Pulmonary manifestations of chronic liver disease.

Several lung disorders can occur as a consequence of chronic liver disease. In addition to the common findings of splanchnic and systemic vasodilatation in patients with chronic liver disease, pulmonary vasodilatation may also occur. This "hepatopulmonary syndrome' results in hypoxemia through pulmonary vasodilation and VA/Q mismatch, and in its advanced form leads to significant intrapulmonary arteriovenous shunting. Portal hypertension commonly results in the development of ascites, which may cause a restrictive lung pattern or pleural effusions. Rarely, thrombi formed in congested portal vein branches pass through portosystemic shunts and cause pulmonary hypertension, and plexogenic pulmonary hypertension may also occur in patients with portal hypertension. The autoimmune liver diseases, primary biliary cirrhosis and autoimmune hepatitis, may be accompanied by immune-mediated lung disease. These pulmonary abnormalities represent important extrahepatic manifestations of chronic liver disease.