Morvan chorea and agrypnia excitata: when video-polysomnographic recording guides the diagnosis.

INTRODUCTION: Morvan chorea is an antibody-mediated limbic encephalopathy characterized by severe insomnia, mental confusion, hallucinations, enacted dreams, hyperhidrosis, and neuromyotonia. CASE DESCRIPTION: In a 78 years old man presenting with progressive insomnia apathy and depression, a video-polysomnogram documented enacted dreams mimicking daily life activity (oneiric stupor). This finding led us to perform a search for serum antibodies to voltage-gated K+ channels, which was positive. A diagnosis of Morvan chorea was done. The patient underwent plasma exchange with complete resolution of the clinical picture. CONCLUSIONS: Oneiric stupor may represent a useful precocious diagnostic marker in Morvan chorea