Ulcerative Colitis with and without Primary Sclerosing Cholangitis: Two Different Diseases?

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown origin and an important hepatobiliary complication of inflammatory bowel diseases (IBD), especially ulcerative colitis (UC). When further differentiated, about 3-8% of UC patients suffer from PSC, whereas among Crohn's disease patients the reported prevalence of PSC is probably between 1 and 3.5%. Although it was reported from Japan that the frequency of PSC in UC was only 34%, the same registry data indicated that the prevalence was up to 57% among young patients with PSC even in Japan, which is comparable to the 60-80% in Europe and the US. Additionally, the clinical features of UC in patients with PSC are different from those in patients without PSC, for instance, rectal sparing and right-sided dominance.