Editing Ulcerative colitis (section)

==Prognosis==
Poor prognostic factors include: age < 40 years upon diagnosis, extensive colitis, severe colitis on endoscopy, prior hospitalization, elevated CRP and low serum albumin.<ref name=ACG_Guidelines_2019 />

===Progression or remission===
People with ulcerative colitis usually have an intermittent course, with periods of disease inactivity alternating with "flares" of disease. People with proctitis or left-sided colitis usually have a more benign course: only 15% progress proximally with their disease, and up to 20% can have sustained remission in the absence of any therapy. A subset of people experience a course of disease progress rapidly. In these cases, there is usually a failure to respond to medication and surgery often is performed within the first few years of disease onset.<ref>{{cite journal | vauthors = Kevans D, Murthy S, Mould DR, Silverberg MS | title = Accelerated Clearance of Infliximab is Associated With Treatment Failure in Patients With Corticosteroid-Refractory Acute Ulcerative Colitis | journal = Journal of Crohn's & Colitis | volume = 12 | issue = 6 | pages = 662–669 | date = May 2018 | pmid = 29659758 | doi = 10.1093/ecco-jcc/jjy028 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Horio Y, Uchino M, Bando T, Chohno T, Sasaki H, Hirata A, Takesue Y, Ikeuchi H | title = Rectal-sparing type of ulcerative colitis predicts lack of response to pharmacotherapies | journal = BMC Surgery | volume = 17 | issue = 1 | pages = 59 | date = May 2017 | pmid = 28526076 | pmc = 5437574 | doi = 10.1186/s12893-017-0255-5 | doi-access = free }}</ref> People with more extensive disease are less likely to sustain remission, but the rate of remission is independent of the severity of the disease.<ref>{{cite book |doi=10.1016/B978-1-4160-6189-2.00112-8 |chapter=Ulcerative Colitis |title=Sleisenger and Fordtran's Gastrointestinal and Liver Disease |year=2010 |last1=Osterman |first1=Mark T. |last2=Lichtenstein |first2=Gary R. |pages=1975–2013.e9 |isbn=9781416061892 }}</ref> Several risk factors are associated with eventual need for colectomy, including: prior hospitalization for UC, extensive colitis, need for systemic steroids, young age at diagnosis, low serum albumin, elevated inflammatory markers (CRP & ESR), and severe inflammation seen during colonoscopy.<ref name=AGAClinicalPractice2020 /><ref name=ACG_Guidelines_2019 /> Surgical removal of the large intestine is necessary in some cases.<ref name=ACG_Guidelines_2019 />

===Colorectal cancer===
The risk of [[colorectal cancer]] is significantly increased in people with ulcerative colitis after ten years if involvement is beyond the [[splenic flexure]]. People with backwash ileitis might have an increased risk for colorectal carcinoma.<ref>{{cite journal | vauthors = Patil DT, Odze RD | title = Backwash Is Hogwash: The Clinical Significance of Ileitis in Ulcerative Colitis | journal = The American Journal of Gastroenterology | volume = 112 | issue = 8 | pages = 1211–1214 | date = August 2017 | pmid = 28631729 | doi = 10.1038/ajg.2017.182 | s2cid = 10801391 }}</ref> Those people with only proctitis usually have no increased risk.<ref name=ACG_Guidelines_2019 /> It is recommended that people have screening [[colonoscopies]] with random biopsies to look for [[dysplasia]] after eight years of disease activity, at one to two year intervals.<ref>{{cite journal | vauthors = Leighton JA, Shen B, Baron TH, Adler DG, Davila R, Egan JV, Faigel DO, Gan SI, Hirota WK, Lichtenstein D, Qureshi WA, Rajan E, Zuckerman MJ, VanGuilder T, Fanelli RD | title = ASGE guideline: endoscopy in the diagnosis and treatment of inflammatory bowel disease | journal = Gastrointestinal Endoscopy | volume = 63 | issue = 4 | pages = 558–565 | date = April 2006 | pmid = 16564852 | doi = 10.1016/j.gie.2006.02.005 }}</ref>

===Mortality===
People with ulcerative colitis are at similar<ref name=Gamborg /> or perhaps slightly increased overall risk of [[death]] compared with the background population.<ref name="daSilva">{{cite journal | vauthors = da Silva BC, Lyra AC, Rocha R, Santana GO | title = Epidemiology, demographic characteristics and prognostic predictors of ulcerative colitis | journal = World Journal of Gastroenterology | volume = 20 | issue = 28 | pages = 9458–9467 | date = July 2014 | pmid = 25071340 | pmc = 4110577 | doi = 10.3748/wjg.v20.i28.9458 | doi-access = free }}</ref> However, the distribution of causes-of-death differs from the general population.<ref name=Gamborg>{{cite journal | vauthors = Jess T, Gamborg M, Munkholm P, Sørensen TI | title = Overall and cause-specific mortality in ulcerative colitis: meta-analysis of population-based inception cohort studies | journal = The American Journal of Gastroenterology | volume = 102 | issue = 3 | pages = 609–617 | date = March 2007 | doi = 10.1111/j.1572-0241.2006.01000.x | pmid = 17156150 | s2cid = 2086542 }}</ref> Specific risk factors may predict worse outcomes and a higher risk of mortality in people with ulcerative colitis, including ''C. difficile'' infection<ref name=ACG_Guidelines_2019 /> and [[cytomegalovirus infection]] (due to reactivation).<ref>{{cite journal | vauthors = Nguyen M, Bradford K, Zhang X, Shih DQ | title = Cytomegalovirus Reactivation in Ulcerative Colitis Patients | journal = Ulcers | volume = 2011 | pages = 1–7 | date = January 2011 | pmid = 21731826 | pmc = 3124815 | doi = 10.1155/2011/282507 | doi-access = free }}</ref>