L5 Parkinson's disease and atypical Parkinsonism

Question 1

what is hypokinetic, hyperkinetic

Answer 1

hypo - too little movement

hyper - too much movement

Question 2

what are features of parkinsonism

Answer 2

akinesia
rigidity
tremor
postural abnormality

Question 3

what is the lifetime risk of PD

what % of cases start below 40

Answer 3

1 in 40

5%

Question 4

what are early non motor features of PD

Answer 4

olfactory loss, REM sleep behaviour disturbance

constipation

Question 5

what is the core feature of PD and what does it encompass

Answer 5

akinesia

encompasses bradykinesia (slowness of movement), poverty of movement, progressive fatiguing and decrement of repetitive movement 
difficulty with initiating movement

Question 6

what is the Hz range of a tremor

Answer 6

3-6 Hz tremor in hands

sometimes 6-10 Hz postural tremor

Question 7

what does early postural insatbility suggest

Answer 7

atypical parkinsonian condition

Question 8

what pathology is affected in PD

Answer 8

• loss of dopaminergic neurons from the substantia nigra
• accompanied by presence of Lewy bodies - intracytoplasmic eosinophilic inclusion bodies - which stain with antibody to alpha-synuclein

Question 9

what is the treatment of PD

Answer 9

• symptomatic
• medical treatment aims to increase the amount of dopaminergic transmission in the brain
• surgical treatment aims to improve the disordered messages from the diseased basal ganglia

Question 10

how is levodopa given and why?

Answer 10

given together with a peripheral dopa-decarboxylase inhibitor, enzyme so
stops the breakdown of levodopa in the periphery. helps to prevent side effects such as nausea, increases central availability

Question 11

what is levodope+benserazide =

levadopa+carbidopa =

Answer 11

=co-beneldopa (Madopar)

co-careldopa (Sinemet)

Question 12

what is a side effect of levodopa

Answer 12

long term use associated with development of dyskinesias anf fluctuations

Question 13

what are dopamine agonists give examples

Answer 13

drugs that directly stimulate dopamine receptors

bromocriptine, pergolide, cabergoline, roprinirole, pramipeoxle (oral), apomorphine (subcutaneous)

Question 14

what are side effects of dopamine agonists

Answer 14

hallucinations, nausea, faintness, sleepiness

Question 15

what are other drugs used in PD

Answer 15

MAO-B inhibitors : selegiline, rasagiline
COMT inhibitors: entacapone, opicapone
amantadine (reduces dyskinesia)
anticholinergics (sometimes used for tremors but too many side effects

Question 16

what has replaced surgical operation in pd

Answer 16

stimulation of subthalamic nucleus

Question 17

what causes drug induced parkinsonism, and what drugs were used where

Answer 17

• caused by dopamine blocking or depleting drugs
• neuroleptic drugs used in psychiatric practice and anti emetic drugs such as metoclopramide are common offenders
• effects reversible

Question 18

how is toxic parkinsonism MPTP caused and what does it do in primates

Answer 18

used by drug abusers

in primates selectively kills nigral neurons (used to create an animal model of parkinsonism but without lewy )

Question 19

what is post-encephalitic parkinsonism

Answer 19

• Von Economo’s disease
• occurred as a pandemic of post infectious parkinsonism in the 1920s
• features are hypersomnolence and psyhciatric disturbance, followed by parkinsonism
• infective agent not been identified

Question 20

what is vascular pseudo-parkinsonism

Answer 20

• blocks blood vessels
• patients with small vessel cerebrovascular disease
• lower body
• no rest tremor or upper limb akinesia
• marche a petit pas, wide-based gait, freezing
• Dementia, UMN signs, postural instability common

Question 21

what happens in progressive supranuclear palsy

Answer 21

• supranuclear vertical gaze palsy (atrophy of midbrain)
• early falls
• bulbar failure (problems with speech and swallowing in brainstem)
• axial rigidity
• pyramidal signs

Question 22

multiple system atrophy

MSA-P/MSA-C

Answer 22

parkinsonism, poorly levodopa responsive, for a cerebellar syndrome PLUS autonomic failure:
urinary incontinence
erectile dysfunction
postural hypotension (bp not maintained when standing up)
striatonigral degeneration, sporadic olivopontocerebellar atrophy, Shy-Drager syndrome

Question 23

what happens in Dementia with lewy bodies (initial symptoms)

Answer 23

symptoms - executive function, attention, visuospatial disorder
-parkinsonism, visual hallucinations, REM sleep behaviour disorder, sensitivity to neuroleptics