Psychosis: call a surgeon? A rare etiology of psychosis requiring resection

OBJECTIVE: Anti–N-methyl-d-aspartate receptor encephalitis is a rare but emerging cause of autoimmune encephalitis. Our objective is to present a case of this rare disease while highlighting the importance of an aggressive search for underlying malignancy as well as the common mischaracterization of primary psychiatric illness that occurs in these patients. METHODS: A young Caucasian female with no known psychiatric history presented with acute onset of seizures and psychosis. RESULTS: Magnetic resonance imaging abdomen and pelvis showed a 6-mm ovarian teratoma which was not visualized on initial computed tomographic scans. Pathology was consistent with a mature teratoma. Both serum and cerebrospinal fluid N-methyl-d-aspartate receptor antibodies were positive. CONCLUSION: An exhaustive search for underlying malignancy and specifically ovarian teratoma in young women should be completed in these patients. Diagnosis often is delayed given the prominent psychiatric manifestations and providers should be aware and strongly consider this in younger women with acute onset of neuropsychiatric symptoms.