Gastroenteritis in children
Introduction
Gastroenteritis is a common reason for paediatric emergency visits, especially in children under 5. It is an acute, usually self‑limiting infection of the gastrointestinal tract (viruses, bacteria or parasites) characterised by sudden onset diarrhoea with or without vomiting.
Emergency priorities are: exclude other serious causes, recognise and treat dehydration and shock, provide appropriate rehydration (prefer oral where possible), and decide on admission or safe discharge.
Clinical practice should follow NICE guidance (CG84) for assessment and rehydration and Resuscitation Council UK / PALS for shock and resuscitation.
Definitions and natural history
- Vomiting: forceful ejection of gastric contents (distinct from effortless regurgitation in infants).
- Diarrhoea: passage of loose or watery stools, usually with increased frequency or volume.
- Typical course (NICE): diarrhoea commonly lasts 5-7 days (usually resolves within 14 days); vomiting commonly lasts 1-2 days (usually resolves within 3 days). Use these figures when safety‑netting carers.
Epidemiology and causation
- Viral causes predominate in young children. Historically rotavirus was the leading cause of severe gastroenteritis in under‑5s in the UK; the national infant rotavirus immunisation programme (Rotarix introduced July 2013) produced a marked reduction in cases and admissions. Surveillance was disrupted by the COVID‑19 pandemic-consult UKHSA/GOV.UK for current local patterns.
- Norovirus causes many community and institutional outbreaks and is common in older children and adults.