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Abstract
Thalassemia is a group of inherited hemoglobin disorder characterized by reduced synthesis of one o more of the globin chains leading to imbalance ?/non-? globin synthesis with secondary hemolytic anemia. In Egypt, ?-thalassemia presents a major public health problem, as it constitutes about 85% of the chronic haemolytic anemias, with a gene frequency of 0.03%. Repeated transfusions unaccompanied by iron chelation cause hemosiderosis with secondary functional impairment of most body organs including endocrine glands, liver, heart and bones. On the other hand, iron-chelation therapy with desferal (DFO) prevents hemosiderosis but causes skeletal dysplasia. Bone disease is known as a major cause of morbidity in thalassemia and is caused by many factors mainly the low hemoglobin level and the toxic effect of deposited iron on the endocrine glands and bone cells. It usually bone takes the form of decrease in bone mass (osteopenia or osteoporosis) with bone ache, deformity, short stature or fracture. Bone mass is measured by bone mineral density (BMD) that can be assessed by DEXA. Each patient’s BMD is compared with the mean BMD of age- and sex- matched reference population BMD (Z score)