eng Science and Education Publishing American Journal of Medical Case Reports 2374-216X 2021-04-06 9 7 354 357 10.12691/ajmcr-9-7-3 AJMCR2021973 article Eiad Habib eiadhabib8@gmail.com 1 Jay Patel 2 3 Connor Kerndt 3 3 Dan Summers 3 3 TaLawnda Bragg 3 3 Alfaisal University College of Medicine, Riyadh, Saudi Arabia 11533 Department of Internal Medicine, Spectrum Health Butterworth Hospital, Grand Rapids, Michigan, USA 49503 Anti-N-methyl-D-aspartate (NMDA)-receptor encephalitis is a syndrome of psychiatric symptoms and neurologic sequelae that is commonly associated with an ovarian teratoma. The antagonism of cerebral NMDA receptors disrupts normal brain activity causing acute onset psychological disturbances including mania, psychosis, or anxiety. Due to the rarity of the condition, diagnosis may be delayed as other common disorders such as primary psychiatric disorders or infectious encephalitis are ruled out. With rapid diagnosis and management, including resection of the tumor and immunotherapy, positive outcomes may be achieved. We present the case of a 25-year-old female with neuropsychiatric manifestations and an ovarian teratoma who was subsequently diagnosed with anti-NMDA-receptor encephalitis. http://pubs.sciepub.com/ajmcr/9/7/3/ajmcr-9-7-3.pdf paraneoplastic anti-NMDA receptor encephalitis ovarian teratoma