Parkinson's disease

Question 1

What is Parkinson’s?

Answer 1

A chronic progressive neurological disorder characterised by resting tremor, rigidity, akinesia, and postural instability.

Question 2

What is cause of Parkinson’s?

Answer 2

Selective loss of dopamingeric neurons in the substantia nigra causes loss of control of motor output.

Lewy bodies accumulate in the basal ganglia, brainstem, and cortex.

Question 3

What non-motor symptoms are seen in Parkinson’s?

Answer 3

Dementia
REM sleep disorder
Autonomic e.g. constipation, urgency, ED, salivation.

Question 4

What are differential diagnoses in Parkinson’s?

Answer 4

Essential tremor
Dementia with Lewy bodies
FT dementia
Parkinson plus disorders e.g. progressive supranuclear palsy 
Chronic use of dopamine antagonists.

Question 5

What investigations would you do in suspected Parkinson’s?

Answer 5

Thyroid function (distinguish from hyperthyroid)

Imaging: CT/MRI brain. Will be normal in Parkinson’s, but abnormal in Parkinson +, DLB.

Functional imaging: DATSPECT can show presynaptic dopaminergic function.

Question 6

What are the main types of drugs used in Parkinson’s?

Answer 6

Replace dopamine: L-dopa (with carbidopa)

Dopamine agonist: cabergoline, pramipexole, ropinrole.

MAO-B inhibitors: selegiline

COMT inhibitors: entacapone.

Question 7

What complications are seen in advanced Parkinson’s?

Answer 7

L dopa induced dyskinesia.
On/off fluctuations
Poor balance and falls