Assessment and treatment of the risk of psychosis in adolescents--a review.

Background: When psychosis first presents, and particularly in the case of schizophrenia, the guidelines recommend rapid institution of treatment with atypical antipsychotics. Two different clinical pictures can be observed: psychoses with acute onset and those with insidious onset. Acute cases (60% of the total) have a favourable course in 85% of young patients but where onset is insidious and the symptoms are predominantly negative, the course is poor in 25% of subjects. Since acute symptoms are relatively easy to diagnose, it is diagnosis of the 'insidious/negative' cases that represents a major challenge. Is such a diagnosis possible yet? How can we limit the number of false negatives and false positives with the attendant risk of stigma? What treatment should be administered?

Methods: Review of the literature (PubMed, PsycARTICLES, PsycINFO) and comparison with clinical practice here.

Results: Young people with a high risk of developing psychosis can be identified using scales such as SOPS (Scale of Prodromal Symptoms), PACE (Personal Assessment and Crisis Evaluation) or from the presence of neuroanatomical and genetic characteristics. Unfortunately, these tools are more specific for positive symptoms, and therefore identify a sub-population of young people at risk: those at Ultra-High Risk (UHR). It can be argued that effective treatment is available for these UHR young people to prevent the condition from developing into schizophrenia. On the other hand, the problem persists for young people presenting an insidious onset and predominantly negative symptoms: to date we have no real way of either screening them or assessing the efficacy of a treatment.

Conclusion: "Ultra-High Risk" patients are starting to represent a separate nosological entity. This entity is made up of young patients, most of whom have positive symptoms. If left untreated, the course will lead to seriously compromised social and psychological functioning. Rapid diagnosis and treatment for UHRs is therefore essential. In the future we need to refine our diagnostic tools to make them sufficiently specific and sensitive but also so that the widest category of "Risk Syndrome for Psychosis" includes young patients with mostly negative symptoms.