A case of Adult-onset Acute Flaccid Myelitis Accompanied by Rhombencephalitis which First Presented with Prominent Psychiatric Symptoms and Dysautonomia Mimicking Anti-N-methyl-d-aspartate Receptor Encephalitis.

A 44-year-old woman with a subacute onset of an altered mental status, urinary retention, and fluctuating blood pressure was initially diagnosed with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis, meeting the criteria of Graus et al. Cardiac arrest occurred, which required pacemaker placement. She subsequently showed profound flaccid limb paralysis, with magnetic resonance imaging demonstrating focal necrotic lesions localized in the anterior horn of the longitudinal segments of the spinal cord and in the pontine tegmentum. Enteroviruses or autoimmune encephalitis-associated autoantibodies were not detected. We herein report a case of acute flaccid myelitis with profound psychiatric symptoms and dysautonomia, resembling NMDAR encephalitis.