Non-schizophrenic psychotic disorders constitute a relatively small proportion of all child and adolescent neuropsychiatric disorders (Steinberg, 1985). This group comprises mania, major depression with psychotic features, bipolar disorder, schizoaffective disorder and organic and toxic psychosis, including those that are precipitated by substance abuse (Gillberg et al., 1986). Most of these conditions have reported onset at, or after, age 18 years and so fall outside the scope of this book. Nevertheless, premorbid emotional and behavioural abnormalities are common in the histories of people diagnosed in the categories mentioned (Hellgren, Gillberg & Enerskog, 1987; McClellan, Werry & Ham, 1993), and a number of investigators have reported on at least some individuals in the 6–17 year-old age range with any one of these diagnoses.

Mania

There is limited evidence for discrete episodes of adult type mania in prepubertal children, but some authorities believe that an atypical form of bipolar disorder characterized by periods of motor overactivity, inattention, behavioural disturbance, mood volatility and/or withdrawal occurs in genetically vulnerable children (Carlson, 1984). Clinical observations suggest that sleep problems may also be common in this group. There is anecdotal support for the notion that intermittent prostitution or promiscuous behaviour may signal underlying remitting mania. Uncontrolled studies suggest that children showing such symptoms may be responsive to treatment with lithium (Weller et al., 1986).

The existence of mania is considerably better validated in adolescents, and, according to one study, its prevalence in 13–19 year-olds is at least 3 in 10000 (e.g. Gillberg et al., 1986).