Abstract
Seronegative autoimmune encephalitis is an infrequent entity in older patients, and its presentation as rapidly progressive parkinsonism is rarely seen in cases of autoimmune encephalitis. We present a case report of an older patient who presented with worsening Parkinson's-like symptoms over a month. We highlight the importance of considering autoimmune encephalitis as a potential cause of rapidly progressive parkinsonism and the importance of radiological findings when the entire autoimmune panel is negative in such patients.