Understanding Calprotectin – Information for Patients
Why has my doctor requested a faecal calprotectin test?
The #1 Resource for Calprotectin in the UK and Eire
Why has my doctor requested a faecal calprotectin test?
Measuring faecal calprotectin levels can help doctors diagnose and monitor conditions such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and other gastrointestinal disorders. Patients can benefit from understanding the importance of calprotectin testing as it can potentially affect their health and quality of life. By monitoring calprotectin levels over time, healthcare providers can monitor the effectiveness of treatment and adjust treatment plans accordingly. Patients can be confident that understanding the calprotectin test can potentially help improve their health and prevent unnecessary procedures. Remember to always see your healthcare provider and follow their recommendations for testing and treatment.
In the blood, red cells perform the vital role of delivering oxygen and removing carbon dioxide from around the body by virtue of the haemoglobin they contain. The role of white cells is to help defend the body against infection and foreign substances. Calprotectin is a protein that is found in white blood cells and it has strong antibacterial and antifungal properties. There is as much calprotectin in the white cells that carry it, as there is haemoglobin in red cells.
Calprotectin is activated when inflammation occurs (whatever the cause of that may be) and thus can be used as a diagnostic indicator. The concentration of calprotectin relates directly to the severity of the inflammation. Figure 1. represents the calprotectin concentrations measured in faecal samples from patients diagnosed with Crohn’s Disease and shows increasing levels with progression of the condition.
Thus, when lower abdominal symptoms exist, a faecal calprotectin test is used to identify whether an inflammatory bowel condition that requires further investigation, is the possible cause.
Figure 1: Faecal calprotectin levels plotted against Crohn’s disease activity (Dr James Turvill, Frontline Gastroenterology 2014)
Inflammatory bowel disease is a group of inflammatory conditions of the colon and small intestine. The major types of IBD are Crohn’s disease and Ulcerative Colitis.
Irritable bowel syndrome is a common condition of the digestive system. It can often cause bouts of stomach cramps, bloating, diarrhoea and constipation.
Faecal calprotectin has proven to be an extremely useful and cost effective marker to help differentiate between IBD (Inflammatory Bowel Disease) and IBS (Irritable Bowel Syndrome). The test gained approval from NICE at the end of 2013 for screening purposes and since then the volume of calprotectin testing has increased dramatically. The calprotectin result helps doctors determine the next course of action in diagnosis and treatment of bowel conditions. It has no doubt saved many patients from unnecessary colonoscopies and helped in the diagnosis and subsequent treatment of those with some form of inflammatory bowel disease (IBD) e.g. Crohn’s Disease (CD) or Ulcerative Colitis (UC).
Faecal calprotectin testing is an extremely useful tool for the clinical team to help build up a picture of what might be causing symptoms, however it is not a specific indicator of anything other than the fact that inflammation is present somewhere in the digestive system (mouth to anus!). The challenge for the clinical team it to determine where that is coming from, and if it is significant.
In the UK, many hospitals are using the York Care Pathway, which is endorsed by BSG, NICE and Crohn’s & Colitis, for interpretation of the values obtained from a faecal calprotectin test with the following criteria:
As you can see it isn’t a clear cut yes/no result – there is an intermediate range that isn’t positive, but it is higher than a negative result should be, so other factors need to be taken into consideration.
Calprotectin levels in children tend to be higher than those in adults, especially in the first few months: Davidson et al 2017 Annuals of Clinical Biochemistry
Most guidance suggests that adult cut-offs values are applicable from 4 years onwards.
Bacterial infections can cause transient rises in calprotectin levels; viral infections, don’t tend to cause significant increases: Chen et al 2012
Other publications have reported significantly lower calprotectin levels even for bacterial infections, so the calprotectin level is probably also related to the specific causative agent (some bacteria are more pathogenic than others), the severity of the disease and the age of the patient (the study above was paediatric who can have higher levels anyway).
Things that cause an irritation of the gastric system and hence an inflammatory response will cause the calprotectin levels to rise:
Proton pump inhibitors have been associated with higher calprotectin levels: Poullis et al 2003 Correspondence European J Gastro & Hept.
In the literature there are also a number of other conditions that may (or may not) cause the calprotectin levels to rise e.g. untreated allergies or coeliac disease, pancreatitis, appendicitis, mild diverticulitis, ankylosing spondylitis. Studies differ in their conclusions, but the levels are also not usually as high as that seen with IBD.
Seek further advice from your healthcare professional
Evidence-based travel advice for individuals with Crohn’s disease or ulcerative colitis:
IBD Passport is an award winning website that aims to provide comprehensive, practical and reliable information on all aspects of travelling with Crohn’s Disease or Ulcerative Colitis making planning a trip easy.
IBD Passport is a UK registered non-profit charity (Registered number: 1171268) with a global reach aimed to support IBD travelers of all nations and regions in the world.
Crohn’s and Colitis Companion gives advice on wide variety of subjects to IBD patients including:
Living with Crohn’s Disease – read the blog from a patient who believes self testing of his faecal calprotectin levels will help better manage his disease.
The products on this site are not suitable for personal purchase and self-testing without direction from a doctor. If you have any concerns about Calprotectin testing or IBD, IBS and related conditions, please speak to your GP.
Visit the New Patient Zone for More Information