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Dropped head presentation of mitochondrial myopathy
Fazal Rahim1, Devanshi Gupta, Tulio E Bertorini
1From the Department of Neurology, University of Tennessee Health Science Center Memphis.
Journal of Clinical Neuromuscular Disease
|December 17, 2008
Summary
Dropped head syndrome, often caused by neck extensor weakness, can be an early sign of mitochondrial myopathy. This rare presentation warrants considering mitochondrial myopathy in differential diagnoses after excluding common causes.
Area of Science:
- Neurology
- Muscle Disorders
Background:
- Dropped head syndrome results from neck extensor muscle weakness.
- It can be an infrequent initial symptom of various neuromuscular disorders.
Purpose of the Study:
- To report two cases of dropped head syndrome as the presenting manifestation of mitochondrial myopathy.
- To highlight the importance of considering mitochondrial myopathy in the differential diagnosis of dropped head.
Main Methods:
- Case study of two patients presenting with dropped head.
- Laboratory investigations including serum lactate levels.
- Muscle biopsy for histopathological examination.
Main Results:
- Both patients exhibited dropped head as their primary symptom.
- Elevated serum lactate levels were observed in both cases.
- Muscle biopsies revealed mitochondrial proliferation.
Conclusions:
- Mitochondrial myopathy should be considered in the differential diagnosis of dropped head syndrome.
- This is particularly relevant when common causes like myasthenia gravis, polymyositis, and amyotrophic lateral sclerosis are ruled out.
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