Calprotectin (feces)

General Information

Fecal calprotectin is a calcium and zinc binding protein. 60% of it is found in the cytosol of neutrophils. less - in monocytes and macrophages. Certain amounts of calprotectin are found in blood plasma, urine, cerebrospinal fluid, feces, saliva, and synovial fluid. Calprotectin is involved in a number of physiological processes, including: cell differentiation, immune regulation, tumor apoptosis, and inflammatory processes. It is a positive protein of the acute inflammatory process. It initiates the expression of cell receptors involved in neutrophil migration, adhesion and phagocytosis. Thus, it participates in the immune response as an injury-associated protein.
The detection of calprotectin in feces indicates the migration of neutrophils into the gastrointestinal tract as a result of the inflammatory process. Fecal calprotectin is directly related to gastrointestinal inflammatory processes and is considered a marker of inflammatory processes in the gastrointestinal tract.
Some pathogens cause infectious or inflammatory processes in the intestinal mucosa, followed by an increase in its permeability and the migration of granulocytes and monocytes towards the intestine. In addition, the bacterial flora in the intestinal lumen stimulates the release of calprotectin and similar mediators from granulocytes and monocytes, which increases the concentration of calprotectin in the intestinal lumen.
Fecal calprotectin is a highly sensitive biomarker for differentiating pathologies such as inflammatory bowel disease and irritable bowel syndrome. It is actively used for monitoring the course of inflammatory bowel diseases, relapses and remissions, and postoperative evaluation.
Fecal calprotectin is highly resistant to both pancreatic and intestinal proteases (enzymes) and bacterial degradation. Due to its high specificity, compared to serum calprotectin, determination of fecal calprotectin is preferred in the diagnostics of inflammatory diseases of the gastrointestinal tract. It is one of the main determining factors for differentiating intestinal organic (inflammatory disease) and functional (irritable bowel syndrome) pathologies, whose symptoms and clinical picture are often practically identical.
Despite the high sensitivity, calprotectin is not a specific marker of inflammatory diseases of the gastrointestinal tract, as it is also detected during malignant processes, polyposis, the effect of anti-inflammatory non-steroids and others.