Neuro 3 pt1

Question 1

Most common disorder of Neuromuscular transmission
Cardinal features are weakness and fatigability of the skeletal muscles
Weakness increases with activity and improves c rest

Answer 1

Myasthenia Gravis

Question 2

Myasthenia Gravis

Peak incidence is what age range in males/females/

Answer 2

Peak incidence women in 20s/30s and men in 50s/60s

Question 3

hyperthyroidism
hypokalemic periodic paralysis(HPP)
RA
Sjogren’s syndrome
SLE
DM
these are all associated disorders with:

Answer 3

Myasthenia Gravis

Question 4

Acetylcholine Receptors are either __ or __

Answer 4

nicotinic or muscarinic

Question 5

The fundamental defect of Myasthenia Gravis is:

Answer 5

decrease in available acetylcholine receptors

Question 6

“Myasthenic fatigue” is caused by

Answer 6

inefficiency of NM transmission causing increasing weakness c activity

Question 7

– if you do the same thing over and over you will be less and less able to function. this term is called ____; what is this associated with?

Answer 7

Presynaptic rundown

associated with Myasthenia Gravis

Question 8

What is MuSK? What does it stand for?

Answer 8

Muscle Specific tyrosine Kinase (MuSK) is protein involved in AChR clustering at NM junction mostly bulbar
Reduces the amt. of AChRs
IgG and T-cell mediated

Question 9

Cranial nerve exercise: what's the principle eye function of each of these CN?
Abducens 
Oculomotor 
Facial 
Oculomotor

Answer 9

Abducens: LATERAL eye movement
Oculomotor: MEDIAL eye movement
Facial: Lower the eyelid
Oculomotor: Raise the eyelid

Question 10

What two nerves are involved with swallowing?

Answer 10

Vagus & Glossopharyngeal

Question 11

Face muscles are tired and you can’t smile correctly. This is called:

Answer 11

Myasthenic “snarl” of Myasthenia Gravis

Question 12

MG weakness:
~85% have ______ weakness.
How are their DTR’s? Why?

Answer 12

proximal limb weakness
DTRs preserved. Reflexes are fine because it doesn’t involve the spine’s reflex arc. –use this to differentiate between MG and some other disorders.

Question 13

weakness restricted to extraocular muscles for >3yrs

Pupillary function is still good

Answer 13

Ocular MG

Question 14

How do you dx Ocular Myathenia Gravis?

Answer 14

ice test (your eye will work better with the cool temperature), tensilon test; same as generalized MG PLUS: you have a thymoma

Question 15

What is the most common symptom of Ocular MG?

Answer 15

ptosis (whether it is uni or bilateral)

Question 16

MG testing (it’s highly sensitive & specific)

Answer 16

Acetylcholine receptor antibodies

Question 17

He showed us a video of a dog that could barely walk, but then after they did some test it could. What was the dog’s conditinon and test?
What did it do?

Answer 17

Tensilon Test in a dog with MG

Tensilon test- IV edrophonium inhibits acetylcholinesterase and transiently reverses ptosis & EOM weakness(relatively contraindicated in CAD or bronchiole asthma), need antidote atropine ready

Question 18

Tx of Myasthenia Gravis (2 types)

Answer 18

Thymectomy if there’s a thymoma
or
Aceytlchoinesterase, and then try prednisoneW

Question 19

What does ALS stand for? (what is each initial’s definition)?

Answer 19

Amyotrophy: muscle atrophy
Lateral(and anterior): white matter corticospinal tracts
Sclerosis: resultant firm gliosis – scarring and damage seen on MRI.

Question 20

Is ALS UMN, LMN, or both?

Answer 20

BOTH

Question 21

ALS- cause unknown, other than gene mutation identical in both inherited and sporadic forms.
Name 2 things that increase risk in these genetically susceptible pts

Answer 21

smoking

lead exposure

Question 22

Most common presentation of ALS

Answer 22

asymmetric distal limb weakness (80%)

Question 23

what is a bulbar symptom?

Answer 23

sx relating to the medulla oblongata

Question 24

What is the most common ALS bulbar sx? (2)

Answer 24

Dysarthria or dysphagia

Question 25

ALS: Tx

Answer 25

riluzole is first and only drug approved by FDA for slowing progression

overall tx is supportive