Definition and causes of acute gastroenteritis

Acute gastroenteritis is identified by the presence of diarrhoea, which may be accompanied by fever or vomiting. Diarrhoea caused by acute gastroenteritis is generally defined as stools that are loose or liquid, or have a frequency of 3 or more stools in 24 hours(Guarino, 2018).

Acute gastroenteritis is most commonly caused by viral or bacterial pathogens, or is toxin-mediatedRiddle, 2016. Viral gastroenteritis is the most common cause of acute diarrhoea in Australia and worldwide. For more information, see Causes of acute infectious diarrhoea.

This topic does not cover the management of chronic diarrhoea, commonly defined as diarrhoea persisting for longer than 4 weeks. For information about the assessment and management of chronic diarrhoea, see Functional diarrhoea in adults.