The Role of Microbial Agents in the Etiology of Schizophrenia: An Infectious Hypothesis for Psychosis?

摘要

The ultimate cause of schizophrenia remains to be found, but it clearly includes a significant genetic ncomponent with an estimated heritability up to 85%. This suggests that genes may act as a predisposing factor upon which na variety of environmental risk factors can exert their deleterious effects, determining the emergence of psychotic nsymptoms. A recently growing interest has re-arisen on perinatal brain infections, which may increase the risk for nschizophrenia that can, in turn, be modified by hazardous genetic loading. This hypothesis is based on epidemiological nevidence, which has shown a significant exposure of affected individuals to infections with different pathogens. Such nresults are supported by tests carried out on animals. Another possibility is that there may be a link between a primary nmaternal infection and the subsequent development of schizophrenia in offspring. It is also been hypothesized that nmaternal antibodies against microorganisms may damage the fetal neural tissue, the area which is later found to be naffected by the lesion occurring in patients with schizophrenia. In the present chapter, we review recent evidence on the npotential role of infectious agents in the etiology of schizophrenia and discuss possible implications on the future of ndiagnostic, preventive and therapeutic issues.