Acute Transient Psychoses and their Differentiation from Schizophrenia

Current psychiatric classifications include provisional categories for acute transient psychoses such as ICD-10 ‘ Acute and transient psychotic disorders’ (ATPD) and DSM-IV-TR ‘ Brief psychotic disorder’ . Following on from an account of earlier concepts such as bouffee delirante, cycloid psychosis and the reactive and schizophreniform psychoses, this paper describes the process whereby they were subsumed under the heading of ATPD, then sets out research comparing ATPD and schizophrenia in terms of epidemiology, clinical features, course and outcome. Papers published between 1 January 1993 and 30 June 2011 were found through searches in Medline, PsychInfo and Google Scholar. Further references were identified from book chapters and reviews of the topic. Acute onset, polymorphic symptoms, early remission, absence of premorbid dysfunctions and association with female gender are features reported to distinguish ATPD from schizophrenia. However, case identification may be difficult owing to the fleeting nature of the clinical phenomena ATPD encompasses, and high rates of change of diagnosis in subsequent episodes. It is concluded that the lack of clearly defining symptoms and poor predictive validity of ATPD argue against a sharp demarcation from schizophrenia.