Nocturnal enuresis (bedwetting)

Nocturnal enuresis, or bedwetting, is an old but still prevalent clinical problem in childhood and adolescence. Recent research has helped to correct some traditional misconceptions and unveil the underlying pathophysiological mechanisms. This article reviews recent advances in our understanding of the pathophysiology and current management strategy for enuresis.

Nocturnal enuresis is a heterogeneous disorder with various underlying pathophysiological mechanisms, causing a mismatch between the nocturnal bladder capacity and the amount of urine produced during sleep at night, in association with a simultaneous failure of conscious arousal in response to the sensation of bladder fullness. Children with increased nocturnal urine production usually have a good response to desmopressin therapy. Patients with a small bladder almost invariably have various types of occult bladder dysfunction, but otherwise have a completely normal circadian rhythm of urine production. These patients generally have a poor response to desmopressin treatment, but would benefit more from combination therapy with enuretic alarm, urotherapy and antimuscarinic agents in addition to desmopressin.

Various factors can potentially influence the balance between nocturnal urine production and functional bladder capacity. Different types of bladder dysfunction, resulting in a small nocturnal bladder capacity, probably contribute significantly to the pathogenesis, particularly in those with treatment failure and refractory symptoms. As different clinical subgroups may have different responses to treatment, it is necessary to distinguish these subgroups before a decision on the specific treatment protocol can be made. These new insights have an important bearing in our future management strategy for bedwetting.