Parkinson's disease Flashcards
(33 cards)
Signs of Parkinson’s disease on general inspection
Asymmetrical resting tremor: 5Hz - exacerbated by counting backwards
Hypomimia (reduced facial expression)
Extrapyramidal posture
Signs of Parkinson’s disease in the arms
Bradykinesia
Tone: cogwheel rigidity, may be enhanced by performing an action with the other limb
Normal power and reflexes
Coordination: abnormal if MSA
Signs of Parkinson’s disease in the eyes
Nystagmus: MSA
Vertical gaze palsy: PSP
Saccades: slow initiation and movement
Definition of cogwheel rigidity
Tremor superimposed on increased tone
Gait signs in Parkinson’s disease
Slow initiation
Shuffling (preceded by reduced stride length)
Hurrying = festination
Absent arm swing
Extra signs in Parkinson’s`
Glabellar tap (Myerson’s sign)
Write sentence and draw spiral (micrographia)
BP lying and standing
Completion of Parkinson’s exam
MMSE
Drug chart review
Abdominal examination: hepatomegaly + signs of CLD (DDx hepatic encephalopathy)
Causes of Parkinsonism
Idiopathic PD Parkinson Plus Syndromes: Progressive Supranuclear Palsy (PSP) Multiple system atrophy (MSA) Lewy-body dementia Corticobasilar degeneration Multiple infarcts in the substantial nigra Wilson's disease Drugs: neuroleptics, metoclopramide
Specific history for Parkinsonism
Symptoms: tremor, rigidity, akinesia Autonomic: postural hypotension, urinary problems, constipation, hypersalivation ADLs: Handwriting, buttons, shoelaces Getting in and out of a car Sleep: Turning in bed, insomnia, daytime sleepiness Complications: Depression Drug SEs esp. motor fluctuation Cause: Sudden onset? Eye or balance problems Visual hallucinations, reduced memory DHx FHx
Investigations for Parkinsonism
Bloods: caerulopasmin (low in Wilson’s)
Imaging: CT/MRI to exclude vascular cause
DaTscan: ioflupane I123 injection binds to domapinergic neurones and allows visualisation of substantial nigra - can exclude other causes of tremor e.g. benign essential tremor.
General management of Parkinsonism
MDT
Assess disability e.g. using UPDRS (Unified Parkinson’s Disease Rating Scale)
Physiotherapy: postural exercises
Depression screen
Specific medical treatment of Parkinson’s
Choice of treatment depends on balance between improvement in motor symptoms and motor and psychiatric side-effects.
MAO-B: selegiline, rasagiline.
Oral/transdermal dopamine agonist: ropinirole, pramipexol.
Levodopa (most effective symptomatic drug)
For more advanced disease:
Apomorphine SC as a rescue agent for severe ‘off’ episodes.
Amantadine or an antimuscarinic e.g. procyclidine.
COMT inhibitors e.g. tolcapone.
Use of levodopa in Parkinson’s
Given with a peripheral dopa-decarboxylase inhibitor. Preparations e.g. Sinemet. Use lowest effective dose. Long term use may cause weight loss. Side effects (N+V) are rare.
Use of dopamine agonists in Parkinson’s
Effective in controlling motor symptoms, used early in disease. Fewer motor side-effects and weaker effect cf long-term levodopa, therefore used more in younger patients. All eventually require levodopa.
Adjunct medications in Parkinson’s
Domperidone: nausea
Quetiapine: psychosis
Citalopram: depression
Epidemiology of idiopathic Parkinson’s disease
Mean onset 65 yoa
2% prevalence
Pathophysiology of Parkinson’s disease
Destruction of dopaminergic neurones in pars compact and substantial nigra
Beta amyloid plaques
Neurofibrillary tangles: hyperphosphorylated tau
Features of Parkinson’s disease
Asymmetric onset: side of onset remains worst
TRAPPS PD
Tremor (increased by stress, reduced by sleep)
Rigidity (lead pipe, cog-wheel)
Akinesia (slow initiation, difficulty with repetitive movement, micrographia, monotonous voice, mask-like face)
Postural instability (stooped gait, festination)
Postural hypotension (plus other autonomic dysfunction)
Sleep disorders (insomnia, excessive daytime sleepiness, obstructive sleep apnoea, RBD)
Psychosis esp visual hallucinations
Depression / Dementia / Drug SEs
Sleep disorder in Parkinson’s Disease
Affects ~90% of PD patients
Insomnia + frequent waking leads to excessive daytime sleepiness (EDS)
Due to: inability to turn, restless legs, early morning dystonia (drugs wearing off), nocturne, obstructive sleep apnoea
REM Behavioural sleep Disorder (RBD): loss of muscle atone during REM sleep, violent enactment of dreams
Dopamine side effects: insomnia, drowsiness, EDS
Autonomic dysfunction in Parkinson’s disease
Combined effects of drugs and neurodegeneration
Postural hypotension
Constipation
Hypersalivation (dribbling d/t reduced ability to swallow saliva)
Urgency, frequency, nocturne
Erectile dysfunction
Hyperhidrosis
L-DOPA side-effects
DOPAMINE Dyskinesia On-off phenomena = motor fluctuations Psychosis Autonomic BP problems (orthostatic hypotension) Mouth dryness Insomnia N/V Excessive daytime sleepiness
Motor fluctuations with levodopa treatment
End-of-dose (wearing off): progressively decreased benefit
On-off effect: unpredictable fluctuations in motor performance unrelated to timing of dose
Pathology of multi system atrophy
Papp-Lantos Bodies: alpha-synuclein inclusions in glial cells
Features of multi system atrophy
Autonomic dysfunction: postural hypotension
Parkinsonism
Cerebellar ataxia
