Ulcerative colitis is a disease of unknown origin that occurs in the mucosa of the large intestine and is characterized by bleeding ulcers. Ulcerative colitis is a disease that is highly prevalent in developed countries such as Europe and the United States. However, the incidence has increased rapidly in recent years in China. The main clinical manifestations include bloody mucus stools, abdominal pain, diarrhea, and shortness of breath. Ulcerative colon can have serious complications such as cancer, intestinal perforation and, more seriously, biliary cirrhosis and arthritis. Clinical manifestations: Most of the disease starts slowly, the disease is more stubborn, and the symptoms often persist or have a chronic course with intermittent episodes and remission periods. Eventually, it may cause wasting, anemia, general debility and dystrophic edema. Diarrhea is the main symptom of the disease, and in severe cases, the stool can be more than 10 times a day. Stool examination often contains blood, pus and mucus. During defecation, there may be urgent and then heavy and paroxysmal abdominal pain, which may be relieved or disappear after defecation. Mental stimulation, nervousness, exertion and eating disorders are often triggers for the onset of symptoms. Some patients may have chills and fever, anorexia and nausea, abdominal pressure pain or lumps, and increased peripheral blood leukocytes. In addition to toxemia, patients may also have anemia, decreased plasma protein, water and electrolyte disorders and acid-base imbalance in the later stages. The rapid onset of the disease accounts for about 5% of patients, with rapid development, severe systemic toxic symptoms, frequent complications and high mortality. The rest of the patients who are in remission after treatment enter the chronic process. In chronic cases, there is also the possibility of sudden exacerbation of the disease. The difference in severity is an important feature of the disease.