L13 Neuromuscular Transmission and NMJ Disorders

Question 1

what is myasthenia gravis?

Answer 1

IgG binds to and blocks AChR;
destroy AChR via complement sys;
acceleration of conventional removal of AChRs

Question 2

what is a major correlation of myasthenia gravis?

Answer 2

thymus hyperplasia in 70% of cases, thymoma in 10%

Question 3

symptoms of myasthenia gravis?

Answer 3

fatigability
more proximal weakness than distal
ocular weakness
bulbar weakness

Question 4

name two special tests for myasthenia gravis?

Answer 4

ACh esterase inhibitor

ice-pack on eyes

Question 5

what’s lambert-eaton syndrome?

Answer 5

IgG antibodies against the pre-synaptic voltage-gated Ca2+ channels

Question 6

what is lambert-eaton commonly associated with?

Answer 6

80% with small cell lung cancer

50% with malignancy

Question 7

symptoms of lambert-eaton?

Answer 7

post-exercise facilitation
gradual leg weakness more proximal
autonomic dysfunction (dry mouth, constipation)
minimal ocular/bulbar symptoms