[Nocturnal enuresis in children].

After allergic disorders, nocturnal enuresis is the most common chronic childhood condition. Recent research has yielded abundant new knowledge about the condition, especially about its aetiology and pathophysiology, and the psychological consequences. A hereditary background has been substantiated by the identification in genetic linkage studies of areas in chromosomes 12 and 13 that are manifestly associated with bedwetting, though genotype expression in the phenotype appears to be complex and heterogeneous. Pathophysiologically, findings in current intensive research suggest three interactive factors to be involved: (i) relative nocturnal polyuria, due to insufficient antidiuretic hormone release during sleep in pre-teenagers, and due to renal tubular dysfunction in adolescents and adults; (ii) reduced nocturnal bladder capacity, especially in the 33 per cent of cases which do not respond to desmopressin treatment; and (iii) the patient's inability to waken in response to signals from a full bladder. Recent findings have also confirmed previous reports that with very few exceptions bedwetting is not caused by psychological factors. On the contrary, the condition causes psychological problems manifested in reduced self-esteem, shame and guilt, though self-esteem is restored by successful treatment. Active treatment should be started as soon as the child is ready to receive it, the main options being an enuresis alarm, desmopressin, or a combination of the two. If reduced bladder capacity is suspected, treatment with a detrusor relaxant should be included.