Iron and chronic viral hepatitis: emerging evidence for an important interaction.

Iron is an essential element for cell survival; it serves as a cofactor for essential enzymes in oxidative metabolism and (in the form of heme) as the major oxygen transporter in most forms of life on earth. Both deficiency and excess of iron often lead to disease. Iron is necessary for the proliferation of microorganisms and neoplastic cells. The presence of iron overload facilitates infection, as evidenced by the increased risk of persons with hemochromatosis to certain infections and by the fact that patients with lesser amounts of hepatic iron appear to respond better to interferon therapy for chronic viral hepatitis than those with larger amounts of hepatic iron. Viral hepatitis is a common cause of morbidity and mortality. Recent studies suggest that there is a key link between iron metabolism and the pathophysiology of viral hepatitis. The lobular and cellular distribution of iron in the liver may be as important as the total quantity of iron present. Whether iron removal will prove useful in the long-term management of chronic viral hepatitis is an issue in need of further well-designed, randomized, controlled trials.