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If you develop diarrhoea with bleeding, abdominal pain, or weight loss lasting for several weeks or longer, your doctor may suspect that you have Inflammatory Bowel Disease, particularly if you are a young adult or have a family history of IBD.  You will then need tests and physical examinations to confirm a diagnosis.  These may include:

Blood Tests and Stool Tests

Simple blood tests can show whether you have inflammation somewhere in your body and whether you are anaemic. Your stools can also be tested for signs of bleeding or inflammation, and to check whether your diarrhoea is caused by an infection. If inflammation is confirmed, you may then have an examination to look inside your body, such as an endoscopy, x-ray or scan.

Endoscopies

There are several types of endoscopy which can have different names according to the type of scope used and the part of the gut being examined. For example:

• An upper GI endoscopy – If you have symptoms coming from the upper part of your gut, you may have what is known as an upper GI (Gastrointestinal Tract) endoscopy or gastroscopy. In this, the doctor or specialist endoscopist inserts an endoscope (a thin flexible tube with a camera in its tip) through your mouth so they can examine your oesophagus, stomach and duodenum.

• A sigmoidoscopy or colonoscopy – If you have symptoms in your ileum or colon, you will have a sigmoidoscopy or a colonoscopy. This means a sigmoidoscope (a short endoscope) or a colonoscope (a longer and more flexible endoscope) will be inserted through the anus (back passage) to examine the rectum and colon.

Endoscopies like these should not be painful but may be uncomfortable, so you may be given a sedative (medication that has a calming effect) to help you relax. Biopsies (small samples of tissue) are often taken during the endoscopy. These can then be examined under a microscope to confirm the diagnosis.

Capsule Endoscopy

For a capsule endoscopy you will be asked to swallow a capsule about the size of a small grape, containing a tiny camera, transmitter and light source. As it passes through your system it takes photos of the inside of the gut and transmits these to a data recorder worn around the waist. The capsule is disposable and passes out of the body naturally in a bowel movement. Not all centres offer capsule endoscopy and it may not be suitable for everyone, for example if you have a stricture.

Barium X-ray Tests

Barium sulphate is a harmless white chalky substance which can be used to coat the lining of the gut and so give a clearer outline in an x-ray. It can be given as a drink to help show up problems in the stomach or small intestine, or in an enema to show up inflammation in the colon.

MRI and CT Scans

Other tests that are increasingly used to look at the location and extent of the inflammation include MRI (Magnetic Resonance Imaging) and CT (Computerised Tomography) scans. MRI scans use magnets and radio waves, and CT scans use a special kind of x-ray to build up a ‘3D’ image of the body. Some centres also use ultrasound.

© Crohn’s and Colitis UK 2015