Sclerosing cholangitis

Primary sclerosing cholangitis is a chronic cholestatic liver disease of unknown etiology that leads to progressive obliterative fibrosis of the biliary tree. The disease progresses in most patients to death from liver failure or cholangiocarcinoma. The etiology remains obscure, but immune-mediated factors are thought to be involved in its pathogenesis, as suggested by the strong HLA associations and a circulating antineutrophil cytoplasmic antibody. The neutrophil antigen remains unknown, and this test is not yet useful as a diagnostic tool. Biliary expression of heat shock proteins is enhanced, but this phenomenon is nonspecific and is also seen in other forms of chronic cholestasis. The disease is strongly associated with ulcerative colitis, and the risk of colorectal cancer is high. Patients may have biliary calculi, previously thought to exclude the diagnosis. Endoscopic retrograde cholangiopancreatography remains the gold standard for diagnosis, but false-positive results are a possibility. Liver biopsy is nonspecific and subjected to sampling variability. No medical treatment is of proven benefit, and surgical procedures are best avoided. Orthotopic liver transplantation remains the only effective treatment, and the 5-year survival rate is up to 89%.