To report a case of atypical neurological manifestations associated with ganglionic nicotinic acetylcholine receptor (α3-AChR) autoantibody.

The ganglionic nicotinic acetylcholine receptor autoantibody (α3-AChR Ab) typically causes subacute or insidious onset autoimmune dysautonomia. A broader neurological association has been increasingly recognized, including peripheral neuropathy, multiple sclerosis and encephalopathy. To our knowledge, this is the first case of chorea and optic neuropathy being associated with this autoantibody.

Case report and literature review.

A previously healthy 37-year-old man presented with a 14-month history of constellation of symptoms including acute onset of vertigo, nausea and vomiting followed by progressive limb weakness and diffuse paresthesia. Five months later, he developed left-sided vision loss, diffuse involuntary movements, urinary frequency, unilateral hyperhidrosis, orthostatic intolerance, bilateral tinnitus, mood swings and memory impairment. Physical examination revealed a left optic neuropathy, nystagmus, left-sided hearing loss, patchy sensory loss to all modalities, limb and trunk choreiform movements and sensory ataxia. Serum studies revealed high titer of α3-AChR Ab (0.12 nmol/L; normal <0.02 nmol/L). Striational antibody was borderline positive (titer 1:120; normal <1:120). Nerve conduction study revealed a patchy sensory neuropathy consistent with sensory ganglionopathy. He was treated with plasma exchange and valbenazine with improvement of choreiform movements.

A3-AChR Ab can present with a wide spectrum of central, peripheral and autonomic nervous system manifestations due to receptor localization. Clinical recognition is the key which leads to prompt diagnosis. Our understanding of autoimmune neurological syndromes is evolving with development and utilization of autoantibody testing, which poses a positive impact to patients’ outcome.