Objective: Parkinson’s disease (PD) is a progressive neurological disorder characterised by a large number of motor and non-motor features that can impact on function to a variable degree. This review describes the clinical characteristics of PD with emphasis on those features that differentiate the disease from other parkinsonian disorders. Methods: A MedLine search was performed to identify studies that assess the clinical characteristics of PD. Search terms included “Parkinson’s disease”, “diagnosis” and “signs and symptoms”. Results: Because there is no definitive test for the diagnosis of PD, the disease must be diagnosed based on clinical criteria. Rest tremor, bradykinesia, rigidity and loss of postural reflexes are generally considered the cardinal signs of PD. The presence and specific presentation of these features are used to differentiate PD from related parkinsonian disorders. Other clinical features include secondary motor symptoms (eg, hypomimia, dysarthria, dysphagia, sialorrhoea, micrographia, shuffling gait, festination, freezing, dystonia, glabellar reflexes), non-motor symptoms (eg, autonomic dysfunction, cognitive/neurobehavioral abnormalities, sleep disorders and sensory abnormalities such as anosmia, paresthesias and pain). Absence of rest tremor, early occurrence of gait difficulty, postural instability, dementia, hallucinations, and the presence of dysautonomia, ophthalmoparesis, ataxia and other atypical features, coupled with poor or no response to levodopa, suggest diagnoses other than PD. Conclusions: A thorough understanding of the broad spectrum of clinical manifestations of PD is essential to the proper diagnosis of the disease. Genetic mutations or variants, neuroimaging abnormalities and other tests are potential biomarkers that may improve diagnosis and allow the identification of persons at risk.

https://jnnp.bmj.com/content/jnnp/79/4/368.full.pdf

Parkinson’s disease: clinical features and diagnosis

This document presents the Movement Disorder Society Clinical Diagnostic Criteria for Parkinson's disease (PD). The Movement Disorder Society PD Criteria are intended for use in clinical research but also may be used to guide clinical diagnosis. The benchmark for these criteria is expert clinical diagnosis; the criteria aim to systematize the diagnostic process, to make it reproducible across centers and applicable by clinicians with less expertise in PD diagnosis. Although motor abnormalities remain central, increasing recognition has been given to nonmotor manifestations; these are incorporated into both the current criteria and particularly into separate criteria for prodromal PD. Similar to previous criteria, the Movement Disorder Society PD Criteria retain motor parkinsonism as the core feature of the disease, defined as bradykinesia plus rest tremor or rigidity. Explicit instructions for defining these cardinal features are included. After documentation of parkinsonism, determination of PD as the cause of parkinsonism relies on three categories of diagnostic features: absolute exclusion criteria (which rule out PD), red flags (which must be counterbalanced by additional supportive criteria to allow diagnosis of PD), and supportive criteria (positive features that increase confidence of the PD diagnosis). Two levels of certainty are delineated: clinically established PD (maximizing specificity at the expense of reduced sensitivity) and probable PD (which balances sensitivity and specificity). The Movement Disorder Society criteria retain elements proven valuable in previous criteria and omit aspects that are no longer justified, thereby encapsulating diagnosis according to current knowledge. As understanding of PD expands, the Movement Disorder Society criteria will need continuous revision to accommodate these advances.

/pdf/mds-clinical-diagnostic-criteria-for-parkinson-s-disease-74dzuucoq6.pdf

MDS clinical diagnostic criteria for Parkinson's disease

BACKGROUND: Neurostimulation of the subthalamic nucleus reduces levodopa-related motor complications in advanced Parkinson's disease. We compared this treatment plus medication with medical management. METHODS: In this randomized-pairs trial, we enrolled 156 patients with advanced Parkinson's disease and severe motor symptoms. The primary end points were the changes from baseline to six months in the quality of life, as assessed by the Parkinson's Disease Questionnaire (PDQ-39), and the severity of symptoms without medication, according to the Unified Parkinson's Disease Rating Scale, part III (UPDRS-III). RESULTS: Pairwise comparisons showed that neurostimulation, as compared with medication alone, caused greater improvements from baseline to six months in the PDQ-39 (50 of 78 pairs, P=0.02) and the UPDRS-III (55 of 78, P<0.001), with mean improvements of 9.5 and 19.6 points, respectively. Neurostimulation resulted in improvements of 24 to 38 percent in the PDQ-39 subscales for mobility, activities of daily living, emotional well-being, stigma, and bodily discomfort. Serious adverse events were more common with neurostimulation than with medication alone (13 percent vs. 4 percent, P<0.04) and included a fatal intracerebral hemorrhage. The overall frequency of adverse events was higher in the medication group (64 percent vs. 50 percent, P=0.08). CONCLUSIONS: In this six-month study of patients under 75 years of age with severe motor complications of Parkinson's disease, neurostimulation of the subthalamic nucleus was more effective than medical management alone. (ClinicalTrials.gov number, NCT00196911 [ClinicalTrials.gov].).

/pdf/a-randomized-trial-of-deep-brain-stimulation-for-parkinson-s-40jf18b006.pdf

A Randomized Trial of Deep-Brain Stimulation for Parkinson's Disease

Measuring Health: A Guide to Rating Scales and Questionnaires

The clinical diagnosis of Parkinson's disease rests on the identification of the characteristics related to dopamine deficiency that are a consequence of degeneration of the substantia nigra pars compacta. However, non-dopaminergic and non-motor symptoms are sometimes present before diagnosis and almost inevitably emerge with disease progression. Indeed, non-motor symptoms dominate the clinical picture of advanced Parkinson's disease and contribute to severe disability, impaired quality of life, and shortened life expectancy. By contrast with the dopaminergic symptoms of the disease, for which treatment is available, non-motor symptoms are often poorly recognised and inadequately treated. However, attention is now being focused on the recognition and quantitation of non-motor symptoms, which will form the basis of improved treatments. Some non-motor symptoms, including depression, constipation, pain, genitourinary problems, and sleep disorders, can be improved with available treatments. Other non-motor symptoms can be more refractory and need the introduction of novel non-dopaminergic drugs. Inevitably, the development of treatments that can slow or prevent the progression of Parkinson's disease and its multicentric neurodegeneration provides the best hope of curing non-motor symptoms.

https://www.thelancet.com/pdfs/journals/laneur/PIIS1474-4422(06)70373-8.pdf

Non-motor symptoms of Parkinson's disease: diagnosis and management

We describe a 62-year-old patient who presented with ataxia and dystonia with mild dementia and was shown at autopsy to have Creutzfeldt-Jakob's disease. Movement disorders may be the presenting feature of Creutzfeldt-Jakob's disease, and this entity should be considered in the differential diagnosis of an otherwise obscure movement disorder even when the typical electroencephalographic pattern is absent.

Creutzfeldt-Jakob's disease presenting with ataxia and a movement disorder

Restless legs syndrome (RLS), also known as Willis-Ekbom disease, is a common sensorimotor disorder that may be idiopathic (primary) or secondary to a diverse group of conditions. The pathophysiology of primary RLS is only partly understood, but a strong association with brain iron deficiency possibly resulting in impaired dopaminergic function has been recognized. Genomic studies have established a genetic basis for primary RLS as well, and at least 42% of people with primary RLS possess a first-degree relative with the disorder. Secondary RLS is often associated with renal insufficiency, pregnancy, iron deficiency anemia, diabetic neuropathy, and Parkinson's disease. Approximately one-fourth of pregnant women experience RLS, with more intense symptoms experienced during the third trimester, and resolution of symptoms typically occurring within a few months after delivery, though RLS may resolve as early as 2 weeks after delivery. Restless legs syndrome is associated with increased prevalence of mood disturbances, sleep disturbances, and an impaired quality of life. The diagnosis of RLS involves 4 essential criteria related to a compelling urge to move the legs with an accompanying unpleasant sensation in the legs that is worse in the evening and at rest and improved by movement. Treatment of RLS incorporates both pharmacologic and nonpharmacologic approaches. Dopamine agonists are the mainstay of RLS treatment, but other therapies, including gabapentin, benzodiazepines, and low-potency opioids, are also commonly employed.

A clinical primer on restless legs syndrome: what we know, and what we don't know

To the Editor: Oaklander’s report1 of a patient with complex regional pain syndrome (CRPS) in addition to a movement disorder is an excellent example of the value of videotape publications. The patient is described as having progressive right lower extremity dystonia and tremor in the contralateral foot. That the movements began abruptly after vein stripping is stated as evidence that neither psychological factors nor disuse could have caused the movements, hence their organic nature as part of CRPS. Psychogenic movement disorders can be difficult to diagnose and neurologists and other physicians are often reluctant to make the diagnosis despite well-established criteria.2-4 In contrast to Oaklander’s claim, the abrupt onset of a movement disorder is a clue about a psychogenic etiology, as is adult-onset dystonia beginning in the lower extremity. Another clue is the presence of more than one movement disorder. Furthermore, there is controversy about the organic etiology of posttraumatic movement disorders, such as following vein stripping. The videotape provides additional evidence: the patient exhibits a fixed dystonic posture of the right foot (another feature suggestive of psychogenic dystonia) with an atypical low amplitude, high frequency tremor of the involved foot (not typical of dystonic tremor) and an equally atypical “bouncy” whole-leg tremor of the contralateral lower extremity. The historical and physical features of this patient support a psychogenic movement disorder. This report should not be used as evidence that movement disorders are an accepted part of the complex regional pain syndrome.

Progression of dystonia in complex regional pain syndrome [1] (multiple letters)

Impulse control disorders and dopaminergic drugs.

Prospective study evaluating IncobotulinumtoxinA for cervical dystonia or blepharospasm: Interim results from the first 145 subjects with cervical dystonia

Kapil D. Sethi

Papers

Creutzfeldt-Jakob's disease presenting with ataxia and a movement disorder

A clinical primer on restless legs syndrome: what we know, and what we don't know

Progression of dystonia in complex regional pain syndrome [1] (multiple letters)

Impulse control disorders and dopaminergic drugs.

Prospective study evaluating IncobotulinumtoxinA for cervical dystonia or blepharospasm: Interim results from the first 145 subjects with cervical dystonia