myasthenia gravis

Myasthenia Gravis

Objectives

To be familiar with presentation of MG
To appreciate the potential danger of MG
To recognize the types of crises in MG
To know about prevention of crises
To know about the initial management of crises in MG.
To know about inpatient follow up.

Mechanism

Autoimmune disease directed against the neuromuscular junction.

Etiology: idiopathic.

Clinical picture
Chronic relapsing-remitting
Affects young females mostly
Potentially life threatening
Fatigable muscle weakness
Variable
Asymmetric
Cranial nn initially affected

Video

Diagnosis

Bed side test: Simpson’s, Tensilon’s
TFT, Connective tissue screen
CT scan chest
Anti-bodies
Repetitive nerve stimulation: decremental
Single fiber EMG


Crises: Diagnosis
Myasthenic: more common

Cholinergic: rare

- Clinical: sweating, salivation, bronchial secretions, miosis, bradycardia
- Tensilon test

Crises: initial Mangement

Myasthenic: RCU, Intubation, IVIg, Plasmapharesis

Cholinergic: RCU, Intubation

Crises: Prevention
Immunomodulation
IVIg
Plasmapharesis

Treatment

Anti-cholineasterases (Pyridostigmin)
Preventing crises
Immunological therapy
-Steroids\steroid sparing agents
-Thymectomy
- Immunosuppressant's


Inpatient follow up
Counting up to 20
Forced Vital Capacity: 30mL/kg
Check for cholinergic hyperstimulation
Check for side effects of IVIg, Plasmapharesis
Check for side effects of steroids
Treat infection aggressively
Prevent Veno-Thromboembolic phenomena