Paediatrics: Acute diarrhoea

Acute diarrhoea

Normal stool frequency and consistency vary, e.g. breastfed infants may pass 10–12 stools per day, primary school children may pass stool from three times a day to once every three days. Diarrhoea is a change in con-sistency and frequency of stools with enough loss of fluid and electrolytes to cause illness. It kills 3 million children per year worldwide.

Acute diarrhoea

Causes

•   Infective gastroenteritis. Most common cause.

•   Non-enteric infections, e.g. respiratory tract.

•   Food hypersensitivity reactions.

•   NEC.

•   Drugs, e.g. antibiotics.

•   Henoch–Schönlein purpura (HSP).

•   Intussusception (<4yrs).

•   Haemolytic–uraemic syndrome.

•   Pseudomembranous enterocolitis.

Presentation

•   Fever +/– vomiting (infectious gastroenteritis).

•   Diarrhoea +/– bloody stools (colitis—infectious or non-infectious).

•   Dehydration and ‘fall’ consciousness.

Management

•   Assess hydration and vital signs, pallor (blood loss), abdominal tenderness, signs of associated illness (e.g. petechial rash in HSP).

•   Mild/moderate dehydration:

•   no tests necessary;

•   replace fluid and electrolyte losses with oral glucose–electrolyte based rehydration fluid, e.g. Dioralyte^® (UK).

•   Severe/shock dehydration:

•   U&E, creatinine, FBC, blood gas, stool M,C&S/virology, tests for specific disease (e.g. US in suspected intussuseption);

•   IV fluid and electrolyte replacement.

•   Anti-motility drug treatment is not recommended; it can be harmful, particularly in acute infection/inflammation.

•   Antibiotics are not indicated unless cause is proven, e.g. Yersinia or Campylobacter infection, parasitic infection, NEC, or proven bacteraemia/systemic infection.

•   Other treatment is disease specific. Some diarrhoeal processes require removal of the offending agent, such as in lactose intolerance or coeliac disease or allergic gastroenteritis. Others may require bowel rest or surgery, e.g. NEC or intussusception.

•   Once rehydrated, resume normal diet. Replace on going losses. Continue breast feeding. There is no evidence that prolonged starvation is beneficial in infective gastroenteritis.

• Prevent cross-infection with strict hand washing and barrier nursing. In the less developed world, breastfeeding, provision of clean water, and adequate sanitation are also important to reduce risk of infection.

Prognosis

•   The majority of cases, particularly if caused by infective gastroenteritis, make a complete recovery with appropriate treatment.