A woman with an ovarian teratoma may develop an autoimmune encephalitis due to autoantibodies targeting the N-methyl-D-aspartate (NMDA) receptor.
Target of autoantibody: usually the GluN1 subunit of the NMDA receptor
Clinical features:
(1) typically involve a woman less than 45 years of age
(2) rapidly progressive (over a few weeks)
(3) abnormal behavior (psychosis, delusions, hallucinations, agitation, aggression, catatonia)
(4) insomnia
(5) speech dysfunction
(6) dyskinesias OR abnormal movements OR rigidity
(7) memory deficit
(8) autonomic instability
(9) decreased level of consciousness
(10) seizures
(11) cerebellar ataxia
(12) hemiparesis
Laboratory findings:
(1) presence of an autoantibody targeting the NMDA receptor, typically anti-GluN1, in serum and CSF
(2) presence of an ovarian tumor
The clinical symptoms improve following resection and therapy for the teratoma.
Other tumors associated with anti-NMDAR encephalitis:
(1) testicular germ cell tumor
(2) small cell lung carcinoma
(3) neuroblastoma
