Faecal leukocyte esterase activity is an alternative biomarker in inflammatory bowel disease.

Background: Leukocyte cytosolic proteins (e.g., calprotectin) are emerging biomarkers for inflammatory bowel disease.

Proteolysis is a confounding factor in the interpretation of faecal calprotectin.

Background: Calprotectin is a 36 kDa calcium and zinc binding protein. An increased level of calprotectin points towards inflammatory bowel disease. However, the biomarker calprotectin shows 14 potential cleavages sites for trypsin.