14) Degenerative Medicine Flashcards
Parkinson’s Disease
Neuromuscular disorder where the substantia nigra loses its ability to produce dopamine, so it leads to a disinhibition of the cholinergic system which causes tremors & rigidity (too much cholinergic activity) or akinesia & bradykinesia (too little dopamine)
What causes PD?
- Idiopathic
- Genetics
- Encephalitis
- Toxic encephalopathy
What does TRAPPED stand for?
- Tremors (Resting)
- Rigidity
- Akinesia/Bradykinesia
- Postural Instability
What is the 1st early clinical sign of PD?
Loss of trunk rotation w/gait
Most is the most common sx of PD?
Tremor
When PD tremors start, are they seen unilaterally or bilaterally?
Unilaterally
When PD rigidity starts, is it seen unilaterally or bilaterally?
Unilaterally
What is akinesia associated w/?
Fixed postures
Bradykinesia
Paucity of movement characterized by an inability to perform purposeful movements
What types of movements does akinesa/bradykinesia usually effect?
Sequential/simultanous movements
What does the postural instability & gait impairments associated w/PD cause?
Incr fall risk
What kind of gait deviations do pt’s w/PD have?
- Decr heel strike
- Loss of heel-toe progression
- Decr step length
- Loss of trunk rotation
- Retropulsion
- Festinating gait
- Shuffling gait
What are the gait deviations associated w/PD caused by?
Rigidity & Bradykinesia
What percent of PD pt’s have intellectual changes?
>50%
Why do PD pt’s get depression?
Loss of dopamine neurons & sensory deprivation
Sx’s of PD
- Resting tremors
- Rigidity
- Akinesia/Bradykinesia
- Postural instability
- Micrographia
- Whispering, montone voice
- Masked face
- Incr salvation & sebaceous secretions
What are the gold standard drugs to tx PD?
Dopaminergics
What are the side effects of dopaminergics?
- Orthostatic hypotension
- On/Off Times
- Dyskinesia
- Hallucinations
- Decr drug effectiveness over time
What do dopamine agonists do?
Make the brain think there’s more dopamine, so it delays the need for dopaminergics, but incr need for YOPD
Side Effects of Dopamine Agonists
- Drowsiness
- Edema
- Obsessive problems
What do anticholinergics do?
Restores the ACh/Dopamine balance to control early tremors
Side Effects of Anticholinergics
- Dry mouth
- Confusion
- Urinary retention
- Sedation
What do MAO-B inhibitors do?
Slows the breakdown of dopamine by decr free radical production
What are the side effects of MAO-B inhibitors?
Orthostatic hypotension & Insomnia
What do COMT inhibitors do?
Blocks the enzyme that deactivates dopamine
What do antivirals do for PD?
Helps w/rigidity & bradykinesia
- Low doses smooth fluctuations
- High doses suppress dyskinesia
Why is botox given to PD pt’s?
For hypertonia
What surgical procedure can be done to help alleviate the sx’s of PD & what is the problem w/it?
Deep Brain Stimulation–>Not always effective
- Can only return pt to their best “on time”
True or False: Deep brain stimulation can decr the amount of meds a PD pt needs to take by up to 30%.
True
What is the On/Off Phenomenon & what causes it?
Short duration therapeutic response followed by rapid decr in that response–>Occurs bc PD meds are toxic to receptor sites
Huntington’s Disease
Progressive autosomal dominant disorder characterized by movement abn’s (chorea), personality disturbances, & dementia bc of atrophy of the BG & striatum
When do sx’s of HD usually start?
40’s or 50’s
True or False: Anyone who inherits the HD gene will eventually have sx’s.
True
Explain the pathophys of HD
Neurons that project from the striatum to the substantia nigra are depleted so there’s decr GABA, ACh, & metenkephalins, which causes incr potency of dopamine & NE, which goes on to cause imbalance of excitatory & inhibitory responses between the BG & thalamus
What body parts does Huntington’s chorea effect more?
UE & face more than LE’s
When does Huntington’s chorea incr/decr?
- Incr during complex/stressful tasks
- Disappears during sleep
What other issues can arise w/HD?
- Vision changes
- Oromotor Impairments
- Sleep disturbances
- B&B dysfxn
- Neuro & psych disorders
For a pt w/HD, what will movement testing reveal?
Dysmetria & dysdiadochokinesia
Clinical Manifestations of HD
- Early chorea can look like restlessness or be integrated into normal movement strategies
- MMT can be normal in the early stages, but may be difficult bc of motor disturbances
- Hypotonia can be present initally, progressing to rigidity & bradykinesia
- Choreiform gait
Why are eye movement abn’s are common w/HD commo & why?
- Disturbed saccades
- Decr smooth pursuit
*Bc of disturbances w/ocular & extraocular muscles
What oromotor impairments are commonly seen w/HD?
- Dysarthria
- Dysphagia
- Cachexia
What is a common early sign of HD?
Neuro & psych disorders
Is there a cure for HD?
No
What meds are given for HD & why?
Anticonvulsants &/or antipsychotics–>Block dopamine transmission if chorea is interfering w/fxn
What are the side effects of HD meds?
- Acute dystonia
- Psudo-parkinsonism
- Akasthesia
- Tardive dyskinesia
Prognosis for HD
- Earlier the onset, the more severe the disease
- Death usually occurs 15-20yrs after onset
ALS
Degenerative scarring/sclerosis in the lateral regions of the spinal cord, brainstem, & cortex causing UMN & LMN sx’s
Who does ALS most commonly effect?
Males
What is the mean age of onset for ALS?
57y/o
What causes ALS?
Possibly genetics
What can be used to r/o a dx of ALS?
Presence of:
- Cognitive sx’s
- Oculomotor sx’s
- B&B sx’s
- Sensory sx’s
Explain the patho of ALS
- Demyelination & glisosis of the corticospinal & corticobulbar tracts
- Death of motor neurons in the brainstem & spinal cord cause denervation & subsequent atrophy
True or False: Before HD sx’s start, 80% of motor neurons in the affected area may already be dead.
True
What is the pattern of onset for ALS sx’s?
UE, LE, Bulbar
What are the significant features of ALS?
- Asymmetrical weakness w/muscle fiber sparing
- CN3 & B&B sparing
Outcomes of ALS
- Paralysis of all spinal musculature
- Paralysis of all muscles innervated by CN’s
- Sensory issues
- Pt’s w/bulbar onset tend to have a more rapid progression
- Occasional improvement bc of collateral sprouting
- Death occurs 4-5yrs after onset
What does the medical management of ALS consist of?
- Riluzole–>Glutamate anatagonist that slows excitotoxic cell death to extend life by 1-2yrs
- Antioxidants–>Limits further injury to motor neurons & protects against cell death
- Neurotrophic factors–>Aid in the recovery of injured but still viable motor neurons
- PROM or antispasmodics–>Muscle spams
- Adequate nutrition
- Mechanical ventilation
- End of life care
Alzheimer’s Disease
Condition of progressive dementia characterized by slow decline in memory, language, visuospatial skills, & cognition
In pt’s w/AD, what is the 1st structure to show pathological changes?
Cerebral cortex
What is the most significant finding in pt’s w/AD?
Amyloid plaque & Neurofibrillary tangles
What is the clinical presentation of AD?
- Personality changes (Indifference, Impulsivity, & Irritability)
- Loss of ability to do basic math
- Eating, sleeping, & sexual behavior disorders
- Bouts of inappropriate behavior
- Lack of spontaneity
- B&B dysfxn
- Akinesia & dystonia
- Rigidity
What are the most common sx’s of of AD?
Loss of ability to learn new info & spatial disorientation
True or False: In pt’s w/AD, there can by UMN signs, but the’yre typically related to another pathology.
True
Medical management of AD
- Anticholinesterase Therapy–>Blocks the enzyme that degrades ACh to help w/memory, language, thinking, & judgement
- NMDA Receptor Agonists–>Improves memory, attention, reasoning, & language skills
- Manipulation of the environment
PT Management of AD
- Use structured environment
- Maximize repetition & use of fxnl movement patterns
- Use procedural memory tasks
Why do AD pt’s not have declarative memory?
Bc of hippocampal damage
If a pt w/AD can’t follow directions, what should you do ID fxn limitations?
Rely on observational analysis
Dx Criteria for AD
- By exclusion
- MMSE score
- Presence of personality changes
- Normal MRI
