Faecal calprotectin and stool tests

Category: Digestive Tests & Procedures · All digestive tests & procedures

What it is

Stool tests analyse a small sample of faeces in the laboratory. Key examples are faecal calprotectin, which reflects inflammation in the bowel, the FIT test, which detects hidden blood, and tests for infections such as C. difficile and parasites.

Why it is done

Calprotectin helps distinguish inflammatory bowel disease from irritable bowel syndrome and monitors known inflammation. FIT is used to investigate bowel symptoms and in bowel screening programmes. Infection tests are used for diarrhoea that is persistent, bloody or follows travel or antibiotics.

How to prepare

There is usually no preparation; some tests ask you to avoid certain medicines or foods only if the laboratory instructs. You will be given a kit with a scoop and instructions to collect the sample without contaminating it with urine or toilet water.

What happens during the procedure

There is no procedure to attend for most stool tests — you collect the sample at home, seal and label the pot, and return it promptly as instructed. Blood and other tests can be arranged at the same time if your doctor wants a fuller picture.

Afterwards — recovery & results

Results usually take a few days to a week depending on the test. Your doctor will explain what the level means — for example a raised calprotectin usually leads to further bowel investigation, while a normal result makes active inflammation less likely.

Risks & considerations

These tests are risk-free to perform. Their limitation is accuracy: a single sample can miss intermittent problems, and some medicines (such as anti-inflammatory painkillers) can affect inflammation markers, so results are interpreted in context.

Frequently asked questions

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