Calprotectin, Fecal

Calprotectin, Fecal (stool calprotectin) is used in the evaluation of suspected inflammatory bowel disease and to help separate inflammatory causes of gastrointestinal symptoms from noninflammatory conditions, including irritable bowel syndrome and other explanations for abdominal complaints or gastrointestinal bleeding. In patients with known inflammatory bowel disease, fecal calprotectin supports assessment of disease activity and can be used to monitor response to therapy over time.

Fecal calprotectin reflects the movement of neutrophils into the gut lumen and functions as a noninvasive indicator of intestinal mucosal inflammation. Concentrations increase in inflammatory bowel diseases such as ulcerative colitis and Crohn disease and generally parallel the degree of inflammatory activity, whereas values are usually within reference limits in functional conditions like irritable bowel syndrome. The assay is not disease-specific; elevations may occur with diverse inflammatory disorders of the gastrointestinal tract. Interpretation therefore requires integration with symptoms, endoscopic findings, histology, and other laboratory data. Inflammatory bowel diseases arise from dysregulated immune interactions between the host and the microbiome and are associated with increased complication risk; management follows a stepwise approach aimed at controlling inflammation and achieving mucosal healing.