The nature of latent pulmonary involvement in primary biliary cirrhosis.

Primary biliary cirrhosis is a disease of unknown aetiology, resulting in progressive granulomatous destruction of small intrahepatic bile ducts. The rate at which this occurs varies considerably producing a wide clinical spectrum of the disease itself, as well as expression in other organs. Pulmonary manifestations in PBC have only been intermittently reported. Nevertheless in practice, a vast array of pathophysiological mechanisms can be implicated for the pulmonary dysfunction seen in some of these patients. The observed clinical features can be attributed to pulmonary vascular abnormalities, to a secondary 'fibrosing alveolitis', or indeed to the emergence of a granulomatous disorder in the lungs similar to sarcoidosis. Physicians should thus be aware of such potential lung complications, which can occur not only during the course of the PBC but also following liver transplantation.