Vomiting and diarrhoea

16 Oct 07

The causes of vomiting and diarrhoea in primary care include the following.

Physiological: breast-fed babies (with loose, often explosive, mustard grain stools), posseting in babies, reflux (usually only vomiting), intermittent loose stools related to diet or irritable bowel syndrome

Gastrointestinal infection: diarrhoea and/or vomiting. Consider pseudomembranous colitis if there is a recent history of antibiotics. Consider temporary cow’s milk intolerance in babies with over two weeks diarrhoea.

Other infection: a common cause of vomiting in children for example otitis media, tonsillitis and septicaemia.

Acute intra-abdominal disease: intussusception (admit), appendicitis (admit), acute obstruction (abdominal distension and vomiting – admit), pyloric stenosis (usually in babies less than 12 weeks old – vomiting only, admit).

Constipation: Usually overflow of soft stool with or without vomiting.

Inflammatory bowel disease or malabsorption: diarrhoea only.

Drugs/toxins: for example opiates (vomiting), diclofenac (diarrhoea).

Other causes: elevated intracranial pressure, head injury, anorexia/bulimia, migraine, travel/motion sickness, cerebellar disease, Ménière’s disease/ labyrinthitis, pregnancy, metabolic (ketoacidosis, uraemia), carcinomatosis. Consider haemolytic uraemic syndrome if child is passing blood in stool.

History

Determine nature and duration of symptoms. If diarrhoea – is there blood or mucus in the stool? If vomiting – colour and frequency, ability to retain food/fluids, nature of vomitus, presence of blood or ‘coffee grounds’, relationship to eating. Contact with anyone else with similar symptoms? History of recent foreign travel? Other symptoms?

Examination

Level of hydration: BP with or without postural drop. Pulse. Sunken eyes, dry tongue, reduced skin turgor and sunken fontanelle in babies are all late signs.

Abdomen: masses, distension, tenderness, bowel sounds, hepatomegaly.

Look for other sources of infection such as ENT, chest infection, UTI.

Management

Treat any identified cause.

If diarrhoea then send a stool sample for M, C and S if there is fever, blood in stool, recent return from a tropical climate, immunocompromised, resident in an institution and/or persists for more than seven days.

Encourage rehydration through small, frequent amounts of clear fluid with or without commercial rehydration salts like Dioralyte.

Reserve antidiarrhoeals such as loperamide for patients in whom diarrhoea would be a problem such as immobility, travel or work. Never give children antidiarrhoeal agents.

Admit anyone who is dehydrated but when fluid replacement is not possible such as someone with severe vomiting or a child or elderly person who is refusing to drink.

Stick to a bland food diet avoiding dairy products until diarrhoea has settled. Babies who are breast-fed or have not been weaned should continue their normal milk.

If no cause is found and diarrhoea lasts longer than three weeks – or there are any atypical features – refer for urgent investigation or admit.