rules of thumb
Last reviewed 01/2018
The following guidelines may help in the differential diagnosis of diarrhoea:
- copious watery diarrhoea suggests an organic aetiology
- nocturnal diarrhoea suggests an organic aetiology - patient wakes up in the night needing to open bowels
- frequent passage of small amounts of faeces suggests functional bowel disease, e.g. irritable bowel syndrome
- bloody diarrhoea implies colonic disease, often inflammatory bowel disease or carcinoma, or an invasive infective diarrhoea, e.g. Campylobacter jejuni
- acute diarrhoea often has an infective aetiology