Useful For/Utility

The Calprotectin assay is an in vitro diagnostic chemiluminescent immunoassay intended for the quantitative measurement, in human stool, of fecal calprotectin, a neutrophilic protein that is a marker of mucosal inflammation. Calprotectin is a heterocomplex composed of the calcium and zinc binding proteins S100A8 and S100A9. It constitutes more than 60% of total protein in the cytosol of neutrophils, which infiltrate the intestinal mucosa as part of the inflammatory response. Consequently, organic diseases of the bowel result in elevated levels of fecal calprotectin. The concentration of calprotectin in stool reflects the number of neutrophils present and provides an indicator of the severity of intestinal inflammation

The Calprotectin assay can be used as an aid in the diagnosis and management of inflammatory bowel diseases (IBD), specifically Crohn’s disease and ulcerative colitis, and as an aid in differentiation of IBD from irritable bowel syndrome (IBS). Test results are to be used in conjunction with information obtained from the patients’ clinical evaluation and other diagnostic procedures.

Patient symptoms include chronic or recurrent episodes of abdominal pain and diarrhea. The clinical manifestations of IBD are not specific and symptoms are similar to other non-organic diseases such as irritable bowel syndrome (IBS), requiring endoscopy to confirm diagnosis. The non-invasive measurement of fecal calprotectin is considered a useful screening tool for differentiating IBD from IBS.

Other intestinal diseases, including many gastrointestinal infections and colorectal cancer, can result in elevated levels of calprotectin. Therefore, a diagnosis of active IBD should be made only in the context of other diagnostic testing and the total clinical status of the patient. Fecal calprotectin is an indicator of neutrophilic presence in the stool and is not specific for IBD.