A Case of Anti-NDMA Receptor Encephalitis with Bilateral Ovarian Teratomas

Abstract

Anti-NMDA receptor encephalitis is an autoimmune encephalitis precipitated by antibodies generated against NMDA receptors, resulting in abnormalities in behavior, cognition, memory, and movement. Anti-NMDA receptor encephalitis most commonly occurs as a paraneoplastic disorder associated with an ovarian teratoma. While the symptomatic presentation of NMDA receptor encephalitis can be severe, removal of an associated ovarian teratoma generally causes significant improvement and the resolution of symptoms. Thus, accurate detection and early treatment are crucial for superior outcomes in these rare cases. We present a case of a 19-year-old African American female with a strong family history of epilepsy who was brought to the ED after having two weeks of headaches, multiple seizures over the course of the previous two days, and behavioral changes. An MRI of the brain was normal, but she had an elevated opening pressure. The constellation of symptoms and elevated lumbar pressure raised the suspicion of a paraneoplastic syndrome, and a subsequent CT of the abdomen and pelvis revealed a 5 x 4.2 cm ovarian cyst. Further examination of the features of the cyst with ultrasound revealed areas of calcification. IVIG treatment was started for treatment of a suspected paraneoplastic related encephalitis. After a discussion with neuroradiology about the differential, repeat MRI brain and an MRI abdomen revealed minimal hyperintensities within the temporal lobes bilaterally in the former and evidence of previously unidentified bilateral dermoid cysts in the latter. The patient tested positive for NMDA CSF and underwent left salpingoophorectomy and right ovarian cystectomy. After treatment, she returned to her baseline but still experiences spontaneous jerking movements. This case report discusses the early use of IVIG, communication with radiology, and the importance of maintaining a broad differential. After a thorough review of the literature, there are very few cases in which NMDA receptor encephalitis has presented with bilateral ovarian teratomas.