Current concepts in the validity, diagnosis and treatment of paediatric bipolar disorder.

Despite ongoing controversy, the view that paediatric bipolar disorder is rare or non-existent has been increasingly challenged not only by case reports but also by systematic research. This research strongly suggests that paediatric bipolar disorder may not be rare but that it may be difficult to diagnose. Since children with bipolar disorder are likely to become adults with bipolar disorder, the recognition and characterization of childhood-onset bipolar disorder may help identify a meaningful developmental subtype of bipolar disorder worthy of further investigation. As recommended by Robins and Guze [American Journal of Psychiatry (1970), 126, 983-987], a psychiatric disorder may be considered a valid diagnostic entity if it can be shown to have differentiating features, evidence of familiality, specific treatment responsivity and a unique course. The goal of this article is to review our work and the extant literature within this framework to describe the evidence supporting bipolar disorder in children as a valid clinical diagnosis.