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Updated: Aug 9, 2026

Nerve Ultrasound Protocol to Detect Dysimmune Neuropathies
Published on: October 7, 2021
A case of Lewis-Sumner syndrome with conduction abnormalities only in the brachial plexus and roots
1Department of Neurology, CHA Hopital Enfant-Jesus, 1401, 18e rue Quebec City, Quebec G1J 1Z4, Canada.
Abstract:
We present a case of subacute weakness of one hand with unusual sensory involvement including the upper thorax. Despite normal distal conduction studies, a clinical diagnosis of Lewis-Sumner syndrome was made and the patient responded well to intravenous immunoglobulins. Repeated studies after clinical exacerbation finally proved the demyelinating nature of the neuropathy using proximal magnetic nerve stimulation. This case underlies the importance of seeking proximal conduction blocks in patients with suspected demyelinating neuropathy.
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