How we manage patients with hereditary haemochromatosis

In the late 1800s, hemochromatosis was considered an odd autoptic finding. More than a century later, it was finally recognized as a hereditary, multi-organ disorder associated with a polymorphism that is common among white people: a 845G-->A change in HFE that results in C282Y in the gene product. Hemochromatosis is now a well-defined syndrome characterized by normal iron-driven erythropoiesis and the toxic accumulation of iron in parenchymal cells of liver, heart, and endocrine glands. It can be caused by mutations that affect any of the proteins that limit the entry of iron into the blood. In mice, deletion of the iron hormone hepcidin and any of 8 genes that regulate its biology, including Hfe, transferrin receptor 2 (Tfr2), and hemojuvelin (Hjv) (which all sense the accumulation of iron that hepcidin corrects) or ferroportin (Fpn) (the cellular iron exporter down-regulated by hepcidin), cause iron overload but not organ disease. In humans, loss of TfR2, HJV, and hepcidin itself or FPN mutations result in full-blown hemochromatosis. Unlike these rare instances, in white people, homozygotes for C282Y polymorphism in HFE are numerous, but they are only predisposed to hemochromatosis; complete organ disease develops in a minority, when these individuals abuse alcohol or from other unidentified modifying factors. HFE gene testing can be used to diagnose hemochromatosis, but analyses of liver histology and clinical features are still required to identify patients with rare, non-HFE forms of the disease. The role of hepcidin in the pathogenesis of hemochromatosis reveals its similarities to endocrine diseases such as diabetes and indicates new approaches to diagnosis and management of this common disorder in iron metabolism. Copyright (c) 2010 AGA Institute. Published by Elsevier Inc. All rights reserved. Show more

The course of hereditary hemochromatosis may depend on the degree of iron overload and the time of therapeutic intervention. This analysis evaluates the impact of early diagnosis and iron removal on survival and complications in hereditary hemochromatosis. A Cohort of 251 patients with hemochromatosis was followed up for 14.1 +/- 6.8 years. Survival was reduced in the total group of patients when compared with a matched normal population. Survival in noncirrhotic and nondiabetic patients and in patients diagnosed between 1982 and 1991 was identical with rates expected. Survival was reduced in patients with severe iron overload vs. those with less severe overload. The percentage of early diagnoses increased threefold between 1947 and 1969 to that between 1970 and 1981; there was only a further 20%-25% increase in the last decade. Deaths caused by liver cancer, cardiomyopathy, liver cirrhosis, and diabetes mellitus were increased as compared with expected rates. Liver cancers were associated with cirrhosis and amount of mobilizable iron but not with hepatitis B or C markers. Prognosis of hemochromatosis and most of its complications, including liver cancer, depend on the amount and duration of iron excess. Early diagnosis and therapy largely prevent the adverse consequences of iron overload. Show more

Haemochromatosis is now known to be an iron-storage disease with genetic heterogeneity but with a final common metabolic pathway resulting in inappropriately low production of the hormone hepcidin. This leads to increase in intestinal absorption and deposition of excessive amounts of iron in parenchymal cells which in turn results in eventual tissue damage and organ failure. A clinical enigma has been the variable clinical expression with some patients presenting with hepatic cirrhosis at a young age and others almost asymptomatic for life. Research is unravelling this puzzle by identifying environmental factors-especially alcohol consumption-and associated modifying genes that modulate phenotypic expression. A high index of suspicion is required for early diagnosis but this can lead to presymptomatic therapy and a normal life expectancy. Venesection (phlebotomy) therapy remains the mainstay of therapy, but alternative therapies are the subject of current research. Show more