27. Extrapyramidal Disease CPC Flashcards
how much dopamine production must be lost for pts to develop signs of Parkinsonism?
70-80%
what are the components of the basal ganglia?
- striatum (caudate and putamen)
- Globus Pallidus (interna and externa)
- subthalamic nuclei
- substantia nigra
what is a good site for DBS in parkinson’s disease?
subthalamic nucleus
term for: Quick (“dance-like”) movements that are rapid, jerky and irregular, usually affecting muscles of the face orobuccal cavity and limbs.
chorea
Involuntary slow writhing (“worm-like”) movements flowing from one to the next, sometimes associated with chorea
athetosis
a twisting movement, usually of the neck or trunk
dystonia
includes a throwing or flinging movement, usually of one side, where it is called a hemibalism.
ballismus
fleeting purposeless movement, however they tend to be repetitive and stereotyped, as opposed to chorea, which is random.
tics
hyperkinesia that can come in different speeds (fast versus slow) and can be exaggerated in different positions or actions.
tremor
the opposite of dyskinesia. consists of a slowing of movement. This can manifest as slowed postural corrections to being thrown off balance or decreased facial expressiveness. It can include a type of stiffness, called rigidity, which is different than spasticity since it produces smooth resistance to passive movement. can also affect initiation of movement and patients can “get stuck”.
Bradykinesia
Decreased facial expressiveness. Is a bradykinesia of facial muscles
mask facies
Increase in resting muscle tone. In parkinsonism it is consistent throughout the range of motion, unlike the “clasp-knife” effect of spasticity. When rigidity and tremor are both present “cogwheeling” results.
rigidity
what are some drugs that can cause Parkinson’s like symptoms?
levodopa, neuroleptics
a flinging movement of one side of the body that would result from a small stroke in the contralateral subthalamic nucleus.
hemibalism
most common causes of choreoathetosis?
Genetic (Huntington’s)
advanced age
cerebrovascular disease
cerebral palsy
what is the genetic pattern of Huntington’s?
autosomal dominant, with complete penetrance (50% of offspring)
what does genetic anticipation mean?
the number of CAG repeats can go from 36 to 40 in a generation and the patient may be the first person who is symptomatic
how many CAG repeats will result in Huntington/s?
40+
Clinical triad of huntington’s?
chorea, dementia, behavior change (may result in problems with the law)
what drug will make Huntington’s wlrse?
levodopa (given for Park)
what are some drug treatments for Huntington’s?
neuroleptics, which block dopamine. (haloperidol, perphenazine)
what is the problem with chronic use of neuroleptics?
they can sensitize the system, and over time can have a reverse effect –> tardive dyskinesia
what do dopamine-depleting drugs cause, and should we use them to treat Huntington’s?
cause severe depression: we shouldn’t use them.
essential tremor: does it run in families? what is the age of onset?
yes. age of onset is 25-55 yrs.
how bad can essential tremor get?
tends to get worse with time: sometimes will get so bad it’s hard to function.
does essential tremor tend to be unilateral or bilateral?
bilateral.
parkinson’s is unilateral
what is affected the most with essential tremor?
upper limbs, head, voice.
what is something that we wouldn’t necessarily recommend but that can help essential tremor?
alcohol
what anti-epilepsy drug is NOT effective for essential tremor?
valproate: has tremor as a side effect
what beta-blocker can be used for essential tremor?
propanolol
what anti-epileptic can be given for essential tremor?
gabapentin, topiramate
what can be done for refractory essential tremor?
DBS to the ventral intermediate nucleus of the thalamus
Parkinson tremor: action or static? sporadic or familial? unilateral or bilateral? progression? area of body?
- static/resting
- sporadic
- unilateral at onset
- may progress quickly
- arm, leg
essential tremor: action or static? sporadic or familial? unilateral or bilateral? progression? area of body?
- postural/action (intention)
- often familial
- bilateral
- slow progresion
- hands, head, voice
what might be non-Parkinson’s causes of parkinsonism?
neuroleptic drugs (block dopamine, used for Huntingtons)
metoclopramide
stroke in basal ganglia
Park: tremor improves or worsens with voluntary movement?
improves.
some other sx of Parkinson’s?
including decreased facial expression (masked facies) or a soft voice (hypophonia), small handwriting (micrographia), flexed posture or difficulty with swallowing (dysphagia), shuffling, or hesitancy/freezing of gait.
Parkinson’s: histological finding?
- marked depigmentation of substantia nigra
- loss of 70%+ of domaninergic neurons
- Lewy Body inclusions in the dopa neurons that remain
what is the content of Lewy Body inclusions?
spherical aggregates of synuclein folded in a beta pleated sheet configuration
what is Lewy Body disease?
Lewy Bodies scattered throughout the brain. different clinical pic from Parkinson’s
Risk factors for Parkinson’s?
age, twin with early onset, positive family history, possibly exposure to environmental toxins
Genes + Environment?
Really, we are not sure in the majority of cases
Mortality in Park patients?
mean survival 15 yrs after onset, reduced overall lifespan
which Park pts tend to do better? why is there a decline in longevity for Park pts?
do better: pts without dementia (20-20% develop dementia
shortened lifespan primarily due to complications: infections, aspirations, UTIs, PEs, falls
what is meant by Parkinson-Plus?
you can’t account for what they have on teh basis of rigidity, bradykinesia, tremor.
generally do worse since we have no effective treatemtns
what is MPTP toxicity?
accidental byproduct of illicit drug synthesis
produces Lewy Bodies, all clinical elements of PD.
what are clues that suggest Park-Plus rather than PD?
- lack of tremor
- poor response to usual treatment
- symmetry of signs
- prominent autonomic dysfunction
- early halluciontions, dementia
- frequent early falls
- myoclonus
- impaired EOM
why do we give sinemet (with carbidopa and levodopa)?
carbidopa prevents conversion of levodopa in blood before it gets into the brain, allows us to use a smaller dose of dopamine. fewer side effects
besides sinemet, what drug treatment for PD?
-dopamine agonists. (COMT inhibitors, MAO inhibitors) not as effective but allow us to use less dopamine
why might anticholinergics work in treating PD?
The effects of acetylcholine in the brain tend to be opposite of dopamine. You get similar but not as powerful benefit with these medications that often have severe systemic anticholinergic side-effects.
when do we use amantadine to treat PD?
It’s useful at suppressing the dyskinesias that people get as a side effect of too much dopamine. In Parkinson’s patients where we have caused dyskinesias by excessive dopamine, amantadine can sometimes help those dyskinesias
where has DBS placement been most effective in treating PD?
globus pallidus interna, and subthalamic nucleus
