Anemia hemosiderin

Reduction of germinal centers and increased hemosiderin deposits were seen histologically in the spleen of Sprague-Dawley rats after a single oral dose of 25 g/kg (Christian et al. 1986a). Mild anemia developed in rhesus monkeys after a single oral dose of 70 g/kg (McConnell et al. 1978a). No effects were found in minks exposed acutely to a lethal dose of 2,3,7,8-TCDD (7.5 g/kg) (Hochstein et al. 

An 80-year-old Japanese woman presented with epigastric discomfort and nausea. She had a history of hypertension, rheumatoid arthritis, iron deficiency anemia, chronic renal insufficiency, and had taken oral ferrous sulfite for 19 months. Endoscopic examination of the duodenum showed marked pigmentation of the duodenal mucosa. Histological examination showed that the pigment had histochemical features compatible with hemosiderin and was located mainly within macrophage lysosomes in the lamina propria. Ferrous sulfite was withdrawn and the pigmentation disappeared within 7 months. 

As noted earlier, transferrin saturation (i.e., serum iron level divided by the TIBC) is also useful in assessing IDA. Low values likely indicate IDA, although low serum transferrin saturation values may also be present in inflammatory disorders. Fortunately, the TIBC usually helps to differentiate the diagnosis in these patients a TIBC greater than 400 mcg/dL suggests IDA, whereas values below 200 mcg/dL usually represent inflammatory disease. With continued progression of IDA, anisocytosis occurs and poikilocytosis develops, as seen on peripheral smear and indicated by increased RDW. In rare cases, a bone marrow examination can be performed to assess bone marrow iron stores. Bone marrow examination reveals absent iron stores in IDA. Documenation of decreased hemosiderin can confirm the diagnosis of IDA. In microcytic anemias due to all other causes, iron stores are detectable. 

Hemosiderin, a mammalian non-heme iron storage protein with a similar function to ferritin. It contains iron oxyhy-droxide cores similar to those of ferritin, and it has been reported that these cores are present as large, dense, membrane-bound aggregates in vivo. It is assumed that hemosiderin is produced by lysosomal degradation of ferritin or possibly of ferritin polymers. Hemosiderin is deposited in the liver and spleen, especially in diseases such as pernicious anemia or hemochromatosis. The deposits are yellow to brown-red pigments. The iron content of hemosiderin is about 37%. Nonheme iron is also abundantly present in the brain in different forms. In the so-called high-molecular-weight complexes, iron is bound to hemosiderin and ferritin. The total amount of iron may differ in health and disease [F. A. Fischbach et al, J. Ultrastruct. Res. 1971, 37, 495 M. P. Weir, T. J. Peters, Biochem.J. 1984, 223, 31]. 

Hemosiderin an iron storage protein of the mammalian organism, functionally related to Ferritin (see). H. is deposited in the liver and spleen (hemosiderosis), particularly in diseases associated with increased blood destruction, such as pernicious anemia, or with increased iron resorption (hemochromatosis), or even in hemorrhages Most of the deposits are located in the liver, which may contain up to 50 g H., compared with the normal content of 120 to 300 mg H. H. from horse spleen consists of 26-34 % iron(III), and up to 35 % protein (aposiderin). The rest is made up of octasubstituted porphyrin, mucopolysaccharides and fatty acid esteis. 

Hemoglobin breakdown is covered in the section on hemolytic anemias. The released iron is not excreted, but is stored in the form of ferritin or hemosiderin. 

Fig. 30. Spleen of a pyridoxine-deficient pig. Reduction of red pulp and deposition of hemosiderin in pulp capsule and trabeculae. Animal was suffering from severe microcytic anemia.

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