Anesthetic Management and Postoperative Course of a Patient with Anti-N-Methyl-D-Aspartate Receptor Encephalitis Associated with Ovarian Teratoma

A 32-year-old woman complained of fever, hallucinations, and seizures. Based on her symptoms and the presence of an ovarian tumor, anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis was suspected. Without waiting for specific antibody test results, she underwent emergency laparoscopic salpingo-oophorectomy. The patient received general anesthesia, which was maintained with midazolam, propofol, opioids, and rocuronium. Her anesthesia recovery was uneventful, and she had tracheal extubation after surgery. Postoperatively, her symptoms deteriorated, despite first-line immunotherapy using immunoglobulin, steroids, and plasmapheresis. She required respiratory support for central hypoventilation. As second-line immunotherapy, rituximab and cyclophosphamide were administered, resulting in gradual symptom improvement. Approximately five months after onset, she was discharged in an ambulatory condition. Early tumor resection, combined with immunotherapy, is recommended for anti-NMDAR encephalitis secondary to tumors. Since there are individual differences in the clinical courses of patients with this disease, careful perioperative management is essential.