The first case of Anti-N-methyl-d-aspartate receptor encephalitis (Anti-NMDAR encephalitis) associated with ovarian mucinous cystadenoma: A case report

Abstract

Objective: Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is a rare autoimmune and paraneoplastic encephalitis caused by the N-methyl-d-aspartate receptor antibody which is related to tumors, such as teratomas of the ovaries. To our knowledge, this is the first reported case of Anti-NMDAR encephalitis associated with ovarian mucinous cystadenoma. Case report: A 23-year-old woman with a flu-like illness, confused mental status, and behavioral changes presented to the hospital. A right-sided ovarian tumor was detected during the work-up and was suspected to be a teratoma that might have caused the encephalitis. A laparoscopic right salpingo-oophorectomy (RSO) was performed. Histopathological examination revealed a mucinous cystadenoma. She recovered gradually and had complete resolution of symptoms after surgical removal of the mucinous cystadenoma and immunotherapy. Conclusion: Even though anti-NMDAR encephalitis is caused by ovarian teratoma because it contains various types of tissues, ovarian tumors in anti-NMDAR encephalitis may not be limited to ovarian teratomas. Keywords: Anti-NMDAR encephalitis, Ovarian tumor, Mucinous cystadenoma