The normal value of fecal calreticulin is 0 to 50, and a fecal calreticulin test of 1000 is a more serious condition. Fecal calprotectin is a calcium and zinc binding cytoplasmic protein, mainly released by intestinal neutrophils and macrophages, with anti-bacterial degradation, not easily broken down by bacteria in the intestinal tract, thus truly reflecting the severity of inflammation in the intestinal tract. Fecal calprotectin is generally used to identify inflammatory bowel disease and functional bowel disease. Functional bowel disease usually has intestinal symptoms but no source of infection, such as bacteria or viruses, so fecal calprotectin will not be elevated. In contrast, inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease have an inflammatory infiltrate that causes elevated fecal calprotectin. When fecal calprotectin is elevated, suggesting that there is an inflammatory response in the intestinal tract, it is recommended that timely medical treatment be sought, and enteroscopy and other tests can be chosen to exclude organic lesions, and targeted treatment can be carried out after the cause is clearly identified.