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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

For six forms of endogenous psychosis, causal agencies were sought to establish endogenous, physical, and mental provocation. Endocrine causes were found most frequently, 17.5%, in mixed bipolar disorders, followed by cycloid psychoses, 8.5%, which in this respect appear to be closer to the mixed bipolar psychoses, than the unipolar forms at 4.4%. Among the physical causes, the difference in affective psychoses is not particularly great. Cycloid psychoses head the list at 9%. Among the mental causes, pure phase psychoses account for the greatest number, 12.7%, by a wide margin. The three unsystematic forms of schizophrenia revealed a slender link with their causes. Clear distinctions among the causes of the six forms were thus demonstrated.
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PMID:[Provoking endogenous psychoses]. 320 1

Cycloid psychoses constitute an original classification originally proposed by Leonhard and comprising clinical pictures intermediate between schizophrenic psychoses and bipolar disorders. The exact situation of these disorders in psychiatric classifications has been the subject of debate, and their existence is still questioned. Only schizo-affective psychoses have been accepted as autonomous. Treatment of cycloid psychoses most often consists of neuroleptics but also mood regulators, particularly those having anti-epileptic effects Lastly, prognosis of these disorders usually is not as poor as that of schizophrenia and is marked by a cycloid course, with symptom-free periods between episodes.
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PMID:[Cycloid psychoses]. 945 86

The diagnosis of cycloid psychosis has a long tradition in European psychiatry. However, it has been poorly assimilated within the DSM IV and ICD-10 diagnostic systems. Leonhard set the basis for the current conceptualization of the disorder, and Perris and Brockington developed the first operational diagnostic criteria. However, the two conceptualizations of the disorder are not the same and differ across a number of meaningful variables. Cycloid psychosis is a useful concept in that it possesses both clinical and predictive validity. Despite the high prevalence of mood symptoms and syndromes, cycloid psychosis does not equal schizoaffective disorder. Although a substantial body of evidence suggests that cycloid psychosis differs meaningfully from typical schizophrenia, it is less clear whether it differs from major mood disorders or represents an independent nosological entity. The existence of putative subtypes is also likely, and the differentiation between affective and nonaffective subtypes has received some support.
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PMID:Cycloid psychosis: an examination of the validity of the concept. 1752 13

Cycloid psychoses (CP) differ from schizophrenia regarding symptom profile, course, and prognosis and over many decades they were thought to be a separate entity within the psychosis spectrum. As to schizophrenia, research into the pathophysiology has focused on dopamine, brain-derived neurotrophic factor, and glutamate signaling in which, concerning the latter, the N-methyl-d-aspartate receptor plays a crucial role. The present study aims to determine whether CP can biochemically be delineated from schizophrenia. Eighty patients referred for psychotic disorders were assessed with the Comprehensive Assessment of Symptoms and History, and (both at inclusion and after 6 weeks of antipsychotic treatment) with the Positive and Negative Syndrome Scale and Clinical Global Impression. From 58 completers, 33 patients were diagnosed with schizophrenia and ten with CP according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and Leonhard criteria, respectively. Fifteen patients were diagnosed with other disorders within the psychosis spectrum. At both time points, blood levels of the dopamine metabolite homovanillic acid, brain-derived neurotrophic factor, and amino acids related to glutamate neurotransmission were measured and compared with a matched control sample. Patients with CP showed a significantly better response to antipsychotic treatment as compared to patients with schizophrenia. In CP, glycine levels were elevated and tryptophan levels were lowered as compared to schizophrenia. Glutamate levels were increased in both patient groups as compared to controls. These results, showing marked differences in both treatment outcome and glutamate-related variable parameters, may point at better neuroplasticity in CP, necessitating demarcation of this subgroup within the psychosis spectrum.
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PMID:Cycloid psychoses in the psychosis spectrum: evidence for biochemical differences with schizophrenia. 2753 15