To assess body composition (fat mass, lean mass, and bone mass) in pediatric patients with beta thalassemia major using appropriate tools (e.g.,Bioelectrical impedance analysis (BIA)).

To evaluate the association between body composition and clinical parameters such as transfusion frequency, nutritional status, serum ferritin levels, endocrine complications.

Thalassemias are severe inherited anemias characterized by microcytic, hypochromic, and short-lived red blood cells due to defective hemoglobin synthesis(1) β-thalassemias are a heterogeneous group of hereditary hemoglobinopathies characterized by defects in the β-globin chain of hemoglobin and belong to autosomal recessive disorders(2) Three clinical and hematological conditions of increasing severity are recognized and include beta-thalassemia carrier state, thalassemia intermedia, and thalassemia major (3, 4).

Regular blood transfusion is a vital treatment in β-thalassemia major patients to prevent the consequences of anemia. Iron overloading is frequently observed in β-thalassemia major patients with transfusion therapy . Excessive iron can cause multiple organ damage (5, 6, 7, 8).

Patients with β-thalassemia major (BTM) suffer from several patterns of growth retardation including short stature, underweight, wasting, and decreased bone density(9, 10).

Impaired nutritional status has been commonly observed in patients with thalassemia major. Specific nutritional deficiencies, such as vitamin D deficiency, are also often observed due to increased losses of micronutrients or increased endogenous requirements (11).

Patients suffering from thalassemia major have impaired body composition, especially whole-body lean mass and bone mineral density(12, 13). Body composition is influenced by many parameters including age, gender, endocrine system status, nutrition, and exercise (14). All the above parameters are impaired in patients with thalassemia major in addition to hyperactivity of bone marrow, iron overload, and diminished bone mineral density (15, 16).

Patients with thalassemia tend to have increased adiposity(17, 18). These alterations in body composition are more frequently seen in thalassemic patients compared to the general population and are related to the high prevalence of sarcopenic obesity (19).

Bioelectrical impedance analysis (BIA), a technique using electrical properties to analyze body composition. Using BIA provides a more accurate and non-invasive assessment of muscle mass(20).

Body composition in pediatric patients with beta_thalassemia major has not been well studied, especially in Egypt.There is a lack of sufficient data addressing changes in muscle mass, fat distribution, and their metabolic consequences in this group of patients.

This study will provide new insights into body composition profile of thalassemic children in Assisut University Children's Hospital.The results are expected to fill an important gap in knowledge, support early detection of abnormalities, and contribute to better strategies for management and prevention of long_term complications.

Inclusion Criteria:

• Children aged 5-18 years
• Diagnosed with beta thalassemia major
• Receiving regular transfusions
• Informed consent/assent provided.

Exclusion Criteria:

• Presence of other chronic systemic diseases
• On medications that significantly affect body composition (e.g., steroids)
• Severe physical or cognitive disability interfering with assessment

Children and adolescents aged 5 to 18 years with a confirmed diagnosis of beta thalassemia major attending Assiut University Children's Hospital. Both sexes will be included.