Parkinson Disease and Mimics

Question 1

Besides medication and DBS, how else can we symptomatically treat PD?

Answer 1

Exercise!

Question 2

What treatments are used for different stages of PD?

Answer 2

Early stage:

• Sinemet
• Dopamine receptor agonist (Pramiprexole)
• COMT inhibitor (Entacapone)

Later stage:
-MAO-B inhibitor (Selegiline, Rasagiline) –> MAO-B primarily metabolizes dopamine, as opposed to MAO-A which metabolizes NE and 5-HT

Late stage:

• Amantidine –> “quiets down” dyskinesias; unclear MOA
• Anti-cholinergics??
• DBS??

Question 3

Pramiprexole - MOA and potential side effects

Answer 3

Dopamine receptor agonist

Compulsive behavior, hypersexuality, sleep attacks

Question 4

Indications for DBS?

What does it do/not do?

Answer 4

• Previous good response to L-DOPA
• Current symptoms limiting patient
• Currently failing optimal medical therapy

Does: improve motor symptoms
Does NOT: slow disease progression, improve non-motor symptoms (speech, autonomic symptoms), help PD mimics

Question 5

Pathophysiology of essential tremor?

Answer 5

UNCLEAR–no “classical” findings on autopsies but seems to be inherited in AD fashion.

Question 6

Treatments for essential tremor?

Answer 6

Medications usually works best for hand tremors–don’t work for head/voice tremor. In 50% medications won’t work.

Medications:
Propanolol
Primidone and Topiramate (anti-seizure medications)

Surgery:
DBS for VIM (ventral intermediate nucleus), the relay point for signals from cerebellum to rest of brain

Question 7

Lewy Body Dementia

Answer 7

Parkinsonism + EARLY dementia + hallucinations

Dementia classically precedes parkinsonism or starts within one year.

Treatment usually focuses on psychosis > motor symptom control–classic PD therapies can worsen condition

Question 8

Multiple System Atrophy

Answer 8

Parkinsonism and/or ataxia + PROFOUND EARLY dysautonomia

Mean age of onset 60 yo

Glial cytoplasmic inclusions (alpha-synuclein) and “hot cross bun” sign on brainstem MRI

Treat dysautonomia

Question 9

Progressive Supranuclear Palsy (PSP)

Answer 9

Parkinsonism + early predominant gait instability/fall + limitations in vertical gaze + frontal cognitive signs

Tau protein and tufted astrocytes in glia
Neuronal loss with gliosis, significant atrophy of SN/brainstem
“Hummingbird” sign on MRI from midbrain atrophy

Question 10

Corticobasal Degeneration (CBD)

Answer 10

Parkinsonism + profound asymmetry + “weird stuff”
“Weird stuff” includes limb apraxia, alien limb, etc.

Characteristic astrocytic plaques and dense glial threads.