Examqo › Examqo library › Pediatrics › Paediatric nephrology and gastroenterology · IMLE
Nocturnal enuresis
Nocturnal enuresis is wetting during sleep from age 5; the common form is primary and "monosymptomatic" (no daytime symptoms), with a strong family tendency and spontaneous resolution — and the two effective treatments are the enuresis alarm and desmopressin.
Why it matters in the exam
The question describes a 7-year-old who wets at night and is dry by day, with a parent who wet as a child, a normal examination and a normal urinalysis — and asks for the treatment. The diagnosis is primary monosymptomatic enuresis, and the answer is explanation and reassurance, behavioural steps, and then an alarm (most effective long term) or desmopressin (fast-acting, suitable for nights away, frequent relapse on stopping).
The only basic test needed is a urinalysis — looking for glucose (type 1 diabetes), low specific gravity (diabetes insipidus or kidney disease) and infection. Secondary enuresis — after a dry period of at least 6 months — needs a search for a cause: urinary infection, diabetes, constipation, sleep apnoea, psychological stress or abuse. Daytime symptoms (urgency, daytime wetting, frequency) define non-monosymptomatic enuresis, and there bladder function and constipation are treated first.
Desmopressin carries a risk of hyponatraemia and water intoxication, so fluids are restricted from one hour before the dose until 8 hours after it, and a tablet or melt is used — not a nasal spray for enuresis. Punishment is not treatment and causes harm, including to the child's self-esteem. Each year about 15% of children stop wetting on their own, so choosing not to treat yet is a legitimate option when the wetting does not bother the child and family.
Key points
- Night wetting from age 5 is enuresis.
- Basic work-up: history, examination and urinalysis.
- Secondary enuresis or daytime symptoms — look for a cause.
- The alarm is most effective long term; desmopressin is fast.
- Desmopressin — restrict evening fluids because of hyponatraemia.
Summary table
| Type | Definition | Work-up | Treatment |
|---|---|---|---|
| Primary monosymptomatic | Night wetting from age 5, no daytime symptoms, never dry | History, examination, urinalysis | Reassurance, behavioural steps, alarm or desmopressin |
| Non-monosymptomatic | Night wetting with frequency, urgency or daytime wetting | Voiding diary, assessment for constipation | Treat the bladder and constipation first |
| Secondary | Wetting after at least 6 dry months | Urine for glucose and infection, questions about stress and abuse | Treat the cause |
| Suspected organic cause | Thirst and polydipsia, weight loss, snoring, weak stream | Glucose, specific gravity, sleep assessment, ultrasound | According to the cause |
In the full version for subscribers
- A simple algorithm
- Memory aid
- Exam traps
- 5 review cards
- Enough for IMLE
The full version is open to subscribers of: Pediatrics, Medical licensing exam (IMLE), Family medicine, Urology.
Subscriber? Read the full topic Plans and prices 25 free questions
Sources
- International Children's Continence Society (ICCS) standardisation and practical consensus on nocturnal enuresis, 2020 update — Definitions, evaluation and first-line treatment
- Nelson Textbook of Pediatrics, 22nd edition (2024) — Enuresis and Voiding Dysfunction
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.