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Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis
Published on: March 4, 2014
Bilateral hand amyotrophy with PMP-22 gene deletion
A Gochard1, A M Guennoc, J Praline
1Department of Neurology and Clinical Neurophysiology, CHU Bretonneau, Tours, France.
European Journal of Neurology
|January 16, 2007
Summary
Hereditary neuropathy with liability to pressure palsies (HNPP) can present unusually. A PMP-22 gene deletion caused a novel HNPP phenotype in a woman with bilateral hand weakness.
Area of Science:
- Neurology
- Genetics
- Molecular Biology
Background:
- Hereditary neuropathy with liability to pressure palsies (HNPP) is a genetic disorder characterized by recurrent, focal nerve palsies.
- The PMP-22 gene is a key component in myelin sheath formation and its alterations are associated with HNPP.
- Phenotypic variability in HNPP complicates diagnosis and underscores the need for genetic confirmation.
Observation:
- A 52-year-old woman presented with bilateral hand weakness, initially mimicking a motor neuron disorder.
- Clinical examination revealed a diffuse, predominantly distal demyelinating neuropathy.
- No significant past medical history was reported.
Findings:
- Genetic analysis confirmed a deletion in the PMP-22 gene.
- The patient's clinical presentation represented a novel phenotype associated with PMP-22 gene deletion.
- This finding expands the known spectrum of HNPP presentations.
Implications:
- This case highlights the importance of considering HNPP in patients with atypical neurological presentations, even without a history of recurrent palsies.
- The identification of a novel phenotype associated with PMP-22 deletion broadens the diagnostic criteria for HNPP.
- Further research into genotype-phenotype correlations in HNPP is warranted to improve diagnostic accuracy and patient management.
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