Clinical manifestations of myasthenia gravis
- Shawn J Bird, MD
Shawn J Bird, MD
- Professor of Neurology
- University of Pennsylvania School of Medicine
- Section Editors
- Jeremy M Shefner, MD, PhD
Jeremy M Shefner, MD, PhD
- Section Editor — Neuromuscular Disease
- Professor and Chair of Neurology, Barrow Neurological Institute
- Professor of Neurology, University of Arizona, Phoenix
- Clinical Professor of Neurology, Creighton University
- Ira N Targoff, MD
Ira N Targoff, MD
- Section Editor — Muscle Disease
- Professor of Medicine, Section of Rheumatology
- University of Oklahoma Health Sciences Center
Myasthenia gravis is the most common disorder of neuromuscular transmission. It is now one of the best characterized and understood autoimmune disorders. The hallmark of the disorder is a fluctuating degree and variable combination of weakness in ocular, bulbar, limb, and respiratory muscles. Weakness is the result of an antibody-mediated, T-cell dependent immunological attack directed at proteins in the postsynaptic membrane of the neuromuscular junction (acetylcholine receptors and/or receptor-associated proteins). The diagnosis of myasthenia gravis can be established by clinical and serologic testing [1,2].
The clinical manifestations of myasthenia gravis will be reviewed here. Other aspects of this disorder are discussed separately. (See "Ocular myasthenia gravis" and "Diagnosis of myasthenia gravis" and "Differential diagnosis of myasthenia gravis" and "Pathogenesis of myasthenia gravis" and "Treatment of myasthenia gravis".)
There are two clinical forms of myasthenia gravis: ocular and generalized.
●In ocular myasthenia, the weakness is limited to the eyelids and extraocular muscles. (See "Ocular myasthenia gravis".)
●In generalized disease, the weakness commonly affects ocular muscles, but it also involves a variable combination of bulbar, limb, and respiratory muscles.
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