Case Report: Surgical resection of ovarian teratoma in anti-NMDAR encephalitis complicated by severe pneumonia.

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is one of the most recognized forms of autoimmune encephalitis. We report the case of a 25-year-old woman with ovarian teratoma-associated anti-NMDAR encephalitis complicated by severe pneumonia. Despite treatment at multiple hospitals, she remained comatose with involuntary perioral myoclonus and severe pulmonary infection while intubated. After aggressive anti-infective therapy at our center, her condition deteriorated, and extubation failed; subsequent tracheostomy stabilized the infection and allowed uneventful laparoscopic removal of the ovarian teratoma. Postoperatively, consciousness returned, convulsions ceased, and pulmonary infection continued to improve. The patient was discharged in good condition. Early screening for ovarian teratomas is essential. When teratoma-associated anti-NMDAR encephalitis presents with severe pneumonia, aggressive infection control, meticulous airway management, and timely surgical resection combined with immunotherapy can substantially improve clinical outcomes.