Anti-N-methyl-D-aspartate receptor encephalitis in Taiwan--a comparison between children and adults.

BACKGROUND: Since the discovery of antibodies against the N-methyl-D-aspartate receptor in 2007, anti-N-methyl-D-aspartate receptor encephalitis is increasingly recognized worldwide. We compare the clinical features of adults and children with this disorder in Taiwan. METHODS: Patients admitted to Chang Gung Memorial Hospital and Chang Gung Children's Hospital and those who were referred from other institutions because of unknown encephalitis from 2009 to 2013 were enrolled, and their clinical features were analyzed. Data on cases from a review of the literature were also included in the analysis. RESULTS: Twelve patients (10 females) aged between 7 years and 28 years with anti-N-methyl-D-aspartate receptor encephalitis were identified. Six patients (50%) were <18 years old, one of whom was male and three of whom had an underlying tumor. Overall, 91.6% of the patients presented with mood, behavioral, or personality changes; 91.6% developed seizures; 100% had stereotyped movements; 83.3% had autonomic instability; and 66.7% had hypoventilation. Responses to immunotherapy were slow and variable. Overall, 63.6% of the patients had a substantial recovery after immunotherapy or removal of the tumor, and one patient experienced neurological relapses. There were no significant differences in clinical manifestations between children and adults. CONCLUSIONS: Anti-N-methyl-D-aspartate receptor encephalitis is increasingly recognized in Taiwan. It is characterized by its clinical features, predominantly affects females with and/or without an ovarian tumor, and it is a potentially treatable disorder. It is important for neurologists to be familiar with the clinical presentations of the disease in children and young adults.