The role of environmental factors in primary biliary cirrhosis.

The etiology of primary biliary cirrhosis (PBC) is enigmatic, although it is clearly related to a combination of genetic predisposition and environmental stimulation. PBC is a chronic autoimmune cholestatic liver disease that occurs throughout the world with a reported latitudinal gradient in prevalence and incidence. PBC is also characterized by a 60% concordance in monozygotic twins and is considered a model autoimmune disease because of several features common to other conditions and the relatively homogeneous serological and biochemical features. Several risk factors have been suggested to be associated with PBC, including exposure to infectious agents and chemical xenobiotics. This review will attempt to place such factors in perspective.