A liver biopsy stained with Prussian blue demonstrating ferric iron in a patient with hemochromatosis.
A liver biopsy stained with Prussian blue demonstrating ferric iron (+3) in a patient with hemosiderosis.
Hemochromatosis and hemosiderosis are both conditions that cause the liver to accumulate excess iron.
Hereditary hemochromatosis can be defined as a genetic disease that causes iron accumulation in the parenchymal cells of the liver, heart, and other organs under normal iron intake. Damage to the parechymal cells of these organs can occur if the excess iron is not removed. Liver biopsies are essential to diagnose the excess iron storage and allow the pathologist to assess cellular damage. Patients with hereditary hemochromatosis are treated with therapeutic phlebotomy or bloodletting. Bloodletting is a technique that is centuries old. The phlebotomy technique used for patients with hereditary hemochromatosis is identical to the procedure that is used for donating blood.
Hemosiderosis can be defined as a non-genetic disease that causes iron to deposit in organs like the liver and spleen. The cause of hemosiderosis is due to an increase in iron intake and may be attributed to transfusion, excess dietary iron consumption, or the breakdown of red blood cells. Liver biopsies are also used to diagnose hemosiderosis and also allow the pathologist to assess cellular damage. However, cellular damage is less common in hemosiderosis.
A liver biopsy is used to diagnose both hereditary hemochromatosis and hemosiderosis. Iron can be seen as a brown pigmentation on a hemotoxylin and eosin (H&E) stained tissue slide but may be difficult to distinguish from other pigments. Therefore, an iron stain is commonly used to positively identify iron in the liver. In early diagnosis, iron storage patterns in the liver biopsy are used by the pathologist to distinguish hereditary hemochromatosis from hemosiderosis. Distinction between hereditary hemochromatosis and hemosiderosis becomes more difficult for the pathologist as both of these diseases progress because iron storage patterns become similar.