Deciphering Involuntary Movements: A Case of Seronegative Autoimmune Encephalitis With a Kaleidoscopic Presentation

Seronegative autoimmune encephalitis (SAE) can have a myriad of presenting symptoms including difficult-to-decipher involuntary movements. A 22-year-old man without significant medical history presented with seizure-like activity, altered consciousness, and numerous extraneous movements. His electroencephalogram (EEG) was difficult to interpret due to excessive myogenic artifact. The patient was intubated due to retained secretions and inability to protect the airway. He was paralyzed, and EEG showed no epileptic activity. He was treated with immunosuppression for SAE after infectious etiologies were ruled out. He clinically improved and was at his cognitive baseline at the last clinic follow-up. SAE is a rare entity requiring extensive workup and careful exclusion of other etiologies prior to diagnosis. The prognosis varies but can be improved with prompt immunosuppression and appropriate treatment of seizures if present. Involuntary movements need to be carefully evaluated to differentiate movement disorder from epileptic etiology. When titrating medications, diligence is needed so as not to overmedicate, as signified by this case.