The neural code used by the basal ganglia is a current question in neuroscience, relevant for the understanding of the pathophysiology of Parkinson's disease. While a rate code is known to participate in the communication between the basal ganglia and the motor thalamus/cortex, different lines of evidence have also favored the presence of complex time patterns in the discharge of the basal ganglia. To gain insight into the way the basal ganglia code information, we studied the activity of the globus pallidus pars interna (GPi), an output node of the circuit.

APPROACH

We implemented the 6-hydroxydopamine model of Parkinsonism in Sprague-Dawley rats, and recorded the spontaneous discharge of single GPi neurons, in head-restrained conditions at full alertness. Analyzing the temporal structure function, we looked for characteristic scales in the neuronal discharge of the GPi.

MAIN RESULTS

At a low-scale, we observed the presence of dynamic processes, which allow the transmission of time patterns. Conversely, at a middle-scale, stochastic processes force the use of a rate code. Regarding the time patterns transmitted, we measured the word length and found that it is increased in Parkinson's disease. Furthermore, it showed a positive correlation with the frequency of discharge, indicating that an exacerbation of this abnormal time pattern length can be expected, as the dopamine depletion progresses.

SIGNIFICANCE

We conclude that a rate code and a time pattern code can co-exist in the basal ganglia at different temporal scales. However, their normal balance is progressively altered and replaced by pathological time patterns in Parkinson's disease.

Management of constipation in Parkinson's disease

INTRODUCTION

Constipation is a frequent non-motor feature of Parkinson's disease (PD). It is the most common gastrointestinal symptom of the disease and it can precede motor symptoms by as much as 20 years. Constipation can produce discomfort and affect activities of daily living, productivity and quality of life, thus warranting early diagnosis and treatment.

AREAS COVERED

In this review, the safety and efficacy of traditional and novel strategies for constipation management will be discussed. A treatment algorithm for constipation in PD will be presented.

EXPERT OPINION

Polyethylene glycol and lubiprostone are first-line compounds recommended by evidence-based medicine guidelines for the treatment of constipation due to slow colonic transit in PD. Management of constipation secondary to defecatory dysfunction due to pelvic floor dyssynergia can be done by levodopa or apomorphine injections, botulinum toxin type A injection into the puborectalis muscle, and nonpharmacological interventions, like biofeedback therapy or functional magnetic stimulation, which showed some benefit in PD patients with constipation, but in general more extensive studies are warranted.

Multiple-time-scale framework for understanding the progression of Parkinson's disease

Parkinson's disease is marked by neurodegenerative processes that affect the pattern of discharge of basal ganglia neurons. The main features observed in the parkinsonian globus pallidus pars interna (GPi), a subdomain of the basal ganglia that is involved in the regulation of voluntary movement, are pathologically increased and synchronized neuronal activity. How these changes affect the implemented neuronal code is not well understood. Our experimental temporal structure-function analysis shows that in parkinsonian animals the rate-coding window of GPi neurons needed for the proper performance of voluntary actions is reduced. The model of the GPi network that we develop and discuss here reveals indeed that the size of the rate-coding window shrinks as the network activity increases and is expanded if the coupling strength among the neurons is increased. This leads to the novel interpretation that the pathological neuronal synchronization in Parkinson's disease in the GPi is the result of a collective attempt to counterbalance the shrinking of the rate-coding window due to increased activity in GPi neurons.