Parkinson's Disease Flashcards
What are the motor features of PD?
Cogwheel rigidity Bradykinesia Resting tremor- pill rolling Loss of facial expression Shuffling gait and stooped posture
What is seen in the neurons affected by Parkinson’s disease?
Lewy body formation
Where is the losos of neurons in PD?
There is loss of the dopaminergic neurons of the substantia nigra
What are some differential diagnosis for PD?
Essential Tremor Vascular Parkinsonism Drug Induced Parkinsonism Parkinson's Plus Syndromes Wilson's Disease
Compare the features of PD and essential tremor?
PD if often unilateral, ET is bilateral
PD is tremor at rest, ET is intentional
PD is associated with gait changes, rigidity, bradykinesia and cognitive disturbances and ET is not
ED improves with alcohol, PD does not
ED is associated with family history PD is not
What gait changes are seen with PD?
Lack of arm swing
Shuffling gait
Stooped posture
What is seen in vascular parkinsonism?
Typically lower body parkinsonism
Patients have the shuffling gait
Due to vascular disease- patients often have HTN
What drugs can cause parkinsonism?
Antipsychotics
Or any other dopamine antagonists
What is seen in parkinson’s plus?
Patients have parkinsonian features but also other features
- Supranuclear palsy- limitation in eye movements
- Multiple system atrophy- also have urinary incontinence, walking difficulties and parkinson’s features
What disorder of copper metabolism can cause Parkinsonism features?
Wilson’s Disease
What scan is used to look at dopamine transporter levels?
SPECT Scan- Shows dopamine uptake which will be reduced in parkinson’s
What drug is often used first to manage PD if there is little impact on QoL?
Dopamine Agonists
Ergot Derived- Bromocriptine, Cabergoline
Non ergot derived- pramipexole, ropinirole
How does L-Dopa work?
It is converted to dopamine by decarboxylase enzymes
Why are decarboxylase inhibitors often given with L-Dopa?
This is to prevent peripheral conversion of L-Dopa to dopamine. When it happens peripherally it causes nausea due to stimulation of the CTZ.
Carboxylase inhibitors include carbidopa.
Often given in combination e.g. co-careldopa
Why are COMT inhibitors also given in PD?
To prevent peripheral conversion of L-DOPA by COMT, this also happens centrally. COMT inhibitors therefore prevent this breakdown and can increase the amount of L-Dopa to be converted to dopamine.
