Leaky gut is clinically known as enterocutaneous fistula, the concept of which is the direct entry of intestinal contents into the free peritoneal cavity, resulting in acute diffuse peritonitis secondary to bacterial infection, manifested by abdominal pain, abdominal distension, and even chills and fever, and in severe cases, clinical symptoms of infectious shock can occur. The causes of intestinal fistulas generally include the following: 1) medical intestinal fistulas, mainly caused by poor tissue healing after intestinal resection for gastrointestinal tumors or benign diseases; 2) autoimmune diseases, such as ulcerative colitis and Crohn’s disease, which can cause intestinal contents to enter the free abdominal cavity through weak areas due to local intestinal tube weakness and increased intestinal pressure. The treatment of intestinal fistula is mainly conservative, that is, adequate drainage, and in severe cases, reoperation is required.