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Center for Systems Biomedicine


Inflammatory Bowel Diseases Program

Crohn's Disease (CD) Program

Inflammatory bowel disease affects approximately 1.4 million people in the US, mainly between age 15 and 30. The two major clinically defined forms of inflammatory bowel disease (IBD) are Crohn's disease (CD) and ulcerative colitis (UC). Crohn's disease generally involves the ileum and colon, but it can affect any region of the intestine, in a mostly discontinuous fashion. Ulcerative colitis involves the rectum and may affect part of the colon or the entire colon (pancolitis) in a continuous pattern. In CD the inflammation is often transmural, whereas in UC the inflammation is typically confined to the mucosa. CD can be associated with intestinal granulomas, strictures, and fistulas, but these are not typical findings in UC (Abraham C. & Cho J.H. NEJM 2009;361:2066-78). Symptoms can vary and include abdominal pain, nause and diarrhea which can be accompanied by hemorrhage. The precise etiology of Crohn's disease and ulcerative colitis is not presently known. The current working hypothesis is of deregulated mucosal immune responses to commensal gut flora in genetically susceptible individuals (Xavier R.J. and Podolsky D.K. Nature 2007;448:427-34). The discordance of IBD among monozygotic twins and the development of IBD in immigrants to high prevalence countries and in countries undergoing rapid Westernization also highlights the importance of environmental factors in disease pathogenesis (Kaser A. et al. Annu. Rev. Immunol. 2010;28:573-621). Cigarette smoking affects these two diseases differently: smokers are at increased risk for Crohn's disease and tend to have more severe disease, whereas former smokers and nonsmokers are at greater risk for ulcerative colitis. Several recent studies have attempted to document the epidemiological overlap between IBD and various auto-immune diseases (Bernstein C.N. et al. Gastroenterology 2005;129:827-36, Cohen R. et al. Inflamm Bowel Dis 2008;14:738-43, Gupta G. et al. Gastroenterology 2005;129:819-26, Weng X. et al. Am J Gastroenterol 2007;102:1429-35). These studies point to an increased prevalence of ankylosing spondylitis, psoriasis, asthma, atopic dermatitis, multiple sclerosis (MS) and possibly rheumatoid arthritis (RA), in patients with IBD (Lees C.W. et al. Gut 2011; 60:1739-53). In Crohn's, surgery is not a cure. Recurrence of the disease can be quite high. Treatment of the disease focuses in relieving the symptoms and the inflammation. 

Pediatric IBD Program

Information coming soon! 

Ulcerative Colitis Program

Information coming soon!






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