Anti-NMDA-receptor encephalitis: an adolescent with an ovarian teratoma.

Background: Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis has been reported to be associated with ovarian teratomas. In many patients, surgical excision has resulted in improvement.

Case: A previously healthy 14-year-old girl presented with confusion which later evolved into a comatose state. Imaging revealed an adnexal mass which was surgically removed and confirmed to be a mature teratoma. Her cerebral spinal fluid was positive for antibodies to NR1/NR2 heteromers of NMDA receptors.

Comments: Cystic teratomas are one of the most common benign ovarian lesions in children and young women. While an association of ovarian teratomas and paraneoplastic encephalitis is published in the neurologic literature, this association needs to be clarified for the practicing gynecologist who may be asked to consult on these patients.