Children who are inappropriately wet are common. A variety of underlying causes can share this symptom, and it can be a frustrating problem for children, their families, and their physicians. Fortunately, the evaluation is straightforward, and usually a cessation or an improvement of the wetting can be achieved. Most children can be successfully managed by a thorough history, physical examination, and an understanding of the normal development of urinary continence. Rarely are invasive or complex procedures or imaging needed.

It has been customary to categorize children who wet by when the wetting occurs. Nocturnal or monosymptomatic enuretic children wet only at night, whereas diurnal enuretic children wet day and night. Primary enuretic children have never been dry and secondary enuretic children were dry for at least 6 months to a year before beginning incontinence. For this discussion, a mixed classification system is used. It is based on time of wetting, underlying cause, and presentation (Table 1). After a general review, each type is discussed, with the emphasis given to the most common form: nocturnal enuresis.