LAUSR

Abstract Ulcerative colitis (UC) is an inflammatory bowel disease of unknown etiology. It is characterized by a chronic course with periods of aggravations and remissions. Among patients, 25–55% present with ulcerative proctitis (UP) at the time of diagnosis. UP is well-treated disease associated with a good prognosis. UP is characterized by a less aggressive course than the left-sided form of UC and pancolitis, with a good response to topical treatment. Moreover, UP is associated with a lower risk of severe aggravations and systemic and local complications and lower need for colectomy, hospitalization and glucocorticosteroids and immunosuppressive drugs, in comparison with more extensive forms of the disease. Thus, the key issue is to prognose the natural course of the disease in order to identify high-risk patients and apply biological or immunosuppressive treatment early to prevent the development of complications. In this review, we summarize the current knowledge about the natural course of UP and discuss risks and protective factors related to disease progression and current treatment concepts.