Iron Overload (with Attention to Genetic Testing and Diagnosis/Management of HFE Wild Type Patients)

The discovery of the HFE, HJV, HAMP, TfR2, and SLC40A1 genes and preliminary understanding of their roles in iron homeostasis have contributed tremendously to our understanding of the pathogenesis of genetic hemochromatosis. Although several new models of iron metabolism have been proposed, some key "sensor" steps of iron absorption in the enterocytes and of iron storage in hepatocytes and other cells remain unclear. A diagnosis of non-HFE genetic hemochromatosis should be considered in patients with unexplained iron overload who do not have the common mutations in the HFE genes. Phenotypic evaluation such as liver biopsy and measurement of hepatic iron concentration remain important in non-HFE hemochromatosis because mutations in other genes are rare and there are no other available noninvasive tests to confirm the diagnosis. Phlebotomy remains the mainstay of therapy also for non-HFE hemochromatosis. However, phlebotomy may not be well tolerated in certain forms of non-HFE hemochromatosis such as "ferroportin disease."