Il sovraccarico di ferro e la terapia chelante

Clinical evidence for heart, liver and endocrine toxicity due to iron has been provided by studies of patients with genetic hemochromatosis (GH) and secondary hemochromatosis due to beta-thalassemia or to other chronic transfusion dependent anemias. Direct measurement of hepatic iron concentrations is the most sensitive method for determining the body iron burden. Phlebotomy is the choice treatment in primary iron overload (GH): 500 ml of blood removed contain about 200 mg of iron; it should be possible to remove up to 20 g of iron in a single year. Daily intramuscular injection or subcutaneous infusion of 0.5 to 1.0 g of iron in a single year. Daily intramuscular injection or subcutaneous infusion of 0.5 to 1.0 g of chilating agent desferrioxamine (DFO) results in mobilization and urinary excretion of up to 20 mg of iron/day. In beta-thalassemia patients. During treatment with DFO, significant reduction in liver iron concentration with little change in hepatic fibrosis were seen. Recently an oral iron chelator Deferiprone (L1) has been used in a group of patients with thalassemia major. The results demonstrate good efficacy in a short-term treatment; the toxicity is under evaluation.