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My, what asthenia you have
Michael S Lee1, Gregory S Kosmorsky, James R Cook
1Department of Ophthalmology, University of Minnesota, Minneapolis, Minnesota, USA.
Survey of Ophthalmology
|October 22, 2008
Summary
Oculopharyngeal muscular dystrophy was diagnosed in a woman with ptosis, diplopia, and dysphagia, despite a family history of myasthenia gravis and a thymoma. Genetic testing confirmed the rare muscular dystrophy diagnosis.
Area of Science:
- Neurology
- Genetics
- Ophthalmology
Background:
- Oculopharyngeal muscular dystrophy (OPMD) is a rare, late-onset autosomal dominant genetic disorder.
- It is characterized by progressive ptosis, dysphagia, and proximal limb weakness.
Observation:
- A 59-year-old woman presented with chronic, intermittent ptosis, diplopia, dysphagia, and proximal muscle weakness.
- She had a significant family history suggestive of myasthenia gravis.
- Imaging and surgical exploration revealed a thymoma, a tumor of the thymus gland.
Findings:
- Despite the clinical presentation and family history, standard diagnostic tests for myasthenia gravis, including electromyography and antibody testing, were negative.
- Genetic testing definitively confirmed the diagnosis of oculopharyngeal muscular dystrophy.
Implications:
- This case highlights the importance of considering genetic diagnoses like OPMD even in the presence of potential confounding factors such as thymoma or family history of autoimmune conditions.
- Accurate genetic diagnosis is crucial for appropriate patient management and counseling, distinguishing OPMD from other neuromuscular disorders.
- Further research into the genetic underpinnings and therapeutic strategies for OPMD is warranted.
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