Movement disorders Flashcards
triad of parkinsonism?
‘RAT’
- rigidity (cogwheel)
- akinesia
- tremor
what is akinesia
can be in the form of slowness of movement (bradykinesia) or difficulty initiating movement with small amplitude of movements (hypokinesia)
describe the tremor in parkinsonism
4-6Hz resting tremor, pill rolling. Exacerbated by concentrating e.g. counting back from 100
what is Parkinson’s disease?
a progressive neurodegenerative disease characterised by levodopa-responsive parkinsonism
histopathology of PD?
intracytoplasmic, eosinophilic, alpha synuclein containing inclusions known as lewy bodies
lewy bodies specifically target where in the brain in PD?
the pars compacta of the substantia nigra: causes disturbance in the dopaminergic pathway
how is PD diagnosed?
clinically
PD
1) onset gradual or sudden?
2) symmetrical or asymmetrical?
3) related to age?
gradual onset
often starts asymmetrical
typically in >55s, risk increases with age
clinical features of PD?
triad of parkinsonism (RAT)
stooped posture, postural instability, slow shuffling gait
micrographia
masked facies
non-motor symptoms (constipation, REM sleep behaviour disorder, depression, dementia)
most effective treatment of PD?
levodopa
how does response to levodopa change over time
honeymoon period: initially consistent response throughout the day
progressive decline in response causing akinesia
and possibly overshoot from akinesia to dyskinesia
Levodopa
1) MOA
2) side effects
3) combined with which other drug? why?
1) dopamine precursor that can cross the BBB
2) hypotension, nausea, dyskinesia
3) peripheral dopa-decaboxylase inhibitor (carbidopa) to prevent peripheral metabolism of levodopa
Monoamine oxidase B inhibitors
1) MOA
2) side effects
3) examples?
4) used when in PD?
1) inhibit monoamine oxidase B enzyme, which catabolises dopamine to homovanillic acid
2) hypertensive crisis when consuming tyramine-containing foods e.g. cheese
3) rasagiline, selegiline
4) can be used as an add-on or even as monotherapy in early mild PD
Dopamine agonists
1) MOA
2) side effects
3) examples?
4) used when in PD?
1) directly stimulate dopamine receptors
2) hypotension, nausea, ankle swelling, hallucinations
3) pramipexole
4) can be used as initial treatment in younger pts (<70) due to high risk of dyskinesia in younger patients on levodopa
causes of drug induced parkinsonism?
chlorpramazine haloperidole lithium valproic acid metoclopramide
treatment of drug induced parkinsonism?
cessation of the agent
change from typical (1st gen) to atypical antipsychotic
symptomatic treatment with anticholinergics e.g. benztropine, procyclidine
Lewy body dementia vs parkinson’s disease dementia?
PD dementia: onset of dementia >1 year after onset of parkinsonism
LBD: onset of dementia before or at same time as parkinsonism
3 core features of lewy body dementia?
dementia
parkinsonism
visual hallucinations
features of multiple system atrophy?
parkinsonism (poor response to levodopa) autonomic dysfunction (postural hypotension, ED, urinary urgency) +/- cerebellar dysfunction
MRI of multiple system atrophy?
putaminal atrophy and ‘hot cross bun’ appearance on axial section of pons
features of progressive supranuclear palsy?
- axial akinesia and rigidity
- loss of balance and unexplained falls
- forgetfulness
- dysarthria
- loss of eye movements (supranuclear gaze palsy, esp on vertical plane)
MRI of progressive supranuclear palsy?
midbrain atrophy with a hummingbird sign on sagittal view
what causes vascular parkinsonism?
multiple small strokes or infarcts
people with vascular parkinsonism tend to have more problems with TREMOR/ GAIT and have more problems in the UPPER/ LOWER body
gait
lower
vascular parkinsonism progresses very QUICKLY/ SLOWLY compared to other types of parkinsonism and it has a GOOD/ POOR response to levodopa
slowly
poor
what kind of scan can be used to differentiate vascular dementia from other parkinsonian syndromes?
SPECT
most common psychiatric problem in PD?
depression
what is essential tremor?
postural or action tremor
essential tremor is commonly inherited as an autosomal ___ trait
dominant
essential tremor often improves after consumption of ____ and may be helped by what drug class?
alcohol beta blockers (propranolol)
name 2 cerebellar pathway tremors?
intention tremor
holmes (rubral) tremor
what causes intention tremor? most commonly seen in which disorder?
cerebellar or cerebellar pathway lesions
most commonly seen in MS
what is a holmes (rubral) tremor
triad of resting tremor, postural tremor and intention tremor
what is dystonia
involuntary muscle spasms leading to abnormal postures of the affected body part
what is the underlying cause of dystonia
co-contraction of agonist and antagonist muscles
dystonia can be focal such as in ____ or generalised
blepharospasm
treatment of dystonia?
anticholinergics
botulin toxic 1st line for focal dystonia
and/or surgery
what is chorea
continuous spontaneous jerky movements, irregularly timed and randomly distributed
what is huntington’s disease?
gradually progressive autosomal dominant neurodegenerative disorder
genetic abnormality in huntington’s disease?
CAG triplet repeat
what is ‘genetic anticipation’ in Huntington’s disease?
CAG repeat increases with each subsequent generation causing increasing severity and earlier onset of disease
early and later signs of Huntington’s disease?
early: personality changes, depression, apathy, clumsiness, dysarthria, dysphagia, abnormal eye mvoements
then progresses to chorea, rigidity and dementia
neurotransmitter changes in Huntington’s disease?
reduced GABA and ACh
increased dopamine
name a drug which can provide symptomatic relief in Huntington’s
Tetrabenazine (anti-choreic)
- works by inibits VMAT; thereby limiting dopamine vesicle packaging and release
Sydenham’s chorea
1) is one of the major manifestations of __ __
2) who does it occur in?
3) features?
4) treatment?
5) T/F: now rare in the developed worly
1) rheumatic fever
2) children, mainly girls 5-15
3) widespread chorea, behavioural disturbance and obsessive compulsive symptoms
4) self limiting, most resolve in 6 months
5) true
Sydenham’s chorea
1) is one of the major manifestations of __ __
2) who does it occur in?
3) features?
4) treatment?
5) T/F: now rare in the developed worly
1) rheumatic fever
2) children, mainly girls 5-15
3) widespread chorea, behavioural disturbance and obsessive compulsive symptoms
4) self limiting, most resolve in 6 months
5) true
what are tics
relatively brief intermittent stereotyped involuntary movements or sounds
tourette syndrome includes multiple ___ tics and one or more ___ tics, which must last longer than a ___
motor
phonic/ vocal
year
maximum age at onset for tourette syndrome?
18
Tourette syndrome
1) tics usually begin where in the body
2) simple phonic tics include…
3) complex vocal tics include…
4) about __% of individuals have psychiatric comorbidity
5) most common psychiatric comorbidity?
1) head and face. Blinking often the first tic
2) sniffing, coughing, gulping, snorting, throat clearing
3) barking, making animal noises inappropriate voice intonations, uttering strings of words
4) 90
5) ADHD, followed by OCD
treatment of Tourette syndrome?
mild disease: counselling, behavioural/ psychosocial interventions and habit reversal training
If medication indicated: risperidone best for tic control (clonidine +/- risperidone if co-existing ADHD)
what is myoclonus?
sudden brief shock-like involuntary movement caused by muscular contraction or inhibition
what can cause myoclonus?
neurodegenerative disease (Huntington's, wilson's, multiple system atrophy) severe hypoxia (lance-adams) drugs/ toxic causes
what is hemiballism? what is it caused by?
wild flinging/ throwing movements of one arm or leg, usually as a result of a cerebrovascular lesion to the subthalamic nucleus
features of restless leg syndrome?
unpleasant sensations or an urge to move in the legs (or other body parts), classically at night and only, almost instantly, relieved by getting up and walking about
can also occur when trying to relax when sitting or lying down during the day
causes of restless leg syndrome?
IDA
uraemia
pregnancy
parkinson’s
restless leg syndrome has a positive response to what drug class?
dopamine agonists (pramipexole)
What is
1) dystonia
2) chorea
4) myoclonus
5) hemiballism
1) involuntary muscle spasms leading to abnormal postures of the affected part
2) continuous jerky movements, irregularly timed and randomly distributed
3) brief shock-like involuntary movement caused by muscular contraction or inhibition. Irregular (cf clonus: regular)
4) wild flinging movements of one arm/ leg
