Clinical features, treatments, and outcomes of patients with anti-N-methyl-D-aspartate encephalitis-a single-center, retrospective analysis in China.

Objective: To describe the clinical features, laboratory data, treatment, and outcomes of anti-N-methyl-D-aspartate (NMDAR) encephalitis in Chinese patients. Methods: This retrospective study included hospitalized patients definitively diagnosed with anti-NMDAR encephalitis and positive for anti-NMDAR antibodies in the cerebrospinal fluid (CSF) in Shenzhen People's hospital, between November 2015 and February 2020. The clinical manifestation, laboratory data, treatments and outcomes were collected retrospectively. Patients were followed up for more than 1 year. Results: The study included 31 patients (15 men, 48.4%) with a median age of 31 years (interquartile range 21-48). The most common clinical presentations were psychosis (n = 23, 74.2%), seizures (n = 20, 64.5%), and memory impairment (n = 20, 64.5%). Total magnetic resonance imaging abnormalities were found in 11 patients (35.5%), with the medial temporal and frontal lobes as the most commonly involved. Abnormal electroencephalogram was observed in 16 patients (51.6%). Five out of 31 patients (19.5%) were diagnosed as neoplasm, including five females with ovarian teratoma and one male with a central nervous system tumor. Multiple immune antibodies, including anti-SSA antibody in four patients (15.4%), anti-Ro52 antibody in four (15.4%), antinuclear antibody (ANT) in four (15.4%), anti-thyroglobulin antibodies (TGAb) in five (17.2%), and thyroid peroxidase antibodies (TPOAb) in three (10.3%) were present. All patients received first-line immunization therapy (intravenous immunoglobulin, glucocorticoids, or plasmapheresis alone or combined), and only two patients (7.3%) received second-line immunization therapy (rituximab). Mechanical ventilation was more necessary in women (37.5%) than in men (6.7%) (p = 0.04), and 29 (93.5%) had favorable clinical outcomes. At more than 12 months of follow-up, the median modified Rankin Scale score decreased from 4 to 0. Conclusions: Patients with anti-NMDAR encephalitis in China had high rates of psychosis and seizures, with low rates of underlying neoplasms. A higher proportion of female patients required mechanical ventilation. Complications with other positive autoimmune antibodies were a common clinical symptoms of anti-NMDAR encephalitis. Majority of the patients obtained satisfactory outcomes in combination with early first-line and long-term immunization therapy.