blood transfusions pancolitis and toxic megacolon patients with ulcerative colitis limited to the rectum (proctitis) or colitis limited to the end of the left colon (proctosigmoiditis) usually do quite well. brief periodic treatments using oral medications or enemas may be sufficient. serious complications are rare in these patients. in those with more extensive disease blood loss from the inflamed intestines can lead to anemia and may require treatment with iron supplements or even blood transfusions. rarely the colon can acutely dilate to a large size when the inflammation becomes very severe. this condition is called toxic megacolon. patients with toxic megacolon are extremely ill with fever abdominal pain and distention dehydration and malnutrition. unless the patient improves rapidly with medication surgery usually is necessary to prevent colon rupture. in a published scandinavian cohort study of over 500 patients with ulcerative colitis followed for up to 10 years after diagnosis it was found that their mortality rate did not differ from the general population. also the cumulative colectomy rate after 10 years was 9. 8% nearly 50% of the patients were relapse free in the last five years of the study and only 20% of the patients with proctitis or left-sided disease progressed to pancolitis. cancers colon cancer is a recognized complication of chronic ulcerative colitis. the risk for cancer begins to rise after eight to ten years of colitis. patients with only ulcerative proctitis probably do not have increased risk of colon cancer compared to the general population. among patients with active pancolitis (involving the entire colon) for 10 years or longer the risk of colon cancer is increased compared to the general population. in patients with colitis limited to the left side of the colon the risk of colon cancer is increased but not as high as in patients with chronic pancolitis. the current estimates for the cumulative incidence of colon cancer associated with ulcerative colitis are 2. 5% at 10 years 7. 6% at 30 years and 10. 8% at 50 years. patients at higher risk of cancer are patients with positive family histories of colon cancer long durations of colitis extensive colon involvement and primary sclerosing cholangitis (psc) another complication of ulcerative colitis. since these cancers have a more favorable outcome when diagnosed and treated at an earlier stage yearly colon examinations may be recommended after eight years of known extensive disease. during these examinations samples of tissue (biopsies) can be taken to search for precancerous changes in the lining cells of the colon. when precancerous changes are found removal of the colon may be necessary to prevent colon cancer. other complications of ulcerative colitis complications of ulcerative colitis can involve other parts of the body. ten percent of the patients can develop inflammation of the joints (arthritis). some patients have low back pain due to arthritis of the sacroiliac joints. ankylosing spondylitis (as) is a type of arthritis that affects the vertebral joints of affected individuals. there seems to be an increased incidence of ankylosing spondylitis among patients with inflammatory bowel disease. rarely patients may develop painful red skin nodules (erythema nodosum). others can have painful red eyes (uveitis episcleritis). because these particular complications can risk permanent vision impairment eye pain or redness are symptoms that require a physician's evaluation. diseases of the liver and bile ducts may also be associated with ulcerative colitis. for example in patients with a rare condition called sclerosing cholangitis repeated infections and inflammation in the bile ducts can lead to recurrent fever yellowing of skin (jaundice) cirrhosis and the need for a liver transplant. finally patients with ulcerative colitis also might have an increased tendency to form blood clots especially in the setting of active disease.
what are the complications of ulcerative colitis?