Disorders of NMJ

Question 1

Presynaptic NMJ disorders

Answer 1

Botulism

Lambert-Eaton

Question 2

Synaptic NMJ disorders

Answer 2

AChE inhibitors

Question 3

Postsynaptic NMJ disorders

Answer 3

Myasthenia Gravis

Snake Venom

Question 4

Myasthenia Gravis

Answer 4

Anti-ACh receptor Ab attack postsynaptic muscle membrane decreasing number of available receptors

Question 5

Lambert-Eaton Syndrome

Answer 5

Anti-Ca channel Ab attack presynaptic neuron membrane preventing ACh release

Question 6

Botulism

Answer 6

Botulinum toxin acts at presynaptic neuron membrane and prevent ACh release

Question 7

When to initiate mechanical ventilation

Answer 7

NIF less than -30
FVC less than 15-20
Significant hypoxemia
Patient distress
Inability to protect airway

Question 8

L/E syndrome associated with

Answer 8

Lung cancer - 2/3 have malignancy
Image them until they glow - cancer until proven otherwise
SX exaggerate in hip girdle

Question 9

MG associated with

Answer 9

Thymus cancer

SX exaggerate in ocular, upper extremities

Question 10

Reflexes in MG/LE

Answer 10

MG - normal on stretch

LE - hypoactive or absent

Question 11

Response to muscle stimulation on MG/LE

Answer 11

MG - symptoms worsen

LE - symptoms improve