ALS "Lou Gehrig's Disease" (Kerr) Flashcards
Who first characterized ALS?
Jean-Martin Charcot
ALS is a(n) _______-onset, neurodegenerative disease that preferentially affects _________________.
adult; upper and lower motoneurons
What are the main characteristic symptoms of ALS?
- progressive muscle weakness
- atrophy
- spasticity
When does death occur after diagnosis of ALS?
within 3-5 years
What is the global incidence of ALS? Does it have high/low incidence/prevalence?
- 2/100,000
- high incidence
- low prevalence
What is the approximate age of onset for ALS?
~55 years of age
TRUE or FALSE: ALS leads to degeneration of the motoneuron only
FALSE: the entire motor unit (motoneuron and muscle fibers that it innervates)
What are the different motor unit types? What kind of metabolism do each of them use? Which motor neurons are each of the units associated with? Which one has the largest muscle fibers?
- slow (S) - oxidative metabolism; type I
- fast fatigue resistant (FR) - glycolytic and oxidative metabolism; type IIA
- fast fatigue (FF) - glycolytic metabolism; type IIB –> LARGEST fibers
What are some known risk factors for ALS?
- age
- gender 1.5:1 male:female
- family history - 20% familial
What are some possible risk factors for ALS?
- athleticism
- exposure to heavy metals/herbicides/chemicals
- smoking
- trauma (consistent/persistent head trauma)
- gulf war service
What is the difference between bulbar and spinal ALS? Which one is more common?
- bulbar affects swallowing and speaking
- spinal causes weakness in one distal limb; more common
TRUE or FALSE: for a diagnosis of ALS, only lower motoneurons signs must be present
FALSE: both upper and lower motoneuron
TRUE or FALSE: ALS symptoms must be present in 1 or 4 body segments to be diagnosed
FALSE: must be present in 3 of 4
What are the upper motoneuron symptoms?
- moderate weakness
- hyperreflexia
- pathological reflexes
- pseudobulbar affect
- spasticity
- loss of dexterity
- slowed movements
What are the lower motoneuron symptoms?
- severe weakness
- hyporeflexia
- muscle atrophy
- fasciculations
- muscle cramps
- muscle hypotonicity or flaccidity
10-20% of fALS cases are associated with _____________ mutations to the _________________ gene that transcribes _______________.
autosomal dominant; superoxide dismutase (SOD1); sarcoplasmic Cu/Zn SOD1