الفهرس 
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Abstract
Beta-thalassemia is prevalent in Mediterranean countries, the Middle East, Beta Thalassemia is the most common chronic hemolytic anemia in Egypt (85.1%). A carrier rate of 9-10.2% has been estimated in 1000 normal random subjects from different geographical areas of Egypt; and it represents the major cause of iron overload in Mediterranean countries.
The thalassemia syndromes are hemoglobin disorders that result from significantly reduced or absent synthesis of either the α- or β-globin chains. The result is a chronic hemolytic anemia with ineffective erythropoiesis and bone marrow overstimulation.
The reduced amount (beta+) or absence (beta0) of beta globin chains result in a relative excess of free alpha globin chains that precipitate in erythroid precursors in the bone marrow, leading to their premature death and so ineffective erythropoiesis.
Peripheral hemolysis contributing to anemia and occurs when insoluble alpha globin chains induce membrane damage to the peripheral erythrocytes.
If a regular transfusion program that maintains a minimum Hb concentration of 9.5 to 10.5 g/dL is initiated, growth and development tends to be normal up to 10 to 12 years.
Iron overload is inevitable in patients requiring life-long transfusion support. Each unit of transfused red cells introduces 200 to 250 mg of elemental iron into the body. When iron stores overwhelm the ability of reticuloendothelial cells to sequester them, parenchymal iron overload develops.
Complications of iron overload include growth retardation and failure or delay of sexual maturation. Later iron overload-related complications include involvement of the heart (dilated cardiomyopathy or rarely arrhythmias), liver (fibrosis and cirrhosis), and endocrine glands (diabetes mellitus, hypogonadism and insufficiency of the parathyroid, thyroid, pituitary, and, less commonly, adrenal glands).
New approaches for monitoring of iron overload include magnetic resonance imaging, which offer a noninvasive measure of iron deposition in the heart and liver.
Non-invasive measurement of liver iron concentration has also been achieved using a magnetic resonance technique based on proton transverse relaxation rates within the liver.
Hepcidin, a circulating hormone produced by the liver, plays a central role in the regulation of systemic iron homeostasis. Hepcidin represents a negative regulator of iron absorption and macrophage iron release.
Thalassemia major is the best studied human models of hepcidin modulation by the combined and opposite effect of both ineffective erythropoiesis and transfusion dependent iron overload. Regular transfusions, in fact, induce a huge tissue iron accumulation, but also inhibit erythropoietic drive; hepcidin levels are markedly reduced in thalassemia, due to the erythropoietic drive and despite systemic tissue iron overload.
from the previously mentioned data about the critical role of hepcidin in iron regulation and lack of a single simple non expensive; non invasive technique that reflect the actual tissue iron load; In this study; we tried to determine the hepcidin/ferritin ratio and to define its biological value by correlating it to liver iron concentration as determined by MRI.
In this context we studied the hematological, biochemical and radiological profile of 45 thalassemic children attending the Hematology Clinic in Suez Canal University Hospital.