Autoimmune cholangitis within the spectrum of autoimmune liver disease

Autoimmune cholangitis is an idiopathic disorder with mixed hepatocellular and cholestatic findings. Our goal was to characterize the disease prospect ively by application of uniform diagnostic criteria. Twenty patients were i dentified and compared with 242 patients with conventional forms of autoimm une liver disease. Patients with autoimmune cholangitis were distinguished from type 1 autoimmune hepatitis (AIH) by lower serum levels of aspartate t ransaminase (AST), gamma-globulin, and immunoglobulin G; higher serum level s of alkaline phosphatase; and lower frequencies of autoantibodies. They we re distinguished from primary biliary cirrhosis (PBC) by higher serum level s of AST and bilirubin, lower serum concentrations of immunoglobulin M, and greater occurrence of autoantibodies. Their female predominance, lower ser um alkaline phosphatase levels, higher frequency of autoantibodies, and abs ence of inflammatory bowel disease differentiated them from primary scleros ing cholangitis (PSC). Laboratory findings ranged widely and did not charac terize individual patients. HLA risk factors were similar to those of type 1 AIH and PBC, and different from those of PSC. Treatment responses to cort icosteroids or ursodeoxycholic acid were poor. Composite histological patte rns resembled mainly PBC or PSC. We conclude that autoimmune cholangitis di agnosed by prospective analysis cannot be assimilated into a single, conven tional, diagnostic category. It may represent variant forms of diverse cond itions, a transition stage, or a separate entity with varying manifestation s.