Anti-N-Methyl-D-Aspartate Receptor (NMDAR) Encephalitis Associated With Mediastinal and Ovarian Teratomas: A Case Report

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is the most common type of autoimmune encephalitis. Approximately 80% of patients with anti-NMDAR encephalitis are women. Tumors are detected in approximately 50% of female patients with anti-NMDAR encephalitis, of which 96% are ovarian teratomas. We describe the case of a 28-year-old woman diagnosed with anti-NMDAR encephalitis with mediastinal and bilateral ovarian teratomas in July 2019. The patient recovered following surgical management of the mediastinal mass and both ovarian teratomas, and immunotherapy. This case shows that teratomas can be found at multiple sites other than ovaries. Therefore, detecting teratomas using whole-body evaluation may be helpful for diagnosis and treatment.