ALS

Question 1

What is ALS?

Answer 1

degeneration and scarring of motor neurons in ventro-lateral aspect of SC, BS, and cortex

Question 2

There is secondary degeneration to ______________ tracts in ALS.

Answer 2

pyramidal

Question 3

What are the two potential onsets for ALS?

Answer 3

limb onset
bulbar onset

Question 4

What is cause of ALS?

Answer 4

unknown

some cases are considered familial

Question 5

What are risk factors for ALS?

Answer 5

age between 40-70
male gender
family hx
disease causing mutations

Question 6

What is the pathology of ALS?

Answer 6

massive loss of anterior horn cells in SC and CN nuclei in lower BS

degeneration of betz cells in motor cortex

astrocytic gliosis with axonal loss in CST

muscle fibers undergo denervation changes and scarring occurs

Question 7

Where does the greatest destruction occur (motor neurons)?

Answer 7

lumbar
cervical
internal capsule

Question 8

In what lamina does ALS begin in?

Answer 8

IX (9)

Question 9

How does ALS initially present?

Answer 9

both sides distally, but asymmetrical

Question 10

What neurotransmitter may play a role in contributing to ALS?

Answer 10

glutamate

Question 11

Why is it thought that glutamate may be a contributing factor in ALS?

Answer 11

people with ALS lack an enzyme that naturally breaks down excess glutamate

Question 12

Is there a genetic component of ALS?

Answer 12

yes, there appears to be an inherited autosomal trait

Question 13

What are the earliest clinical signs?

Answer 13

fasciculations (tongue)
muscle cramps
fatigue
weakness
NO sensory changes

Question 14

What is the main clinical sign?

Answer 14

chronic progressive weakness

Question 15

Why do flexors tend to be the first to develop weakness?

Answer 15

There is more real estate in central horn donated to flexors

Question 16

What cranial nerves are affected in a bulbar onset?

Answer 16

trigeminal V
facial VII
glossopharyngeal IX
vagus X

Question 17

What CN are often spared in ALS?

Answer 17

eye movement - 3,4,6

because they come off BS higher

Question 18

What tracts are often spared in ALS?

Answer 18

sensory systems and spinocerebellar tracts

Question 19

What are symptoms of bulbar onset?

Answer 19

dysphagia- swallowing
dysarthria- speaking
difficulty coughing
emotional lability
excessive drooling

Question 20

Why is respiratory dysfunction associated with ALS?

Answer 20

progressive weakness causes decreased vital capacity

ends up being the cause of death

Question 21

Is there a definitive test for ALS? How is it diagnosed?

Answer 21

No

elevated creatine phosphokinase
EMG and nerve conduction velocity
muscle and nerve biopsies
neuro-imaging

Question 22

What are diagnoses to rule out instead of ALS?

Answer 22

cervical or lumbar spondylosis
syringomyelia
MS

Question 23

What are symptoms that would exclude ALS from a differential?

Answer 23

oculomotor dysfunction
synergy present
sensory changes
autonomic dysfunction
early cognitive changes

Question 24

What is the only FDA approved drug for ALS?

Answer 24

riluzole

slows disease progression

Question 25

How long is typical course of ALS?

Answer 25

death in 3-5 years sometimes up to 10

Question 26

What may indicate a slower disease progression?

Answer 26

younger age of onset
limb onset
good quality of life
good support system