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Whole-body tremulousness: isolated generalized polymyoclonus
Andrew McKeon1, Sean J Pittock, Graham A Glass
1Department of Neurology, Gonda 8 South, Mayo Clinic, 200 First St SW, Rochester, MN 55902, USA. mckeon.andrew@mayo.edu
Archives of Neurology
|September 12, 2007
Summary
Generalized polymyoclonus can mimic tremor and requires accurate diagnosis. This study highlights its potential links to autoimmunity and drug side effects, emphasizing the need for proper identification.
Area of Science:
- Neurology
- Neurophysiology
Background:
- Acquired generalized repetitive myoclonus is often misdiagnosed as tremor.
- Accurate differentiation of myoclonus is crucial for effective treatment and understanding its cause.
Purpose of the Study:
- To characterize isolated generalized polymyoclonus.
- To report the diagnostic outcomes for patients presenting with this condition.
Main Methods:
- Reviewed medical records of 19 adults with generalized repetitive myoclonus.
- Utilized surface electromyography to confirm myoclonus (burst duration <50 milliseconds).
- Evaluated clinical presentations, screened for cancer and autoimmunity, and reviewed medication history.
Main Results:
- 19 patients presented with generalized polymyoclonus mimicking whole-body tremor.
- Common onset was subacute, with a mean age of 55 years.
- Diagnoses included metastatic breast cancer (2 patients) and autoimmune conditions (3 patients); 7 patients were on medications that can trigger myoclonus.
Conclusions:
- Isolated generalized polymyoclonus should be suspected in patients with whole-body tremulousness.
- Surface electromyography is key for diagnosis.
- Differential diagnosis must include autoimmune and drug-induced causes.
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