Open AccessCycloid psychosis as a psychiatric expression of anti‐NMDAR encephalitis. A systematic review of case reports accomplished with the authors' cooperation
Author(s) -
Giné Servén Eloi,
Boix Quintana Ester,
Martínez Ramírez Maria,
Guanyabens Buscà Nicolau,
Muriana Batiste Desiree,
Guasp Mar,
Torres Rivas Cristina,
Davi Loscos Eva,
Casado Ruiz Virginia
Publication year - 2021
Publication title -
brain and behavior
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.915
H-Index - 41
ISSN - 2162-3279
DOI - 10.1002/brb3.1980
Subject(s) - psychosis , encephalitis , psychiatry , psychology , mood , mania , phenotype , medicine , schizophrenia (object oriented programming) , pediatrics , bipolar disorder , immunology , biology , biochemistry , virus , gene
Objective We reviewed the psychotic symptoms of anti‐NMDA receptor encephalitis (NMDARE) to differentiate its presentation from those found in a primary psychiatric disorder. We hypothesized that the cycloid psychosis (CP) phenotype would be a frequent clinical presentation in the psychiatric phase of NMDARE. Method A systematic literature review in PubMed of all case reports published on NMDARE was performed from database inception to March 2020. We included all cases where psychotic symptoms were reported and whose diagnoses were confirmed by the presence of anti‐NMDAR antibodies in the cerebrospinal fluid (CSF). An email including a short test (CP phenotype, Perris and Brockington's criteria) was sent to all case report authors asking them to describe the psychotic symptoms. Results We identified 335 case reports fulfilling our criteria, and the authors of 200 replied. Our analyses were based exclusively on those answers and data extracted from the articles. Median patient age was 25 years (+‐11.4), 81% were female, and 39% had an ovarian teratoma. A complete CP phenotype was identified in 175 patients (87%). These were acute psychotic episodes with a sudden onset and a fluctuating clinical pattern mostly characterized by confusion (97%), delusions (75%), hallucinations (69%), motility disturbances (87%), and mood oscillations (80%). Conclusion The complete CP phenotype was frequently the expression of psychotic symptoms in NMDARE. We suggest that patients with a first psychotic episode who initially exhibit the CP phenotype should undergo CSF analysis to determine whether antibodies against neuronal cell surface or synaptic receptors are present to rule out a possible diagnosis of autoimmune encephalitis.