الفهرس 
INTRODUCTION .Only 14 pages are availabe for public view
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Abstract
Hemoglobinopathies are conditions which comprise a very large number of genetic, biochemical and physiological entities.
β-thalassemia encompasses a group of monogenic diseases that have in common defective synthesis of β-globin. The defects involved are extremely heterogeneous and give rise to a large phenotypic spectrum, with patients that are almost asymptomatic to cases in which regular blood transfusions are required to sustain life. The patients suffer from chronic anemia due to a process called ineffective erythropoiesis (IE). The sequelae of IE lead to extramedullary hematopoiesis (EMH) with massive splenomegaly.
SCD is characterized by abnormal hemoglobin production, hemolytic anemia and intermittent occlusion of small vessels which may affect the brain, pulmonary vessels, spleen, bone marrow, kidney, retina, penis or other tissues resulting in sequelae such acute chest syndrome with pulmonary infarction, stroke or splenic infarction. The type and severity of complications vary significantly between individuals from mild symptoms to hospitalization with serious life threatening complications.