Parkinson’s Diagnosis, Presentation, Symptoms Flashcards
PD defintion
State of dopamine deficiency in the brain → functional imbalance between inhibitory dopamine and excitatory acetylcholine
Two primary pathophysiologic features of PD
- loss of dopaminergic cells in the substantial nigra and basal ganglia
- formation of Lewy bodies in the remaining substantial nigra neurons and other parts of the brain
How much nigral cell death has to happen before the disease manifests clinically?
80%
How can PD be self-propagating?
DA production and oxidation via MAO-B hydrogen peroxide → forms free radicals when it comes into contact with iron in the substantia nigra → treatment is with medications that increase dopamine!
Normal aging process involves a _____decline of DA
steady
In PD, how does DA decline?
The process is accelerated
PD diagnosis
BRADYKINESIA with at least one of the following:
limb muscle rigidity, resting tremor, postural instability
Limb muscle rigidity presentation
May manifest as a consistent “lead pipe rigidity” or “cogwheel rigidity;” movements are very slow and stiff
Usually begins unilaterally, but both sides are eventually affected
Resting tremor presentation
Tremor is present when the hand’s at rest
Usually begins unilaterally in the distal limb
“Pill-rolling” movement of fingers and thumbs
Postural instability presentation
Forward flexion of the neck and trunk → “stooped” posture
Flexion of the arms at the elbow
Individual leans forward and down
Bradykinesia presentation
Early signs may be isolated to distal muscles but eventually, all muscle groups may be affected
Facial masking: mask-like appearance or lack of expression, decrease in eye blink frequency
Motor acts become difficult (increasingly difficult with repetition)
Micrographia when it comes to handwriting something
“Freezing” → patient feels like their feet are stuck to the ground and they can’t move. Occurs in advanced PD
Exclude other causes of PD…
Drug-induced Parkinsonism: APS!
Other neurodegenerative conditions, NPH, toxins (CO poisoning, manganese, hydrogen sulfide, MPTP), neoplasms/strokes/lesions in nigrostriatal path
Clinical presentation: primary
bradykinesia, postural instability, resting tremor, rigidity
Clinical presentation: motor symptoms
decreased dexterity, dysarthria, freezing at initiation of movement, slow turning
Clinical presentation: autonomic symptoms
bladder and anal sphincter disturbances, constipation, diaphoresis, orthostatic hypotension, loss of BP control
