Overview
Myasthenia gravis is an autoimmune disorder affecting neuromuscular transmission and causing fluctuating skeletal muscle weakness.
Ocular muscles, bulbar muscles, and limb muscles may be affected to varying degrees.
Weakness that worsens with use and improves with rest is a key clinical clue.
Clinical Features
Common manifestations include ptosis, diplopia, dysarthria, dysphagia, facial weakness, and fluctuating limb weakness.
Respiratory muscle involvement may produce myasthenic crisis and requires urgent assessment.
Investigation
Investigation may include antibody testing, electrophysiological studies, and imaging of the thymus when appropriate.
The diagnosis is based on the clinical pattern together with supportive laboratory and neurophysiological findings.
Management
Treatment may include symptomatic therapy, immunomodulatory treatment, and management of associated thymic disease when appropriate.
Acute respiratory deterioration requires urgent supportive management and specialist assessment.
Respiratory failure in myasthenia gravis is a medical emergency and may occur even when limb weakness appears relatively modest.
Clinical Pearls
Think of myasthenia gravis when weakness is fluctuating, fatigable, and particularly prominent in ocular or bulbar muscles.
END OF REVIEW
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