We have been treating an 8-year-old girl with anti-NMDAR encephalitis for more than 1 year. The disease manifested with movement disorder mimicking polyradiculomyelitis.
During the first week of hospital admission, the girl received intravenous immunoglobulin with no clinical response. Within 3 weeks, she developed deep coma with autonomic instability.
Her serum and CSF were positive for anti-NMDAR antibodies. Plasma exchange and high-dose corticosteroids were immediately applied, followed by rituximab, with no effect.
Therefore, cyclophosphamide treatment was started of which she received seven cycles. Three cycles stabilised her autonomic system, but she developed intractable motor restlessness and remained in coma.
Four subsequent cycles were strengthened by removal of antibodies from peripheral blood with immunoadsorptions; nevertheless, the girl's neurological status remained unchanged.