Cycloid Psychoses: Clinical Symptomatology, Prognosis, and Heredity

Resumo

The development of the concept of cycloid psychoses goes back to the problem of “atypical psychoses” which arose from Kraepelin’s dichotomy of endogenous psychoses1. It concerned those forms of psychoses which could be assigned neither to dementia praecox nor to manic-depressive illness. One strategy for a solution of this problem was the broadening of the concept of schizophrenia as inaugurated by Bleuler (1911). Schizophrenia was then thought to include lots of clinical conditions with entirely different cross-section- al symptomatology, long-term course and outcome, thus considerably reducing the heuristic value of the diagnosis. Furthermore, reliable prognoses became impossible according to Bleuler’s concepts. Inevitably, the idea was generated that there might be a nosologically independent group of endogenous psychoses in addition to schizophrenias and manic-depressive illness. Based upon the previous work of Wernicke and Kleist, Leonhard (1999) further established the concept of cycloid psychoses. Rejecting nosological hybridisation, the independency of these psychoses was emphasized. Representing one of the three main groups in his subdivision of psychoses with “schizophreniform” symptomatology, Leonhard meticulously elaborated on precise clinical diagnostic criteria or cycloid psychoses. In the current diagnostic manuals, those psychoses spread over various diagnostic entities like bipolar affective disorder, schizoaffective disorder, acute polymorphic psychotic disorder (ICD), brief psychotic disorder (DSM), or even schizophrenia, if 1st-rank symptoms are observed for more than one month.