Definition

• Diurnal (daytime) vs nocturnal (nighttime)
• Approximately 15% of nocturnal enuresis also have daytime wetting
• Primary vs secondary
• Primary (80%)- never had a dry period before
• Secondary (20%) - Have been dry at least 6 months before wetting again

Natural history

• Incidence - 15-25% in 5-year old children; M:F 3:2 ratio
• Spontaneous cure rate of 15% per year
• Etiology - often unclear
• Some genetic component (68% concordance in monozygotic twins)
• Delay in maturation of CNS (bladder stretch receptors do not reach the brain, so bladder contraction is not inhibited)
• Low functional bladder capacity
• Sleep disorders, upper airway obstruction
• Psychological factors
• UTI
• Nocturnal polyuria - normally will increase ADH at night to concentrate urine, so those who make less ADH at night have higher urine volumes

History

• Primary or secondary?
• Frequency/timing - how often, which days of the week, what time
• Any daytime symptoms
• Psychosocial history, precipitating factors
• Developmental milestones
• Voiding diary

• UA to screen for infection, poor concentration
• Secondary enuresis needs additional workup eg RBUS

• Behavioral
• Void before bed
• < 4-6 oz fluid after dinner
• Waking the child at night to void usually doesn't help
• Pharmacologic
• DDAVP aka synthetic ADH
• starting dose 0.2 mg qhs, can up to 0.4 or 0.6 mg (max)
• Side effects - hyponatremia, seizure
• Counsel to limit overall fluid intake
• If need to drink a lot during the day (exercise, or sick), then don't take DDAVP at night