Change in Bowel Habit - Adult Leeds

*Investigations for acute diarrhoea
Investigations are not always necessary for adults presenting with acute diarrhoea.
Stool sample – send if:

  • person is systemically unwell, eg fever, dehydration
  • there is blood or pus in the stool
  • reassurance is required, as diagnosis of infection may exclude other pathologies
  • the person is immunocompromised
  • in certain situations, such as a flare of IBD, patients are felt to be at greater risk of complicating infection, and stool samples for MC+S and C. difficile would be indicated
  • Ova, cysts and parasites:
    Diarrhoea occurs after foreign travel to anywhere other than Western Europe, North America, Australia, or New Zealand
  • request tests for ova, cysts and parasites
  • send 3 specimens 2-3 days apart as parasites are shed intermittently

The only time "3 consecutive stools" should be requested is when investigating for Ova, Cysts and Parasites (OCP). 3 samples
are recommended because the yield tend to be quite low hence 3 separate samples improves the chances of finding the causative pathogen. This can be done by giving the patient the 3 request forms and specimen pots but asking them to fill in the date and time of collection before bringing them back to the specimen drop off point. The main indications for this would be a history of foreign travel/parasitic contact or, for Cryptosporidium, countryside/farm exposure etc.

  • Clostridium difficile:
    There are some clear risk factors for community acquisition (antibiotic expose, healthcare exposure, nursing/care home resident, exposure to children <2yrs etc.) but there is a great deal unknown about the epidemiology of community acquired CDI.

Local Leeds microbiology guidance suggests sending a sample for C. difficile testing in everyone of 65 and over and those <65 years should have a good reason not to be tested. The test has a very low false positive rate hence there should not be a concern that testing more will increase the number of cases without benefiting the patient.


Consider Blood Test
FBC, UE, LFT, CRP

Advice for collecting a stool sample:

  • do not mix urine with the stool sample
  • use a wide mouth container in the toilet bowl, eg:
    • potty
    • clean empty plastic food container
  • alternatively, put clean plastic wrap or newspaper over the toilet seat opening
  • use the spoon in the lid of the collection tube to place small scoopfuls of stool into the tube from areas which appear bloody, slimy, or watery
  • do not overfill
  • try not to spill stool on the outside of the tube
  • screw collection tube lid on tightly
  • label collection tube with:
    • name
    • date of birth
    • date of collection