Abstract

Chronic biliary tract disease is common in cats. It was first reported in 1982, since when a number of case series have described histological and clinical features, including disease associations in some cases with inflammatory bowel disease, pancreatitis, nephritis, hepatic lipidosis and other diseases. However, much remains a mystery: the cause or causes are unknown, no effective treatment has been identified and even the prognosis and long term sequelae are unclear. The disease waxes and wanes in most cats and is a significant cause of reduced quality of life. Evidence suggests that chronic biliary tract disease in cats is not one, but several, diseases and that a subset of cases look remarkably similar histologically and chronically to primary sclerosing cholangitis (PSC) in humans. PSC is a disease of young men which often associates with inflammatory bowel disease, has no good animal model and no effective treatment. Cats might offer a helpful natural model to increase disease understanding for the benefit of both cats and humans. Any feline study on epidemiology, treatment and prognosis of biliary tract disease will be severely hampered by studying several diseases at once. Separating affected cats in to distinct disease categories is essential to facilitate effective future studies on the causes and treatment of these conditions and yet no significant advances have been made in the last 30 years. Improvements in diagnostic imaging and molecular and cell science mean the time is now right to advance our understanding of feline cholangitis, for the benefit of both cats and men.