Anti-dipeptidyl-peptidase-like protein-6 (DPPX) autoimmune encephalitis associated with severe multifocal dystonia

Anti-DPPX encephalitis is a rare form of autoimmune encephalitis characterized antibodies against a subunit of Kv4.2 potassium channels. Characteristic clinical features include cognitive dysfunction, parasomnias, psychosis, and seizures. Motor symptoms typically include myoclonus, tremor, and midline ataxia. DPPX encephalitis presenting as new-onset focal dystonia has not been previously described.