Calprotectin as a diagnostic tool for inflammatory bowel diseases.

Inflammatory bowel diseases (IBD) are chronic intestinal disorders caused by a number of factors, including external influences, intestinal microbiota and genetics. The two major clinically defined types of IBD are Crohn's disease and ulcerative colitis, each of which is characterized by relapses in the clinical course, thus patients must be under constant observation via regular endoscopies. As endoscopy, which has been used for direct evaluation and diagnosis of IBD, requires uncomfortable and expensive bowel preparation, a non-invasive test was required to reduce the number of patients undergoing unnecessary endoscopy. Calprotectin is a protein occurring in the cytosol of inflammatory cells and is released by the activation of leukocytes. As it is elevated and stable in the faeces of patients with IBD and can be reliably detected in faecal samples of <5 g, it may serve as an inexpensive, non-invasive diagnostic method for IBD. This is explored in the following review.