nature publishing group 501© 2010 by the American College of Gastroenterology The American Journal of GASTROENTEROLOGY ACG PRACTICE GUIDELINES INTRODUCTION Ulcerative colitis (UC) is a chronic disease characterized by diff use mucosal infl ammation limited to the colon. It involves the rectum in about 95 % of cases and may extend proximally in a symmetri-cal, circumferential, and uninterrupted pattern to involve parts or all of the large intestine. Th e hallmark clinical symptom is bloody diarrhea oft en with prominent symptoms of rectal urgency and ten-esmus. Th e clinical course is marked by exacerbations and remis-sions, which may occur spontaneously or in response to treatment changes or intercurrent illnesses ( 1,2 ). UC aff ects approximately 500,000 individuals in the United States with an incidence of 8 – 12 per 100,000 population per year; the incidence has remained rela-tively constant over the last fi ve decades ( 3 – 8 ). Th e disease accounts for a quarter million physician visits annually, 30,000 hospitalizations, and loss of over a million workdays per year ( 9 ). Th e direct medical costs alone exceed four billion dollars annually, comprising estimated hospital costs of over US $ 960 million ( 10,11 ) and drug costs of $ 680 million ( 11 ). RECOMMENDATIONS FOR DIAGNOSIS AND ASSESSMENT In a patient presenting with persistent bloody diarrhea, rectal urgency, or tenesmus, stool examinations and sigmoidoscopy or colonoscopy and biopsy should be performed to confi rm the presence of colitis and to exclude the presence of infectious and noninfectious etiologies. Characteristic endoscopic and histologic fi ndings with negative evaluation for infectious causes will suggest the diagnosis of UC. Ulcerative Colitis Practice Guidelines in Adults: American College of Gastroenterology, Practice Parameters Committee Asher Kornbluth , MD 1 , D a v i d B . S a c h a r , M D , M A C G 1 a n d Th e Practice Parameters Committee of the American College of Gastroenterology Guidelines for clinical practice are aimed to indicate preferred approaches to medical problems as established by scientifi cally valid research. Double-blind placebo controlled studies are preferable, but compassionate-use reports and expert review articles are used in a thorough review of the literature conducted through Medline with the National Library of Medicine. When only data that will not withstand objective scrutiny are available, a recommendation is identifi ed as a consensus of experts. Guidelines are applicable to all physicians who address the subject regardless of specialty training or interests and are aimed to indicate the preferable but not necessarily the only acceptable approach to a specifi c problem. Guidelines are intended to be fl exible and must be distinguished from standards of care, which are infl exible and rarely violated. Given the wide range of specifi cs in any health-care problem, the physician must always choose the course best suited to the individual patient and the variables in existence at the moment of decision. Guidelines are developed under the auspices of the American College of Gastroenterology and its Practice Parameters Committee and approved by the board of trustees. Each has been intensely reviewed and revised by the Committee, other experts in the fi eld, physicians who will use them, and specialists in the science of decision analysis. The recommendations of each guideline are therefore considered valid at the time of composition based on the data available. New developments in medical research and practice pertinent to each guideline will be reviewed at a time established and indicated at publication to assure continued validity. The recommendations made are based on the level of evidence found. Grade A recommendations imply that there is consistent level 1 evidence (randomized controlled trials), grade B indicates that the evidence would be level 2 or 3, which are cohort studies or case – control studies. Grade C recommendations are based on level 4 studies, meaning case series or poor-quality cohort studies, and grade D recommendations are based on level 5 evidence, meaning expert opinion. Am J Gastroenterol 2010; 105:501–523; doi: 10.1038/ajg.2009.727; published online 12 January 2010 1 Dr. Henry D. Janowitz Division of Gastroenterology, Samuel Bronfman Department of Medicine, Mount Sinai School of Medicine , New York , New York , USA . Correspondence: Asher Kornbluth, MD , The Dr. Henry D. Janowitz Division of Gastroenterology, Samuel Bronfman Department of Medicine, Mount Sinai Medical Center , 1751 York Avenue, New York , New York 10128 , USA . E-mail: [email protected] Received 2 February 2009; accepted 19 February 2009 CMEThe American Journal of GASTROENTEROLOGY VOLUME 105 | MARCH 2010 www.amjgastro.com502 Kornbluth and Sachar Th e diagnosis of UC is suspected on clinical grounds and supported by the appropriate fi ndings on proctosigmoidoscopy or colonoscopy, biopsy, and by negative stool examination for infectious causes ( 12 ). Inquiries should be made regarding factors that may potentially exacerbate symptoms of UC; e.g., smoking cessation or nonsteroidal anti-infl ammatory drug use or possibly isotretinoin ( 13 – 16 ). Infections can also pro-duce clinical fi ndings indistinguishable from idiopathic UC, so microbiologic studies for bacterial infection (including specifi c assays for Escherichia coli 0157:H7) and parasitic infestation, as well as serologic testing for ameba when clinical suspicion is high, should be performed in each new patient ( 17 ), and should be considered in patients in remission or with mild stable symptoms who unexpectedly develop a severe or atypi-cal exacerbation ( 18,19 ). Similarly, patients who have recently been admitted to hospital or treated with antibiotics should have stools examined for Clostridium diffi cile , although anti-biotic-associated diarrhea may be present even with a nega-tive assay for C. diffi cile toxin. Th e incidence of C. diffi cile is increasing in UC ( 20 – 23 ), and in infl ammatory bowel disease (IBD) patients it is associated with a more severe course, greater length of hospital stay, higher fi nancial costs, greater likelihood of colectomy, and increased mortality ( 22,24 ). Multiple stool assays may be required for diagnosis