Nonaffective acute psychoses: uncertainties on the way to DSM-V and ICD-11.

Since the early 20th century, a group of nonaffective psychoses with acute onset and brief duration have been described in different countries under various names, including cycloid psychosis, bouffée délirante, and reactive psychosis. These psychoses share several characteristics, including benign course, greater prevalence in women than men and in developing countries than in industrialized countries, and high prevalence of premorbid psychological and physiologic stressors. However, the variations in names and minute details of symptomatology have overshadowed the basic similarities across these various descriptions. Confusion in classification persists in the two contemporary diagnostic systems, the DSM-IV and the ICD-10. We believe that most cases of these psychoses could be captured under a broad, unified category of nonaffective psychosis with acute onset and brief duration, and urge the authors of the upcoming revisions of the DSM and ICD to create such a category. A unified diagnostic category for these disorders would reduce unnecessary fragmentation in the diagnostic systems and assist in the progress of research on these rare conditions.