Parkinson's

Question 1

Parkinson’s disease (PD) triad

Answer 1

Resting tremor
Hypertonia (cogwheel rigidity)
Bradykinesia (festinant gait)

Question 2

PD presentation

Answer 2

Mean onset 60yrs
Tends to start with one side e.g. tremor in one hand or foot
Triad + autonomic dysfunction, sleep disturbance, reduced sense of smell
Gait is shuffling, stooped, 1 arm not swinging
Expressionless face

Question 3

PD diagnosis

Answer 3

Clinical diagnosis: bradykinesia with resting tremor and/or hypertonia
Clinical response to dopamine is supportive
DaT scan (dopamine scan, may help)
Test bradykinesia with repetitive movements, tremor should be resting and not procedural
Lewy bodies in substantia nigra, and SN degeneration initially

Question 4

PD differentials

Answer 4

Wilson’s (KF rings would be present, test caeruloplasmin + Cu)
Essential tremor (would be procedural, not resting and rest of triad not present)
Drug induced parkinsonism

Question 5

Parkinsonism plus syndromes

Answer 5

Progressive supranuclear palsy (vertical gaze palsy + PD)
Multiple system atrophy (PD + early autonomic + pyramidal features)
Cortico-basal degeneration (akinetic rigidity involving 1 limb, alien-limb phenomenon)

Question 6

PD management

Answer 6

Levodopa ±
DDC inhibitors (that doesn't cross BBB): Carbidopa, benserazide ±
COMT inhibitor: entacapone, tolcapone
Levodopa effectiveness wears off as disease progresses

D2 antagonist e.g. domperidone with levodopa for nausea
MAO-B inhibitor e.g. selegiline for very mild PD
Amantidine reduces dyskinesia from levodopa
Ropinirole/apomorphine (dopamine agonists) sometimes used for moderate disease w no cognitive impariment, risk taking SEs
Anti-ACh (benzhexol) for younger pts with autonomic issues

DBS implant for STN effective for pt responding to levodopa