Motor Neuron Disease Associated with Voltage-Gated Potassium Channel Antibodies

Eric M. Thompson, Robert A. E gan

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DOI: 10.4236/nm.2011.22010                

Abstract

Introduction: Antibodies to voltage-gated potassium channels have been implicated in causing a host of peripheral and central nervous system disorders. However, the presence of these antibodies has not been previously associated with motor neuropathy. We describe the first case of acquired motor neuron disease associated with voltage-gated potas-sium channel antibodies. Case Report: The patient is an 81-year-old female who developed signs and symptoms of an idiopathic motor neuron disease. The patient was found to have increased antibodies to voltage-gated potassium chan-nels in the absence of a known metastatic or autoimmune process. Magnetic resonance imaging of the cervical spine demonstrated increased signal in the anterior horn regions of the cervical and upper thoracic spinal cord on T2-weighted imaging. The patient’s disease progression was refractory to both intravenous immunoglobulin and ster-oid therapy. Conclusion: Voltage-gated potassium channels may be causal or simply associated with motor neuron disease; this relationship needs to be elucidated. Testing for these antibodies may be warranted in cases of idiopathic rapidly progressing motor neuron disease.

Keywords

Voltage-Gated Potassium Channels, Motor Neuron Disease, Antibody, Central Nervous System Disorders

Conflicts of Interest

The authors declare no conflicts of interest.

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