Factors Affecting the Response to First-Line Treatments in Patients with Anti-N-Methyl-D-Aspartate Receptor Encephalitis

BACKGROUND AND PURPOSE: Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most common type of autoimmune encephalitis. This study aimed to explore the possible factors affecting the response to first-line treatments in patients with anti-NMDAR encephalitis. METHODS: We enrolled 29 patients who were diagnosed as anti-NMDAR encephalitis between January 1, 2015, and June 30, 2018. They were divided into the remission and nonremission groups according to their response to first-line treatments. The demographics, clinical manifestations, main ancillary examinations, follow-up treatments, and prognosis of patients were recorded. The symptoms reported on in this study occurred before treatments or during the course of first-line treatments. RESULTS: There were 18 patients (62.07%) in the remission group and 11 patients (37.93%) in the nonremission group. Compared to the remission group, a higher proportion of the patients in the nonremission group exhibited involuntary movements, decreased consciousness, central hypoventilation, lung infection, and hypoalbuminemia. The nonremission group had a high incidence of increased intracranial pressure and significant elevations of the neutrophil-to-lymphocyte ratio in peripheral blood (NLR), aspartate aminotransferase, and fibrinogen. Six patients (54.55%) in the nonremission group received second-line immunotherapy. Only one patient (3.45%) died, which was due to multiple-organ failure. CONCLUSIONS: Anti-NMDAR-encephalitis patients with more symptoms—especially involuntary movements, disturbance of consciousness, central hypoventilation, and accompanying hypoalbuminemia and pulmonary infection—may respond poorly to first-line treatments. Positive second-line immunotherapy therefore needs to be considered. Admission to an intensive-care unit, increased cerebrospinal fluid pressure, and increased NLR might be the significant factors affecting the response to first-line treatments.