Neurodegenerative disorders Flashcards
What are some general features of neurodegenerative disorders?
CNS degeneration, abnormal prtein accumulation. Patterns of neuronal loss, functional impact.
How are the cerebellum, motor neurons, and cortex affected in neurodegenerative conditions?
Cerebellum: ataxia
Motor neurons: weakness (e.g ALS)
Cortex: memory, language, insight/planning
What is dementia?
Impaired memory and cognition along with personality changes; decreased overall fxnality. Maintain consciousness, common feature of neurodegeneration.
What is the MC cause of demntia?
Alzheimer disease (AD). Strongly associated with age
What acummulats in the brain with AD?
Beta-amyloid proteins (plaques)
What do B-amyloid palques cause in the brain?
Neurotoxic, decreased neurotransmission, cortical atrophy. Breakdown = tau proteins (tangles).
What do tau proteins indicate?
Breakdown of neurons. General neurodegeneration.
How does AD progress?
Insidious/progressive: altered mood/behavior decreased cognition, disorientation, amnesia
What is seen within 5-10 years with AD?
Aphasia, immobility. Lethal infx: pneumonia (MC)
What is seen within 5-10 years with AD?
Aphasia, immobility. Lethal infx: pneumonia (MC)
Is there a genetic component to AD?
10% genetic. Linked with down syndrome bc of chromosome 21
What is parkinsonism?
Abormal motor fxn., tremor, rigidity, bradykinesia, instability
What is the MC cause of parkinsonism?
Parkinson disease (But not always)
What is damaged in parkinson disease?
Damage to dopaminergic neuron. Altered CNS synaptic transmission. Substantia nigra **, cortex, medulla, pons.
What kind of inclusions are associated with Parkinson’s disease?
Alpha-synuclein = Lewy body (round/oval, dense core, pale halo).
What age group is MC affected by Parkinson’s?
Onset: Age 45-65
What kind of discoloration is noted with Parkinson’s?
Pallor of the substantia nigra
How progressive is Parkinsons?
Immobility 10-15 years
What are some physical features of Parkinson’s?
“Cogwheel” rigidity & festinating (shuffling) gait
“Pill-rolling” of thumb & index fingers
Exressionless (poker/mask face)
What are some behavior disorders in advanced stages of PD?
Dementia, hallucinations (cortex) within 1 year of motor symptoms (Lewy body dementia).
Possible autonomic dysfunction
What are some conditions associated with death in PD?
Frequent falls, infection (pneumonia).
What is the Tx for Parkinson’s?
L-DOPA (increased dopamine), deep brain stim.
Manages movement dysfunction, does not slow progression, becomes less effective
What is Huntington disease?
Progressive neurodegeneration. Severe cerebral atrophy. Prominent at caudate and putamen nuclei
What are the genetic implications of HD?
Autosomal dominant, Huntington gene. Trinucleotide repeat: CAG (anticipation).
What are the inclusions associated with HD?
Ubiquinated Huntington protein
What is the onset for HD?
Delayed onset: 30-40 years
What are the features of HD?
Chorea (jerky, dance-like) of entire body.
Altered congnition: severe dementia, insanity
MC lethal within 15 years.
What is associated with death in HD?
Pneumonia
Injuries
Choking
Suicide
What is ALS?
Denervation atrophy of motor neurons. Unique combination of LMN and UMN death.
What are the areas of LMN and UMN that are killed with ALS?
LMN: Cord, brainstem. Corticospinal and corticobulbar tracts. Anerior horn cells, ventral nerve roots.
UMN: Betz cells (posterior frontal lobe)
What is the onset of ALS?
Insidious: asymmetric distal extremity weakness. MC among males, age: 40-50 years.
What kind of atrophy is noted with ALS?
Progressive muscle atrophy and decreased strength. Fasciculation: involuntary muscle contractions
What are the features of ALS?
Weakness, hyperreflexia (bc of betz cells), spasticity. Preserves sensation and extraocular motor fxn. Difficulty speaking, swallowing, breathing
What is the onset like of ALS?
Rapid progression (Stephen Hawking: atypical)
What causes death with ALS?
Respiratory paralysis (pneumonia)
What causes ALS?
90% sporadic. 10% are familial, autosomal dominant (earlier onset) - associated with superoxide dismutase abnormalities.
What causes ALS?
90% sporadic. 10% are familial, autosomal dominant (earlier onset) - associated with superoxide dismutase abnormalities.
