title: First-episode psychosis in a 15 year-old female with clinical presentation of anti-NMDA receptor encephalitis: a case report and review of the literature.
abstract: BACKGROUND
  Anti-NMDA receptor encephalitis is an autoimmune disease that was identified in 2007, and manifests in a stepwise manner with psychiatric, neurological and autonomic symptoms. The disease is caused by autoantibodies against NMDA receptors. It can have a paraneoplastic origin, mainly secondary to ovarian teratomas, but it can also be unrelated to the tumor. This disease can affect both sexes and all ages.
  
  
  METHODS
  Here, we present a case of a 15 year-old female adolescent with first-episode psychosis with anti-NMDA receptor encephalitis not related to tumor, which manifested with delusion, hallucinations, panic attacks, agitation, and neurological symptoms, and later with autonomic instability. She was treated with immunotherapy and psychiatric medication resulting in improvement of her main psychiatric and neurological symptoms.
  
  
  CONCLUSIONS
  Our main objective in presenting this case is to alert clinicians to this challenging and recent disease that has a clinical presentation that might resemble a functional psychiatric condition and can be underdiagnosed in the context of child and adolescent psychiatry.
authors.affiliation: Unit of Child and Adolescent Psychiatry, Department of Psychiatry, Hospital Vila Franca de Xira, R. do Parque Res. dos Povos 1, 2600-009, Vila Franca de Xira, Portugal.
authors.forename: Maria
authors.initials: M
authors.lastname: Moura
authors.affiliation: Department of Psychiatry, Hospital Vila Franca de Xira, R. do Parque Res. dos Povos 1, 2600-009, Vila Franca de Xira, Portugal. amilcarss@gmail.com.|Faculty of Medicine, Institute of Pharmacology and Neurosciences, University of Lisbon, Lisbon, Portugal. amilcarss@gmail.com.|Unit of Neurosciences, Institute of Molecular Medicine, University of Lisbon, Av. Professor Egas Moniz, 1649-028, Lisbon, Portugal. amilcarss@gmail.com.
authors.forename: Amilcar
authors.identifier: http://orcid.org/0000-0001-9537-4782
authors.initials: A
authors.lastname: Silva-Dos-Santos
authors.affiliation: Child and Adolescent Psychiatry Unit, Hospital Dona Estefânia-Centro Hospitalar de Lisboa Central, R. Jacinta Marto, 1169-045, Lisbon, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Afonso
authors.affiliation: Department of Psychiatry, Hospital Vila Franca de Xira, R. do Parque Res. dos Povos 1, 2600-009, Vila Franca de Xira, Portugal.|CEDOC, Chronic Diseases Research Centre, Nova Medical School, Faculdade de Ciencias Médicas, New University of Lisbon, Campo Mártires da Pátria 130, 1169-056, Lisbon, Portugal.
authors.forename: Miguel
authors.initials: M
authors.lastname: Talina
mesh_terms: D000293:Adolescent; D014151:Anti-Anxiety Agents / Q000627:therapeutic use; D060426:Anti-N-Methyl-D-Aspartate Receptor Encephalitis / Q000150:complications / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology*; D000928:Antidepressive Agents / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D001323:Autoantibodies / Q000096:biosynthesis; D005260:Female; D006801:Humans; D011618:Psychotic Disorders / Q000150:complications / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000276:immunology; D000069283:Rituximab / Q000627:therapeutic use*
chemical_list: D014151:Anti-Anxiety Agents; D000928:Antidepressive Agents; D014150:Antipsychotic Agents; D001323:Autoantibodies; D016194:Receptors, N-Methyl-D-Aspartate; D000069283:Rituximab
keywords: Adolescent; Anti-NMDA receptor encephalitis; Case report; First-episode psychosis; Psychosis