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What is a faecal immunochemical test?

The faecal immunochemical test detects small amounts of blood in your faeces, which you would not normally see or be aware of. Faeces are sometimes called stools or motions. It is the waste that you pass out from your back passage (anus).

Why is the faecal immunochemical test done?

There are several disorders which may cause bleeding into the gut (intestine) - for example, gastric أو duodenal ulcers, التهاب القولون التقرحي, bowel polyps و bowel (colorectal) cancer.

Any heavy bleeding into your gut would be obvious because your stools (faeces) would be bloody or a very black colour. However, sometimes there is only a trickle of blood. If you only have a small amount of blood in your stools then the stools look normal. However, the faecal immunochemical test will detect the blood. So, the test may be done if you have abdominal symptoms (tummy) such as persistent pain. It may also be done to screen for bowel cancer before any symptoms develop (see below).

ملاحظة: the faecal immunochemical test can only say that you are bleeding from somewhere in the gut. It cannot tell from which part. If the test is positive then further tests will be arranged to find the source of the bleeding - usually, endoscopy و/أو colonoscopy.

How is the faecal immunochemical test done?

A small sample of stool (faeces) is smeared on to a piece of card. You can obtain the stool sample from stool passed on to layers of toilet paper, into a clean disposable container, or on to a clean disposable glove. It is very important that the stool sample has not come into contact with the water in the toilet. The sample is then sent to a laboratory for testing.

If your test is part of the bowel screening programme, you will be sent a test kit with clear instructions and an envelope to send the sample (within a special test tube) to a laboratory for testing.

Usually faecal immunochemical tests are done on one stool sample. For the faecal immunochemical test, there are no dietary, drug, or dental procedure restrictions.

Screening for bowel cancer

Screening means looking for early signs of a particular disease in otherwise healthy people who do not have any symptoms and when treatment is likely to be curative. Bowel (colorectal) cancer screening aims to detect colorectal cancer at an early stage when there is a good chance that treatment will cure the cancer.

As colorectal cancer is much more common in older people, the decision has been made for people of a certain age to be invited to participate in the colorectal cancer screening programme. This involves testing three samples of your stools (faeces) for blood. The NHS Bowel Cancer Screening Programme has been introduced in the UK as follows:

• In England, Wales and Northern Ireland, people aged 60-74 are routinely offered screening every two years.

• In Scotland, people aged 50-74 are routinely offered screening every two years.

The first test kit should automatically arrive by post within a few weeks after you reach the age at which screening starts. After your first screening test, you will then be sent another invitation and screening kit every two years until you reach the maximum age.

See the separate leaflet called Screening for Bowel (Colorectal) Cancer.