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Immunolabelling Myofiber Degeneration in Muscle Biopsies
Published on: December 5, 2019
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Young girl presenting with exercise-induced myoglobinuria
Balaji Krishnaiah1, Jennifer Jheesoo Lee2, Matthew Paul Wicklund1
1Department of Neurology, Penn State University, 30 Hope Drive, EC 037, Hershey, Pennsylvania, 17033, USA.
Muscle & Nerve
|June 15, 2016
Summary
Alpha sarcoglycanopathy, a muscular dystrophy, can present atypically with exercise intolerance and myoglobinuria but preserved muscle strength. Early recognition of this rare presentation is key for managing patient quality of life.
Area of Science:
- Neurology
- Genetics
- Biochemistry
Background:
- Sarcoglycanopathies are a group of autosomal recessive muscular dystrophies characterized by progressive muscle weakness.
- These conditions result from mutations in genes encoding sarcoglycan proteins, affecting muscle fiber integrity.
Observation:
- A case study details a Caucasian girl with childhood onset of exercise intolerance, myalgia, and dark urine.
- Elevated creatine kinase levels (up to 18,000) and myoglobinuria were noted.
- Muscle biopsy revealed diminished alpha-sarcoglycan staining.
Findings:
- Genetic analysis identified compound heterozygous mutations in the SGCA gene (n.C229T; p.Arg77Cys and n.C850T; p.Arg284Cys).
- These mutations are associated with alpha-sarcoglycanopathy.
- The patient exhibited preserved muscle strength into adolescence, an uncommon presentation for sarcoglycanopathies.
Implications:
- This case highlights an atypical presentation of alpha-sarcoglycanopathy, emphasizing the importance of considering exercise intolerance and myoglobinuria.
- Early diagnosis and intervention are crucial for preventing comorbidities and improving the quality of life for affected individuals.
- This underscores the need for comprehensive genetic and clinical evaluation in suspected muscular dystrophy cases.
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