Calprotectin becomes available in the intestinal lumen via leukocyte shedding, active secretion, cell disturbance and cell death. This results in elevated faecal calprotectin levels, which can be detected in the stool. Elevated faecal calprotectin levels therefore indicate intestinal inflammation. People with active inflammatory bowel diseases (IBDs) such as, ulcerative colitis or Crohn's disease have as much as a 10-fold increase in faecal calprotectin levels and the measurement of calprotectin can serve as a biochemical test for these diseases.