Multicenter and Prospective Clinical Registry Study of Anti-N-methyl-D-aspartate Receptor Encephalitis in China

Inclusion Criteria: 1. Older than 6 months. 2. Encephalopathy symptoms (change of mental state and consciousness level) persist for more than 24 hours; 3. At least one or more clinical features of the followings: fever, epilepsy, focal neurological deficiency symptoms, changes in CSF(cerebrospinal fluid inflammatory), changes in EEG (electroencephalogram), radiographic abnormalities; 4. Clinical suspected encephalitis, but conventional detected methods cannot make etiology clear. 5. Signed informed consent Exclusion Criteria: 1. Infants less than 6 months; 2. The metabolic encephalopathy; 3. Infectious encephalitis with clear pathogen clinically, referring the specific pathogenic microorganisms, including: bacteria, virus, fungus, parasite, spirochete and so on; 4. Non-infectious encephalitis with clear diagnosis clinically, including: multiple sclerosis, neuromyelitis optic, acute disseminated encephalomyelitis and so on.