Movement Disorders — Clinical Case

DCE Long Case

Patient brief (provided to trainee)

Patient: Mr Robert Hayes, 73 years old, retired electrician. [1]

Presenting complaint: Worsening mobility, involuntary movements, hallucinations and falls, reviewed in the movement disorders clinic. [1]

Past history:

• Idiopathic Parkinson's disease, diagnosed age 62 (11 years ago), initially tremor-dominant right hand with excellent levodopa response; motor fluctuations emerged at age 68
• Hypertension, on ramipril
• Appendicectomy aged 25
• No prior psychiatric history; no cognitive impairment documented until 12 months ago
• Independent in activities of daily living until 12 months ago; now requires assistance with dressing and showering [1]

Current medications:

• Levodopa/carbidopa 100/25, six times daily (600 mg levodopa total)
• Entacapone 200 mg with each levodopa dose
• Ropinirole prolonged-release 8 mg once daily
• Rasagiline 1 mg once daily
• Ramipril 5 mg once daily [1]

Examination findings (trainee elicits):

• Conscious, alert, cooperative; masked facies, reduced blink rate (8 per minute)
• Asymmetric rest tremor of the right hand (4 to 5 Hz, pill-rolling); mild choreiform dyskinesia of trunk and arms (peak-dose, observed 60 minutes after a levodopa dose in clinic)
• Cogwheel rigidity at right wrist and elbow greater than left
• Bradykinesia with decrement on repetitive finger tapping, worse on right
• Vertical eye movements full; no cerebellar ataxia; reflexes normal; plantars downgoing
• Gait: reduced arm swing right, shortened stride, en bloc turning with freezing on the turn (three small steps, feet appear stuck)
• Pull test: retropulsion, two steps to recover
• Blood pressure 142/78 lying, 118/66 standing (orthostatic drop of 24 systolic)
• Montreal Cognitive Assessment 24/30 (deficits in attention, executive function and visuospatial domains)
• Speech: hypophonic but intelligible [1]

Investigations:

• Full blood count, electrolytes, renal function, liver function, thyroid function — all normal
• Vitamin B12 280 pmol/L (normal), folate normal
• MRI brain (performed 2 years ago for reassessment): mild age-related atrophy, no focal lesion; no evidence of vascular parkinsonism or structural lesion
• DAT-SPECT (performed 6 years ago at diagnosis): asymmetric reduced tracer uptake in the putamen, left greater than right, consistent with presynaptic dopaminergic terminal loss [1]

Candidate's long-case presentation (SASPOP)

"Mr Robert Hayes is a 73-year-old retired electrician presenting with an 11-year history of idiopathic Parkinson's disease, now complicated by motor fluctuations, dyskinesia, visual hallucinations and falls, with emerging cognitive decline. [1]

His past history includes hypertension on ramipril. He has no prior psychiatric history. He was independent until 12 months ago. [1]

His main problems are:

1. Wearing off — each levodopa dose lasts only 2 hours, with disabling off periods
2. Peak-dose dyskinesia — choreiform movements 1 hour after each dose, reported as more disabling than the off periods
3. Visual hallucinations — formed, detailed, people and animals, with retained insight, worse in the evenings
4. Freezing of gait with falls — three falls in the last month, on turning
5. Orthostatic hypotension — 24 mmHg systolic drop on standing, contributing to falls
6. Cognitive decline — MoCA 24/30, frontal-executive pattern, with emerging PD mild cognitive impairment
7. Polypharmacy — four dopaminergic agents from three classes, increasing neuropsychiatric risk [1]

My integrated management plan addresses each problem. For the wearing off and dyskinesia, I will restructure his dopaminergic therapy around the dominant complaint of dyskinesia — reducing the size of each levodopa dose and increasing the frequency to smooth the plasma profile, adding amantadine for its antidyskinetic effect, and weaning the ropinirole slowly both to reduce dyskinesia and to address the hallucinations. For the hallucinations, I will first exclude delirium and reversible contributors, then wean the dopamine agonist, then add a cholinesterase inhibitor — rivastigmine — for both the cognitive and psychotic features, reserving low-dose quetiapine or pimavanserin if an antipsychotic is genuinely required, while explicitly avoiding haloperidol and risperidone. For the freezing of gait and falls, I will institute physiotherapy with cueing strategies, an occupational therapy home assessment, address the orthostatic hypotension by reducing the ramipril and reviewing the dopaminergic load, screen and treat vitamin D deficiency, and consider a walking aid. For the cognitive decline, I will establish serial MoCA monitoring, refer for neuropsychological assessment, treat any depression, and initiate advance care planning. I will involve the multidisciplinary team — PD nurse specialist, physiotherapy, occupational therapy, speech pathology for swallow and voice, dietetics, and social work." [1]

Examiner discussion questions and model answers

Q1: "Take me through the levodopa dose restructuring you propose." [1]

"I would reduce the size of each individual levodopa/carbidopa dose and increase the frequency. Currently he takes 100/25 six times daily, which is 600 mg total in six doses. I would change to 75/18.75 mg — that is three-quarters of a tablet — every 2 hours during waking hours, giving approximately seven to eight doses and a similar total daily levodopa of 525 to 600 mg. This lowers the peak plasma concentration after each dose, reducing the peak-dose dyskinesia, while maintaining total daily dopaminergic stimulation to reduce the off-time. I would do this in collaboration with the patient's PD nurse specialist and ask the patient to keep a motor diary for the two weeks before and after the change, recording on-time, off-time, dyskinesia and any adverse effects, so we can titrate further. In parallel, I would add amantadine 100 mg once daily in the morning — the only oral agent with good evidence for reducing levodopa-induced dyskinesia — and titrate to 100 mg twice daily if tolerated. I would monitor amantadine for confusion and hallucinations, which would be a particular concern in this patient with existing cognitive change, and which may limit its use. I would also begin weaning the ropinirole — reducing by 2 mg every one to two weeks — to transfer the dopaminergic load to levodopa, reduce the dyskinesia, and reduce the hallucination burden. If, after four to six weeks of this oral optimisation, the dyskinesia and off-time remain disabling, I would escalate to device-aided therapy — levodopa-carbidopa intestinal gel, apomorphine infusion, or deep brain stimulation — following a formal multidisciplinary assessment." [1]

Q2: "How would you investigate his orthostatic hypotension, and what would you do about it?" [1]

"Orthostatic hypotension in advanced Parkinson's disease has several contributors: autonomic failure as part of the underlying disease (alpha-synuclein deposition in the autonomic ganglia and intermediolateral cell column of the spinal cord), the dopaminergic medications — levodopa, dopamine agonists and MAO-B inhibitors all lower blood pressure — and the concomitant antihypertensives. In this patient the 24 mmHg systolic drop with standing is significant and is almost certainly contributing to his falls, particularly given his freezing of gait and cognitive impairment which further reduce his ability to compensate. My approach: first, exclude other causes — I would check a full blood count for anaemia, check electrolytes and renal function, check for sepsis and dehydration, and consider a 12-lead ECG and echocardiogram if there is any suggestion of cardiac dysfunction. Second, I would reduce or stop exacerbating medications — I would stop the ramipril, accepting a higher blood pressure target given that cerebral perfusion is the priority in a patient with neurodegenerative gait and cognition; I would reduce and stop the ropinirole as I have already proposed; I would minimise the levodopa to the lowest effective dose. Third, I would institute non-pharmacological measures — advise the patient to rise slowly from bed and chair, to sit on the edge of the bed for several minutes before standing, to drink 1.5 to 2 litres of water daily, to wear waist-high compression stockings, to eat frequent small meals to reduce post-prandial splanchnic pooling, and to avoid hot baths and large alcohol intake. Fourth, if non-pharmacological measures are insufficient, I would add a mineralocorticoid — fludrocortisone 0.1 mg daily, titrated — or an alpha-1 agonist — midodrine 2.5 to 10 mg three times daily — with monitoring for supine hypertension and peripheral oedema. Droxidopa is an alternative alpha-agonist available in some regions. I would counsel the patient that supine hypertension is the trade-off of treatment and advise him to sleep with the head of the bed elevated." [1]

Q3: "His DAT-SPECT showed asymmetric reduced uptake. What does that tell you and what does it not tell you?" [1]

"DAT-SPECT with ioflupane visualises the presynaptic dopamine transporter in the striatum. In this patient, the asymmetric reduced uptake in the putamen — left greater than right — confirms degeneration of the nigrostriatal dopaminergic terminal, which is consistent with Parkinson's disease. However, the important limitation is what DAT-SPECT does NOT tell you. It does not distinguish idiopathic PD from the atypical parkinsonian syndromes — MSA, PSP, CBD and DLB all show reduced DAT uptake because they all involve presynaptic dopaminergic terminal loss. So DAT-SPECT cannot be used to differentiate PD from these atypical syndromes. What it DOES distinguish is PD from conditions where the presynaptic terminal is intact — essential tremor, drug-induced parkinsonism, vascular parkinsonism, and psychogenic parkinsonism — where DAT-SPECT is normal. In this patient, the DAT-SPECT was performed six years ago at diagnosis to confirm a presynaptic dopaminergic lesion in the setting of an atypical early presentation, and is now redundant — the clinical picture over 11 years of typical asymmetric PD with motor fluctuations, dyskinesia and excellent initial levodopa response confirms the diagnosis. I would not repeat it." [1]

Q4: "He asks about his prognosis. What do you tell him and his wife?" [1]

"I would have this conversation honestly and with compassion, with both Mr Hayes and his wife present, and I would frame it in terms of what we know and what we can do. I would explain that Parkinson's disease is a chronic, progressive neurodegenerative condition, that he is now 11 years into the disease, and that the pattern of motor fluctuations, dyskinesia, hallucinations and cognitive change is characteristic of the advanced stage. I would be clear that the disease trajectory is now shifting from a predominantly motor disorder — which responds well to dopaminergic therapy — to a multisystem disease with cognitive, psychiatric and gait features that are less responsive to medication. I would set realistic expectations: we can improve his motor fluctuations and dyskinesia with the medication restructuring and possibly device-aided therapy, we can manage his hallucinations, we can reduce his falls risk, and we can support his cognition and his family — but we cannot halt or reverse the underlying neurodegeneration. I would discuss that the hallucinations and cognitive change are predictors of the development of PD dementia, which is the major determinant of long-term independence and institutionalisation. I would introduce the concept of advance care planning — appointing a substitute decision-maker, discussing goals around future hospitalisation, feeding in advanced dysphagia (PEG placement does not improve outcomes in PD and increases aspiration risk), and the role of palliative care input for end-stage disease. I would offer the Parkinson's support organisation — Parkinson's Australia — for information and peer support. I would not catastrophise, but I would not falsely reassure. The aim is a shared understanding that allows the patient and family to plan." [1]

Q5: "What is the role of palliative care in advanced Parkinson's disease?" [1]

"Palliative care has an expanding role in advanced Parkinson's disease and is no longer reserved solely for the terminal phase. The indications are: end-stage disease with recurrent aspiration pneumonia, significant weight loss and cachexia, end-stage dementia, refractory pain, or uncontrolled neuropsychiatric symptoms. The principles are: symptom-focused care (pain, constipation, drooling, dyspnoea, anxiety, depression), advance care planning and goals-of-care discussions, support for the family and carers (who carry an enormous burden), and a planned approach to the terminal phase. In the terminal phase of PD, the typical problems are loss of the ability to swallow oral medications (requiring transdermal rotigotine or subcutaneous apomorphine to maintain dignity and comfort without worsening confusion), aspiration pneumonia, sepsis, and cachexia. The palliative care approach allows a dignified death with appropriate symptom control, supports the family through bereavement, and avoids inappropriate escalations of care such as PEG feeding or ICU admission that do not improve outcomes. I would refer early rather than late, because the palliative care team's relationship with the patient and family needs time to develop, and because the goals-of-care conversation is often more productive when it is not under acute crisis pressure." [1]

DCE Short Case — Parkinsonian Examination

Examination instruction

Examiner: "This 68-year-old man has a tremor. Please examine his neurological system." [1]

Key signs this patient demonstrates

• Stooped, flexed posture; masked facies; reduced blink rate
• Asymmetric rest tremor, right hand, pill-rolling, 4 to 5 Hz
• Cogwheel rigidity, right wrist and elbow greater than left, with activation
• Bradykinesia with decrement on repetitive finger tapping, worse on right
• Reduced facial expression, micrographia, hypophonia
• Full vertical eye movements (excluding PSP)
• No cerebellar ataxia, no pyramidal signs, no cortical sensory loss (excluding MSA-C, CBD)
• Gait: reduced arm swing right, shortened stride, en bloc turning
• Pull test: mild retropulsion [1]

Presentation template

"I examined this 68-year-old man's neurological system. The key findings are of an asymmetric bradykinetic-rigid syndrome. There is an asymmetric rest tremor of the right hand with a pill-rolling quality, cogwheel rigidity at the right wrist and elbow greater than the left, bradykinesia with decrement on repetitive finger tapping on the right, reduced facial expression and blink rate, hypophonia, and a flexed gait with reduced arm swing on the right and en bloc turning. Vertical eye movements are full, there is no cerebellar ataxia, no pyramidal signs, no cortical sensory loss, and cognition appears intact on bedside testing. The pull test shows mild impairment of postural stability. These findings are consistent with clinically established idiopathic Parkinson's disease, asymmetric, tremor-dominant subtype. I would confirm the diagnosis using the MDS clinical diagnostic criteria, take a full non-motor history including olfaction, sleep, mood and autonomic function, and review the medication history and functional impact." [1]

Discussion

Q: "How does the asymmetric rest tremor with full vertical gaze and preserved cognition help you localise the diagnosis?" [1]

"The asymmetry strongly favours idiopathic Parkinson's disease over the atypical parkinsonisms, which are typically symmetric or only mildly asymmetric at onset. The full vertical eye movements exclude progressive supranuclear palsy, where vertical supranuclear gaze palsy — particularly downward gaze — is the hallmark and emerges early. The preserved cognition and absence of hallucinations or fluctuations exclude dementia with Lewy bodies at this stage. The absence of cerebellar ataxia and pyramidal signs excludes MSA-C. The pattern is therefore of clinically established idiopathic Parkinson's disease, tremor-dominant subtype, which carries a more favourable long-term motor prognosis and a lower risk of early dementia than the postural instability and gait difficulty subtype." [1]

Q: "What would you test to discriminate essential tremor from PD at the bedside?" [1]

"The single most discriminating feature is the relationship of the tremor to activity. Essential tremor is a postural and action tremor — present with the arms outstretched and on goal-directed movement such as pouring or finger-nose testing — and is absent at rest. Parkinson's disease tremor is a rest tremor that is present when the limb is supported and at rest, and attenuates with action. In essential tremor there is no bradykinesia, no rigidity, no postural instability, and no non-motor features. Essential tremor often improves with alcohol — a useful historical clue. A family history of tremor is common in essential tremor. If the distinction remains uncertain clinically — for example in a patient with a long-standing postural tremor who develops mild parkinsonian signs — DAT-SPECT is the investigation that resolves it: abnormal in PD, normal in essential tremor." [1]

Q: "What are the absolute exclusion criteria in the MDS clinical diagnostic criteria for PD?" [1]

"The 2015 MDS criteria (Postuma, PMID 26474316) list absolute exclusion criteria that, if present, rule out a diagnosis of PD regardless of other features. These include: cerebellar abnormalities (ataxia, gaze-evoked nystagmus) suggesting MSA-C; downward vertical gaze palsy suggesting PSP; a diagnosis of frontotemporal dementia or primary progressive aphasia; lower body-only parkinsonism suggesting vascular parkinsonism; treatment with a dopamine-blocking drug at symptom onset suggesting drug-induced parkinsonism; absence of any response to high-dose levodopa, suggesting an atypical or secondary parkinsonism; cortical sensory loss suggesting CBD; and normal dopaminergic imaging, excluding a presynaptic dopaminergic lesion. These exclusion criteria operate alongside the supportive criteria — clear levodopa benefit, levodopa-induced dyskinesia, asymmetric rest tremor, olfactory loss, cardiac sympathetic denervation on MIBG — and the red flags, which include rapid gait impairment, early bulbar dysfunction, early severe autonomic failure, falls within the first three years, anterocollis, contractures, absence of non-motor features, pyramidal signs, and bilateral ptomyoclonus." [1]