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Recessive CLCN1 mutation presenting as Thomsen disease.
Judy Thomas1, Jack Tarleton2, Steven K Baker1
1Department of Medicine, Physical Medicine & Neurology, Neuromuscular Disease Clinic, Rm 2H22, McMaster University Medical Centre, McMaster University, Hamilton, Ontario, L8N 3Z5, Canada.
Muscle & Nerve
|September 26, 2008
Summary
This case report details a young man diagnosed with Thomsen myotonia, a condition causing muscle stiffness. Genetic testing confirmed a Becker mutation, providing insights into this neuromuscular disorder.
Area of Science:
- Neurology
- Genetics
- Electromyography
Background:
- A young man presented with hand stiffness and numbness, prompting an electrodiagnostic evaluation.
- Family history revealed similar symptoms in his mother, suggesting a potential genetic link.
Observation:
- Needle electromyography showed diffuse myotonic discharges, indicative of myotonia.
- Symptoms in both the patient and his mother pointed towards Thomsen myotonia.
Findings:
- Investigations confirmed Thomsen myotonia in the patient and his mother.
- A heterozygous Becker mutation was identified in both individuals, explaining the condition.
Implications:
- This case highlights the importance of electrodiagnostic evaluation in diagnosing myotonia.
- Identifying the specific genetic mutation aids in understanding and potentially managing Thomsen myotonia.
- The findings contribute to the knowledge base of Becker mutations and their association with myotonic disorders.
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