Clinical enuresis phenotypes in familial nocturnal enuresis

The objective of the current study was to identify the associations between phenotype and genotype in children with nocturnal enuresis. Of the total of 167 wetting children, aged 5-10 years, without neurological or structural forms of incontinence, 110 were nocturnal enuretics. The examinations included a full psychiatric and psychological assessment, a paediatric and neurological examination, a family history with pedigree, ultrasonography, uroflowmetery, urinanalysis and bacteriology. Children with secondary nocturnal enuresis (n = 28) had a significantly higher rate of behavioural disorders, life events and continuous psychosocial stress than those with primary nocturnal enuresis (n = 82). Of the latter group, children with primary monosymptomatic nocturnal enuresis (n = 50) had an especially low rate of behavioural problems, when in comparison to primary non-monosymptomatic nocturnal enuretics (n = 32). Formal genetics point to a high genetic predisposition to nocturnal enuresis in all subgroups. Linkage studies to markers on chromosomes 8, 12 and 13 demonstrate both clinical, as well as genetic heterogeneity in nocturnal enuresis.