IBD stands for Inflammatory bowel disease. The two most common type are Crohn’s Disease (CD) and Ulcerative Colitis (UC). CD can affect the entire gastrointestinal tract, whereas UC only affects the large intestine.
The cause is not known but it is thought to be associated with an autoimmune process. IBD is a chronic condition. When IBD is present, there can be periods when the disease is active, sometimes termed a ‘flareup’.
At other times, the disease is in remission and symptoms may be reduced or have subsided. In patients presenting with symptoms suggestive of IBS or IBD, NICE* recommends the use of faecal calprotectin analysis, as a first-line test, to rule out IBD. The test can avoid the need for IBS patients to undergo endoscopy procedures.
Calprotectin is a protein that is found in white blood cells called neutrophils. It provides different benefits to the body. These include providing antibacterial functions. When there is inflammation, these white blood cells release calprotectin.
When someone experiences lower gastrointestinal symptoms, a faecal calprotectin test can be used to identify if the symptoms are associated with an inflammatory bowel condition. It can be a useful marker to differentiate between IBD (Inflammatory Bowel Disease) and IBS (irritable bowel syndrome). When inflammation occurs, calprotectin is activated. The higher the degree of inflammation, the higher the concentration of calprotectin.
Those with diagnosed IBD, can perform faecal calprotectin tests to monitor ‘flare-ups’ and to evaluate severity of calprotectin levels. The test can be repeated several weeks later to monitor the levels to see if they are increasing or
decreasing if necessary. It can also be performed on IBD patients to help understand the effect prescribed medication is having on the disease, and adjust the prescription if necessary.
*NICE 2013 approved for IBD screening. Diagnostics guidance [DG11]
Faecal calprotectin testing is recommended by NICE as an option to help doctors distinguish between inflammatory bowel diseases, such as Crohn’s disease and ulcerative colitis, and noninflammatory bowel diseases, such as irritable bowel syndrome.
Adults & Children
No referral is required
A negative result is a calprotectin level of <50μg/g. A level below this range would suggest that your symptoms are unlikely to be caused by IBD. A borderline result is considered if the level of calprotectin is between 50-100μg/g. A calprotectin level of >100μg/g is considered positive.
If the test reports a borderline result with no explanation (such as taking certain medications), it is recommended that the test be repeated in 2-3 weeks to determine if the levels are decreasing or continuing to rise. If your test is positive, your GP may refer you to have a colonoscopy where biopsies are taken to confirm the diagnosis.