Increased frequency of autoimmune diseases in patients with primary sclerosing cholangitis

OBJECTIVES: Primary sclerosing cholangitis (PSC) is a chronic cholestatic l iver disease of unknown origin that mostly affects male patients with infla mmatory bowel disease (IBD). The immune system is believed to be involved i n the etiology/pathogenesis as these patients present with several immunolo gical disturbances. Susceptibility to develop primary sclerosing cholangiti s is partly determined by genes in the HLA complex. The aim of this study w as to compare the prevalence of autoimmune disorders in IBD patients with a nd without PSC and to correlate the presence of autoimmune disorders in PSC to outcome and HLA association. METHODS: One hundred nineteen PSC patients were included in the study. Each PSC patient with IBD was matched to a IBD patient without PSC. The presenc e of autoimmune disorders was carefully evaluated in each group. Moreover, comparisons between PSC patients with and without autoimmune disorders were performed. RESULTS: Twenty-five percent of the PSC patients had at least one autoimmun e disorder outside the liver and colon compared to 9% in the IBD group with out. PSC (p < 0.005). Nine of the PSC patients had two or more autoimmune d iseases compared to only one patient in the IBD group (p < 0.02). The PSC p atients with and without associated autoimmune disease did not differ in cl inical presentation, outcome of PSC or HLA alleles. A significant overrepre sentation of DRB1"03 was still present after excluding PSC patients with co ncomitant autoimmune diseases outside the liver and colon compared to a hea lthy Swedish control group. CONCLUSIONS: Autoimmune disorders are more frequent among PSC patients comp ared to IBD patients without liver disease. Associated autoimmune diseases in PSC patients does not influence the outcome or clinical presentation of PSC. (C) 2000 by Am. Cell. of Gastroenterology.