OBJECTIVETo evaluate the efficacy and safety of cyclophosphamide as a second-line drug in the treatment of children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis.

METHODSSix children with anti-NMDAR encephalitis, who showed poor response to steroids and intravenous immunoglobulin, were given cyclophosphamide as a second-line immunotherapy. Follow-up was performed to evaluate the efficacy and safety of cyclophosphamide.

RESULTSAfter first-line immunotherapy for 1-4 weeks, the six patients had reduced psychiatric symptoms, seizures, and involuntary movements; three patients had an improved level of consciousness and were able to make simple conversations. However, all the patients still showed slow response, as well as cortical dysfunction symptoms such as aphasia, alexia, agraphia, acalculia, apraxia, and movement disorders. The six patients continued to receive cyclophosphamide as a sequential therapy. They were able to answer simple questions 7 days after treatment. Three school-aged patients were able to make simple calculation, had greatly improved reading and writing ability, and almost recovered self-care ability 2-3 weeks later. The cognitive function of the six patients was almost restored to the level before the onset of disease, and their living ability returned to normal 2-3 months later. During the treatment period, there were no adverse reactions or abnormal results of routine blood test and liver and kidney function tests.

CONCLUSIONSChildren with anti-NMDAR encephalitis should be given appropriate immunotherapy as soon as possible. Cyclophosphamide as a sequential therapy has good efficacy and safety.