At the inner surface of the colon, corresponding to the transverse groove between the colonic pouches, the circular muscle thickens and the intestinal mucosa folds into a colonic semilunar fold. The disappearance of the colonic pouch is the result of paralysis of the mucosal muscle layer. Early X-rays of ulcerative colitis show the disappearance of the colonic pouch. What are the symptoms that are easily confused with it? 1, irritable bowel syndrome The onset of the disease is related to mental and psychological disorders, often abdominal pain, bloating, abdominal tinnitus, may appear alternating constipation and diarrhea, accompanied by symptoms of generalized neurosis. There is mucus but no pus and blood in the stool, a few white blood cells are occasionally seen on microscopic examination, and there is no organic lesion on colonoscopy and other examinations. 2.Colorectal cancer Most often seen in middle-aged people, rectal cancer finger examination often palpable masses, fecal occult blood test is often positive. Colonoscopy and barium enema examination are valuable for differential diagnosis, but must be distinguished from ulcerative colitis carcinoma. 3, amoebic enteritis lesions often involve both ends of the large intestine, namely the rectum, sigmoid colon and cecum, ascending colon. The ulcer is usually deep, the edge is submerged, the mucosa between the ulcer and the ulcer is mostly normal, fecal examination can find lyso-amoebic trophozoites or encapsulation, through colonoscopy to take the ulcer surface exudate or ulcer edge tissue to find amoeba, the positive rate is high; anti-amoebic treatment is effective. 4, schistosomiasis History of exposure to schistosomal epidemic water, often with hepatosplenomegaly, chronic phase of the rectum can have granuloma-like hyperplasia, may have a malignant tendency; stool examination can be found schistosome eggs, hatching trichurias positive results. Proctoscopy in the acute stage can be seen in the mucosa with yellow-brown particles, biopsy mucosal pressure or histopathological examination can be found schistosome eggs. 5, chronic bacterial dysentery Generally have a history of acute dysentery, repeated fresh stool culture can isolate Bacillus dysenteriae, antibiotic treatment is effective. 6, ischemic colitis Most commonly seen in the elderly, caused by arteriosclerosis, sudden onset, lower abdominal pain with vomiting, bloody diarrhea, fever, increased white blood cells 24-48h later. In mild cases, the process is reversible and can be cured after l-2 weeks to 1-6 months; in severe cases, intestinal necrosis, perforation and peritonitis occur. During the barium enema X-ray examination, finger indentation sign, pseudotumor, jagged changes of intestinal wall and fusiform stenosis of intestinal canal are seen. Endoscopically, dark purple elevation caused by submucosal hemorrhage, peeling bleeding and ulceration of the mucosa can be seen, which is clearly demarcated from the normal mucosa. The lesions were mostly in the splenic flexure of the colon.