Clinical significance
Calprotectin is a calcium-binding protein found in neutrophils and, to a lesser extent, in monocytes. Its presence in stools can be used as an indirect marker of neutrophil infiltration of the bowel wall, and therefore of bowel inflammation. Raised calprotectin levels are found in chronic inflammatory bowel disease (Crohn’s disease, ulcerative colitis), some bowel cancers, diverticulitis and acute enteritis. It can be used to distinguish functional bowel disorders (irritable bowel syndrome), in which faecal calprotectin is not raised, from chronic inflammatory diseases (IBD, inflammatory bowel disease).
Clinical indications
To distinguish between inflammatory bowel disease (IBD) and irritable bowel syndrome; to monitor and follow up the treatment of bowel inflammation. Bowel cancer, diverticulitis, peptic disorders.
Sample type
Stools
Preparation
The stool must be passed naturally, without suppositories and/or laxatives. In the week before collection, stop taking antidiarrhoeals, charcoal and bismuth.
Notes
Values between 40 and 60 micrograms indicate possible bowel inflammation; it is advisable to repeat the test to confirm. Values above 60 micrograms indicate significant inflammation of the bowel lining.