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Updated: Jun 14, 2026
06:37
Immunolabelling Myofiber Degeneration in Muscle Biopsies
Published on: December 5, 2019
Episodic myoglobinuria in a primary gamma-sarcoglycanopathy
Loren Pena1, Katherine Kim, Joel Charrow
1Department of Human Genetics, The University of Chicago, Chicago, IL, USA.
Neuromuscular Disorders : NMD
|April 2, 2010
Summary
Episodic myoglobinuria, a rare symptom of limb-girdle muscular dystrophy (LGMD), was observed in a patient presenting with rhabdomyolysis. Muscle biopsy confirmed LGMD due to a gamma-sarcoglycan gene mutation, highlighting diagnostic importance.
Area of Science:
- Neurology
- Genetics
- Biochemistry
Background:
- Episodic myoglobinuria is a known complication of metabolic myopathies and certain muscular dystrophies like Duchenne and Becker.
- It is infrequently associated with limb-girdle muscular dystrophy (LGMD).
Observation:
- A patient presented with progressive muscle weakness, tenderness, and myoglobinuria.
- Rhabdomyolysis was noted one week after initial presentation.
Findings:
- Immunohistochemistry revealed absent gamma-sarcoglycan staining in muscle tissue.
- A homozygous mutation in the gamma-sarcoglycan gene was identified, confirming the diagnosis of LGMD.
- Myoglobinuria has only been reported twice previously in LGMD cases.
Implications:
- Myoglobinuria can be an indicator of muscular dystrophy, not solely metabolic myopathies.
- Muscle biopsy and immunohistochemistry are crucial diagnostic tools for identifying LGMD.
- This case expands the clinical presentation spectrum of limb-girdle muscular dystrophy.
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