To analyze the efficacy and safety of plasma exchange in the treatment of anti-NMDA receptor encephalitis.

Introduction: To investigate the clinical efficacy and safety of plasma exchange (PE) in the treatment of glucocorticoid-insensitive patients with serum anti-N-methyl-d-aspartate (anti-NMDA) receptor antibody-negative and serum anti-NMDA receptor antibody-positive encephalitis.

Methods: The clinical data of 20 patients with anti-NMDA receptor antibody encephalitis treated between January 2015 and December 2022 were collected. The general information, clinical symptoms, auxiliary examination, treatment (hormone, PE, etc.), adverse reactions, clinical efficacy, and other related data were retrospectively compared and analyzed.

Results: A total of 8 cases had adverse reactions (9.76%, 8/82), including 4 cases (4.88%, 4/82) of allergy and 2 cases (2.44%,2/82) of thrombocytopenia. In patients with anti-NMDA receptor antibody encephalitis who were not sensitive to glucocorticoids, the effective rate of PE was 80.0% (p = 0.0005).

Conclusion: PE combined with glucocorticoid is more effective than glucocorticoid alone in the treatment of anti-NMDA receptor antibody encephalitis patients with positive or negative anti-NMDA receptor antibodies. Most adverse reactions were mild and easy to manage. It does not cause obvious blood cell loss. PE is a safe and acceptable treatment. However, our study has limitations, and due to the small number of people and the fact that plasmapheresis was performed after glucocorticoid therapy, further prospective clinical studies are warranted.