Measuring the amount of iron deposited in the liver is considered definitive for iron overload. This may be done by liver biopsy, computed tomography (CT), or magnetic resonance imaging (MRI). Demonstrating iron in parenchymal liver cells helps determine disease severity. Liver sections obtained by biopsy are stained with Perls Prussian blue, which stains iron present in parenchymal cells. A photomicrograph of this reaction is shown.
Although a liver biopsy may not be necessary to diagnose HH, it offers the advantage of detecting liver fibrosis if present. Molecular tests for mutations associated with HH are considered the gold standard of current HH testing. A liver biopsy is not needed to diagnose all patients suspected of having HH but may be ordered in some cases.
1. Image courtesy of John Woosley, MD.