J Clin Neurol.  2014 Jan;10(1):69-71.

Myasthenia in Acquired Neuromyotonia

• Byun JI
• Moon HJ
• Hong YH

Abstract

BACKGROUND
Acquired neuromyotonia (NMT) forms part of the spectrum of acquired peripheral nerve hyperexcitability syndrome, and is thought to be caused by antibodies to voltage-gated potassium channels (VGKC). Exertional weakness is unusual unless autoimmune myasthenia gravis (MG) is superimposed.
CASE REPORT
A case of acquired NMT accompanied by exertional weakness without coexistence of seropositive MG is reported herein.
CONCLUSIONS
Clinical and electrophysiological observations suggest that the cholinergic overactivity in NMT can compromise the safety factor sufficiently to cause a defect in neuromuscular junction transmission.

Keyword

neuromyotonia; myasthenia; neuromuscular junction

MeSH Terms

Antibodies
Isaacs Syndrome*
Myasthenia Gravis
Neuromuscular Junction
Peripheral Nerves
Potassium Channels, Voltage-Gated
Antibodies
Potassium Channels, Voltage-Gated

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