Morvan Fibrillary Chorea Associated with Monoclonal B Cell Lymphocytosis.

BACKGROUND Morvan fibrillary chorea (Morvan syndrome) is a rare disorder marked by a collection of neurological symptoms such as myokymia, peripheral nerve excitability, neuromyotonia, autonomic instability, memory impairment, and delirium. Morvan syndrome is suspected to occur through antibodies directed against voltage gated potassium channels (VGKC), and has been linked with several autoimmune conditions and hematologic malignancies. We present a case of Morvan syndrome in association with monoclonal B cell lymphocytosis.