A stool test is done to assess the health of your bowel and your gut. It analyses your poo as there are many things it can tell a doctor about your overall health.
There are two main groups of stool tests: those that look for illness and diseases and others that look more at the health of the gut and microbiomes. Diseases like inflammatory bowel disease such as Crohn’s and ulcerative colitis can be detected by a stool sample, and tests to pick up microscopic blood from the gut – blood you can’t visibly see – can help in early detection of cancer. Certain infections can also be picked up too if the stool sample is looking at bacteria, ova, cysts, or parasites like worms. There are also stool samples that can diagnose if you have a condition called fat malabsorption or if your pancreas is not producing enough enzymes.
Certain symptoms may prompt your doctor to arrange a stool sample. Symptoms such as blood or mucus in your stool, persistent change in your bowel habit (constipation or diarrhoea), unexplained weight loss, stomach pain or cramping and even persistent nausea can all indicate different types of illnesses that can be diagnosed by a stool sample. If you have acute diarrhoea, possibly gastroenteritis, your doctor may request a stool test to check for certain serious infections or parasites, especially if you picked it up from somewhere abroad or have been admitted to hospital.
Although stool tests can provide a good amount of information, there is still a lot that they cannot diagnose. For example, gluten insensitivity or food intolerances and allergies. Some private providers do stool tests that can diagnose conditions like small intestine bacterial overgrowth, candida overgrowth or leaky gut. It is important to be aware that these are not offered on the NHS as the validity of these results for these conditions is still unknown.
You’ll be given a special container with a lid that you can write your details on. You’ll be advised to catch your stool in a clean disposable container or onto tissue if your poo is not leaky and use the spatula provided to scoop some of the stool into the container. Make sure your poo doesn’t touch the inside of the toilet and avoid mixing your urine and poo together. Seal the container and return it to your doctor’s office as soon as possible. And don’t worry, the reception staff are very used to handling specimens, just make sure you’ve screwed the top tight and sealed it in the bag provided.