Morvan’s Syndrome, or Morvan’s fibrillary chorea (MFC), is a rare autoimmune disease named after nineteenth century French physician Augustin Marie Morvan. “La chorée fibrillaire” was first coined by Morvan in 1890 when describing patients with multiple, irregular contractions of the long muscles, cramping, weakness, pruritis, hyperhidrosis, insomnia, and delirium.  It normally presents with a slow insidious onset over months to years.  90% of cases spontaneously go into remission, while the other 10% of cases lead to death.
In one of the few reported cases, the subject presented with muscle weakness and fatigue, muscle twitching, excessive sweating and salivation, small joint pain, itching and weight loss. The subject also developed confusional episodes with spatial and temporal disorientation, visual and auditory hallucinations, complex behavior during sleep and progressive nocturnal insomnia associated with diurnal drowsiness. There was also severe constipation, urinary incontinence, and excessive lacrimation. When left alone, the subject would slowly lapse into a stuporous state with dreamlike episodes characterized by complex and quasi-purposeful gestures and movements (enacted dreams). Marked hyperhidrosis and excessive salivation were evident. Neurological examination disclosed diffuse muscle twitching and spontaneous and reflex myoclonus, slight muscle atrophy in the limbs, absence of tendon reflexes in the lower limbs and diffuse erythema especially on the trunk with scratching lesions of the skin
In most of the reported cases, the treatment options were very similar. Plasmapheresis alone or in combination with steroids, sometimes also with thymectomy and azathioprine, have been the most frequently used therapeutic approach in treating Morvan’s Syndrome. However, this does not always work, as failed response to steroids and to subsequently added plasmapheresis have been reported. Intravenous immunoglobulin was effective in one case.  In one case, the dramatic response to high-dose oral prednisolone together with pulse methylprednisolone with almost complete disappearance of the symptoms within a short period should induce consideration of corticosteroids.  In another case, the subject was treated with haloperidol (6 mg/day) with some improvement in the psychomotor agitation and hallucinations, but even high doses of carbamazepine given to the subject failed to improve the spontaneous muscle activity. Plasma Exchange (PE) was initiated, and after the third such session, the itching, sweating, mental disturbances, and complex nocturnal behavior improved and these symptoms completely disappeared after the sixth session, with improvement in insomnia and reduced muscle twitching. However, one month after the sixth PE session, there was a progressive worsening of insomnia and diurnal drowsiness, which promptly disappeared after another two PE sessions.  In another case, the subject was treated with prednisolone (1mg/kg body weight) with carbamazepine, propanolol, and andamitriptyline. After two weeks, improvement with decreased stiffness and spontaneous muscle activity and improved sleep was observed. After another 7-10 days, the abnormal sleep behavior disappeared completely.  In another case, symptomatic improvement with plasmapherisis, thymectomy, and chronic immunosupression provide further support for an autoimmune or paraneoplastic basis.  Although thymectomy is believed to be a key element in the proposed treatment, there is a reported case of Morvan’s Syndrome presenting itself post-thymectomy