Myasthenia Gravis Flashcards
What makes myasthenia gravis better and worse?
Worse with activity
Improves with rest
What tumour is heavily linked with myasthenia gravis?
Thymoma (thymus tumour)
In Myasthenia gravis, autoantibodies are produced against which neurotransmitter and where?
Acetylcholine at the neuromuscular junction
Myasthenia gravis symptoms mostly affect the ___ muscles and small muscles of the ___ and ___
Proximal
Head and neck
What are the symptoms of myasthenia gravis? (Any 4 but must contain first 2 on list)
Diplopia (double vision)
Ptosis
Weak facial movement
Difficulty swallowing
Fatigue in jaw
Slurred speech
Progressive weakness with repetitive movements
What 3 things can be looked at/tested in myasthenia gravis?
Thymectomy scar
Check for weakness after repetitive movement e.g get them to blink a lot
Test forced viral capacity (FVC)
What 3 antibodies are seen in myasthenia gravis?
Acetylcholine receptor antibodies
Muscle specific kinase antibodies
LRP4 antibodies
What imaging can be done to view a thymoma?
CT/MRI
What specific test can be done if there is any doubt about giving a diagnosis of myasthenia gravis?
Edrophonium test
What is the jist of the edrophonium test for myasthenia gravis?
Patient given IV dose of edrophonium chloride
Blocks breakdown of acetylcholine which provides myasthenia gravis patients with a brief improvement in symptoms
What are the treatments for myasthenia gravis? (4)
Reversible anticholinesterase inhibitors e.g pyrostigmine
Immunosuppressants e.g pred or azothioprine
Thymectomy can improve symptoms even without thymus cancer
Monoclonal antibodies e.g rituximab
What is the supportive management of myasthenic crisis? (2)
NIV e.g BiPAP
Intubation and ventilation if needed
Medical treatment of myasthenic crisis? (2)
IV immunoglobulins
Plasma exchange
