When should an anti-NMDAR encephalitis be suspected in a pacient with symptoms of mood disorder.

Introduction: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, formally recognized in 2007, is more frequent than any other known paraneoplastic encephalitis. A 77.8% of patients are young female adults. In approximately 40% of the subjects, the disease is associated with an ovarian teratoma. The teratomaassociated cases are significantly more likely to present psychiatric symptoms than those without teratomas. Objectives: We report the case of a 37-year old female patient who was admitted in the Neurology ward after presenting neurological features in combination with symptoms of mood disorder, insomnia and aggressive behavior. We aim to review the clinical features that should lead us to suspect an anti-NMDAR encephalitis in a patient with psychiatric symptoms. Methods: A case reported is presented. A narrative review via scientific database (PubMed) was conducted. Results: Our patient had previously suffered a virus encephalitis. At the beginning, she presented a non-specific prodromal phase with headache and fever, as well as abnormal behavior. She was admitted at the Neurology ward for follow-up. Later on, appeared insomnia, agitation, disorganized thinking, manic symptoms and autonomic instability. Anti-NMDAR encephalitis was confirmed with the detection of antibodies against the GluN1 subunit of the NMDAR in the CSF of the patient and an ovarian teratoma was found and removed. Conclusions: When a patient without any psychiatric history presents a new-onset psychosis, especially in combination with dyskinesias, seizures, memory problems, decreased level of consciousness and/or catatonia, anti-NMDAR encephalitis should always be considered as a differential diagnosis. [ABSTRACT FROM AUTHOR]