Anti-N-methyl-D-aspartate receptor encephalitis with occult ovarian teratoma: a case report.

A 31-year-old female was admitted with headache, memory disturbance, abnormal behavior, incontinence, confusion, complex partial seizures, decreased oxygen saturation and increased temperature. Anti-NMDAR antibodies were positive in serum and cerebrospinal fluid. Subsequently, a regimen of immunotherapy that included intravenous immunoglobulins, methylprednisolone, plasma exchange and their combinations were used. But the treatment was ineffective. Though both transvaginal ultrasonography and abdominal CT scan contrast revealed left ovarian cyst, the patient had left oophorectomy. And during surgery we found a small cyst mass contained fat-like liquid with air in her left ovarian. Pathological examination demonstrated mature cystic teratoma accompanied with brain tissue. She has made gradual and steady improvement after surgery, but not fully recovery. By combining this case with previous studies of others, we further discuss the clinical characteristics, treatment and prognosis of the disease.