الفهرس 
Introduction
Normal haemoglobinOnly 14 pages are availabe for public view
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Abstract
Beta-thalassaemia and sickle cell anaemia (SCD) represent the most common haemoglobinopathies caused, respectively, by deficient production or alteration of the beta chain of haemoglobin (Hb). Beta-thalassaemia Beta-thalassaemia is caused by the reduced or absent synthesis of the beta globin chains of the haemoglobintetramer; imbalances of globin chains cause hemolysis and impair erythropoiesis. Three clinical and hematological conditions of increasing severity are recognized, i.e., the beta-thalassaemia carrier state, thalassaemia intermedia, and thalassaemia major. The beta-thalassaemia carrier state is clinically asymptomatic and is defined by specific hematological features. Beta thalassaemia intermedia are less severe than beta thalassaemia major and may require episodic blood transfusions. Beta thalassaemia major causes haemolytic anaemia, poor growth, and skeletal abnormalities during infancy. Affected children will require regular lifelong blood transfusions. Transfusion-dependent patients will develop iron overload and require chelation therapy to remove the excess iron. Sickle cell disease SCD is an autosomal, recessive haemoglobinopathy characterized by haemolytic anaemia, intermittent occlusion of small vessels leading to acute and chronic tissue ischemia, and organ dysfunction. In SCD, a point mutation on the β-globin gene results in glutamine acid substituting for valine at position 6 of the amino acid sequence. This single amino acid substitution results in the formation of sickle cell haemoglobin. Red blood cell transfusions are a therapeutic main stay in SCD and repeated transfusions can result in iron overload. Endocrine complications in thalassaemia & SCD patients Endocrine dysfunction is the most common and earliest organ toxicity seen in thalassaemia & SCD patients with chronic iron-induced cellular oxidative damage and can be seen in those without clinical evidence of iron overload. The most common types of endocrine disorders include growth failure, hypogonadism, hypothyroidism, carbohydrate disorders.