Which of the following statement is false: March 2007

Ans. C: Stricture involving the colon is found in ulcerative colitisCrohn's disease/regional enteritis) is an autoimmune disease, which can affect any pa of the gastrointestinal tract from mouth to anus (terminal ileum is the area most commonly affected).Anal lesions are also commonThe disease is characterized by areas of inflammation with areas of normal lining between in a symptom known as skip lesions.Microscopy of Crohn's disease show focal areas of chronic inflammation involving all layers of the intestinal walls.There are non-caseating granulomas, but these are found in only 60% of patients.The main gastrointestinal symptoms are:Abdominal pain may be the initial symptom of Crohn's disease. It is often accompanied by diarrhea, especially in those who have had surgery. The diarrhea may or may not be bloody.The nature of the diarrhea in Crohn's disease depends on the pa of the small intestine or colon that is involved. Ileitis typically results in large-volume watery feces. Colitis may result in a smaller volume of feces of higher frequency.Visible bleeding in the feces is less common in Crohn's disease than in ulcerative colitis, but may be seen in the setting of Crohn's colitis.Although the association is greater in the context of ulcerative colitis, Crohn's disease may also be associated with primary sclerosing cholangitisPerianal discomfo may also be prominent in Crohn's disease. Itchiness or pain around the anus may be suggestive of inflammation, fistulization or abscess around the anal area or anal fissure.Crohn's disease is associated with a type of rheumatologic disease known as seronegative spondyloahropathy. This group of diseases is characterized by inflammation of one or more joints (ahritis) or muscle inseions (enthesitis). Common complications of inflammation include scarring that can produce intestinal blockage (obstruction) and deep ulcers penetrating through the bowel wall that can create pus-filled pockets of infection (abscesses) or abnormal connecting channels between the intestine and other organs (fistulas).When the large intestine is affected extensively by Crohn's disease, rectal bleeding commonly occurs.After many years, the risk of colon cancer (cancer of the large intestine) is greatly increased.About one third of people who develop Crohn's disease have problems around the anus, especially fistulas and cracks (fissures) in the lining of the mucus membrane of the anus.Crohn's disease may lead to complications in other pas of the body. These complications include gallstones, inadequate absorption of nutrients, urinary tract infections, kidney stones, and deposits of the protein amyloid in several organs (amyloidosis).A colonoscopy is the best test for making the diagnosis of Crohn's disease as it allows direct visualization of the colon and the terminal ileum, identifying the pattern of disease involvement. Finding a patchy distribution of disease, with involvement of the colon or ileum but not the rectum, is suggestive of Crohn's disease, as are other endoscopic stigmata. The most common disease that mimics the symptoms of Crohn's disease is ulcerative colitis, as both are inflammatory bowel diseases that can affect the colon with similar symptoms.It is impoant to differentiate these diseases, since the course of the diseases and treatments may be different.