Ulcerative colitis, referred to as ulcerative colitis, is a chronic non-specific inflammatory disease that affects the mucosa of the colon, often starting in the left hemocolon and progressing to the proximal colon and even the whole colon in a continuous manner. The clinical symptoms vary in severity and may alternate between remission and attack, and at the beginning of the disease, it only shows an increase in the number of bowel movements, but in severe cases, there are 10-30 bowel movements per day, and the stool is often mixed with pus and mucus, usually a small amount of blood in the stool, but in severe cases, there may be a large amount of blood in the stool or bloody water-like stool. The abdominal pain is mostly confined to the lower abdomen, and in mild cases, there may be no abdominal pain. Ulcerative colitis can develop at any age, but it is most common in patients younger than 30 years of age, with a peak incidence at 10-20 years of age and a second peak at 65-70 years of age. The disease is often confused with Crohn’s disease, colon cancer, amoebic dysentery, and ischemic colitis. Accurate diagnosis often requires fiberoptic colonoscopy, which can directly observe changes in the colonic mucosa, determine the basic features and extent of the lesion, and perform biopsies, which can greatly improve the diagnostic accuracy of ulcerative colitis. In addition to recurrent diarrhea, blood in the stool and other symptoms that seriously affect daily life, ulcerative colitis is also prone to many complications: 1. toxic megacolon, a serious complication, prone to intestinal necrosis and perforation, with a very high mortality rate of 30% to 50%; 2. colon perforation, mostly based on toxic megacolon dilatation; 3. lower gastrointestinal bleeding, rectal and colonic can be widely oozing blood. The vast majority of cases are bloody stools and pus-blood stools. Sometimes a few cases (about 4%) can have repeated lower gastrointestinal bleeding, and the amount of bleeding can reach thousands of milliliters, and even shock, which requires emergency surgery; 4. The incidence of rectal and colon cancer is 0.7% to 8%, or even up to 13%, which is 5 to 20 times higher than the general population. The incidence of cancer is significantly higher in those with a disease duration of more than 10 years, extensive lesions in the whole colon, as well as in adolescents and children. Cancer can occur in any part of the whole colon, and 5% to 42% are multicentric cancers. For the treatment of ulcerative colitis, the American Gastroenterological Association classified it in 2000 and established treatment guidelines: mild to moderate cases are generally treated with maintenance aminosalicylates, including diet modification, antidiarrheal drugs, and intestinal probiotics; moderate to severe cases show symptoms of systemic toxicity, with stools more than four times a day, often with bloody stools, frequent stools, and abdominal pain, etc. At this stage, it is usually necessary to apply corticosteroids Immunomodulatory drugs such as corticosteroids, anti-tumor necrosis factor-a drugs, and if necessary, parenteral nutrition; for severe ulcerative colitis, that is, the number of stools more than 6 times a day, accompanied by abdominal pain, cramps, toxic fever, anemia and other serious conditions need to be surgical treatment, including total colectomy, ileostomy, IPAA (total colectomy, ileal pouch-anal anastomosis) surgery and many other surgical methods The procedure includes total colectomy, ileostomy, IPAA (total colectomy, ileal pouch-anal tube anastomosis) and many other surgical procedures.