Changes in urinary monoamine excretion in hyperkinetic children.

The pathogenetic mechanisms of hyperkinetic syndrome are not clear and need further investigation. The aim of the study was to find certain features of monoamine metabolism that are characteristic of children with hyperkinetic syndrome (HKS) with special regard to different degrees of severity (i.e. mild HKS and severe HKS ). The levels of L-dopa, dopamine, noradrenaline, adrenaline, homovanillic, vanillylmandelic and 5-hydroxyindoleacetic acids were measured in daily urine of children (7-11 years old) with mild and severe HKS using fluorimetric and chromatographic methods. Severe HKS was characterized by a significant increase of L-dopa (by 186%), dopamine (by 201%) and adrenaline (by 160%) excretion but an unchanged excretion of noradrenaline compared with those with mild HKS. The study revealed principle differences in monoamine metabolism between the mild and severe forms of HKS which may be of importance in deciding different pharmacotherapeutic approaches to use in patients with HKS of differing severity. Copyright 2003 John Wiley & Sons, Ltd.