Enuresis is a common urinary problem that occurs in childhood and encountered by primary care physicians. Enuresis is defined as the involuntary discharge of urine. Enuresis can be further classified as being primary versus secondary, as well as nocturnal versus diurnal. Primary enuresis is the diagnosis for the patient with nocturnal enuresis who has never been dry for extended periods. In secondary enuresis, the patient has onset of urinary incontinence after a continuous period of at least 6 months of bladder control. Nocturnal enuresis is involuntary and undesirable discharge of urine during the night or sleep beyond the age of anticipated bladder control. Diurnal enuresis in contrast is involuntary discharge of urine while the child is awake.

The true incidence of enuresis is unknown because of underreporting. The timing of when a patient presents to the pediatrician with enuresis is variable and is dependent on that family’s concept of what is normal. It is estimated that 15% of 5-year-old children have primary nocturnal enuresis, never having achieved continence. Primary enuresis is twice as common as secondary enuresis; approximately 25% to 30% of children with enuresis have secondary enuresis. The incidence is increased in males 2:1 as compared to females. The rate of resolution amongst enuretics is approximately 10% to 15% per year, such that 5% of 10-year-old children and 1% of adolescents will remain incontinent. The view is the enuresis can be considered a clinical problem after the age of 4 or 5 years.

The typical sequence of developing continence in a child is to achieve nocturnal bowel control, daytime bowel control, daytime bladder control, and finally nocturnal bladder control. Urinary continence is developed through the enlargement of the child’s bladder capacity, voluntary control of the sphincter muscles, and finally voluntary control of micturition.