Dystonia, athetosis, and epilepsia partialis continua in a patient with late-onset Rasmussen's encephalitis

Rasmussen's encephalitis is a rare autoimmune disorder characterized by intractable epilepsy and progressive hemispheric dysfunction. The disorder usually affects children, although cases have been reported with symptom onset in late adolescence or adulthood. Myoclonus is common in Rasmussen patients, usually occurring as part of epilepsia partialis continua (EPC); however, other hyperkinetic movements are rare. This report documents a 19-year-old woman with Rasmussen's encephalitis whose clinical presentation was dominated by foot dystonia, arm athetosis, and EPC. Intravenous immunoglobulin improved both hyperkinetic movements and EPC, but benefit was transient. The clinical significance and implications of these findings are discussed.