title: Sclerosing cholangitis.
abstract: OBJECTIVE
  Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by strictures of the biliary tree. It is closely associated with inflammatory bowel disease, particularly ulcerative colitis, although the precise etiology remains unknown. The prevalence of PSC, with its attendant medical burdens, appears to be higher than previously estimated; consequently, increasing numbers of patients are being diagnosed and treated in secondary care.
  
  
  RESULTS
  Research into etiopathogenesis, epidemiology, small-duct PSC, and associations with cholangiocarcinoma and colorectal carcinoma are discussed, along with medical therapy and transplantation.
  
  
  CONCLUSIONS
  Small-duct PSC is a distinct clinical entity associated with a benign course and minimal risk of cholangiocarcinoma compared with large-duct PSC. The incidence of gall bladder cancer is increased in patients with PSC, and yearly ultrasonographic screening, with cholecystectomy for gall bladder polyps, is recommended. Recent pilot studies have suggested that high-dose ursodeoxycholic acid (20 mg/kg body weight) may slow liver fibrosis and cholangiographic appearances. Importantly, ursodeoxycholic acid has also been shown to reduce the incidence of colonic dysplasia and colorectal cancer in patients with PSC and ulcerative colitis. Endoscopic therapy, usually balloon dilatation, is effective for benign dominant strictures that are causing jaundice. Liver transplant remains the only treatment in end-stage disease; however, posttransplant recurrence of PSC occurs in as many as one third of patients. Colorectal cancer develops posttransplant in 5 to 10% of those with inflammatory bowel disease. Annual screening colonoscopy is recommended for all patients with PSC with coexisting inflammatory bowel disease.
authors.affiliation: Department of Gastroenterology, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: George R
authors.initials: GR
authors.lastname: MacFaul
authors.forename: Roger W
authors.initials: RW
authors.lastname: Chapman