Polymyoclonus, laryngospasm, and cerebellar ataxia associated with adenocarcinoma and multiple neural cation channel autoantibodies.
OBJECTIVE
To describe and provide audiovisual documentation of a syndrome of polymyoclonus, laryngospasm, and cerebellar ataxia associated with adenocarcinoma and multiple neural cation channel autoantibodies.


METHODS
Case report with video.


METHODS
University hospitals. Patient A 69-year-old woman presented with subacute onset of whole-body tremulousness and laryngospasm attributed to gastroesophageal reflux.


RESULTS
Further evaluation revealed polymyoclonus, cerebellar ataxia, and laryngospasm suspicious of an underlying malignant neoplasm. Surface electromyography of multiple limb muscles confirmed the presence of polymyoclonus. The patient was seropositive for P/Q-type voltage-gated calcium channel antibody; subsequently, whole-body fluorine 18 fluorodeoxyglucose positron emission tomography and cervical lymph node biopsy revealed widespread metastatic adenocarcinoma. Follow-up serologic evaluation revealed calcium channel antibodies (P/Q type and N type) and potassium channel antibody.


CONCLUSIONS
We highlight the importance of recognizing polymyoclonus. To our knowledge, this is also the first description of a syndrome of polymyoclonus, laryngospasm, and ataxia associated with adenocarcinoma and these cation channel antibodies.
Lim
Shen-Yang
SY
University of Malaya, Kuala Lumpur, Malaysia.
Mason
Warren P
WP
Young
Nathan P
NP
Chen
Robert
R
Bower
James H
JH
McKeon
Andrew
A
Pittock
Sean J
SJ
Lang
Anthony E
AE
D000230:Adenocarcinoma / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D000368:Aged; D001323:Autoantibodies / Q000276:immunology*; D001932:Brain Neoplasms / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D020865:Calcium Channels, P-Type / Q000276:immunology; D020907:Calcium Channels, Q-Type / Q000276:immunology; D002524:Cerebellar Ataxia / Q000150:complications*; D004576:Electromyography; D005121:Extremities / Q000294:innervation / Q000502:physiology; D005260:Female; D005764:Gastroesophageal Reflux / Q000150:complications; D006801:Humans; D007116:Immunization, Passive; D007473:Ion Channels / Q000276:immunology*; D007826:Laryngismus / Q000150:complications*; D018482:Muscle, Skeletal / Q000502:physiology; D009207:Myoclonus / Q000150:complications*; D049268:Positron-Emission Tomography; D015221:Potassium Channels / Q000276:immunology; D014057:Tomography, X-Ray Computed
D001323:Autoantibodies; D020865:Calcium Channels, P-Type; D020907:Calcium Channels, Q-Type; D007473:Ion Channels; D015221:Potassium Channels