Evaluation of Bone Mineral Density in Children with Thalassemia Major

Abstract

Aim: Fragile bones develop due to various factors in thalassemic patients. Even with optimum management, osteoporosis occurs, contributing to morbidity in majority of patients with thalassemia major (TM). Our aim was to evaluate bone health of thalassemic children using biochemical parameters and bone mineral density (BMD), and to emphasize the precautionary measures and early diagnosis of osteoporosis. Material and Methods: Thirteen children (5 females, 8 males, age <18 years) with TM were included in the study. Age, duration, weight, height, transfusion frequency, medication use were recorded. Following laboratory analysis were obtained: Whole blood count, fasting blood glucose, ferritin, alanine aminotransferase, aspartate aminotransferase, calcium, phosphorus, alkaline phosphatase, thyroid stimulating hormone, free thyroxin, and intact parathyroid hormone (iPTH). BMD was determined using dual energy X-ray absorptiometry (DXA) from femur and lumbar vertebrae. Patients with DXA Z-score <-2 was defined as osteoporotic. Results: The mean age was 7.85±3.17 years and body mass index (BMI) was 14.68±1.93 kg/m2. The rest of the results were as follows: Lumbar BMD 0.464±0.108 g/cm2; total femur BMD 0.581± 0.114 g/cm2; lumbar DEXA Z-score 2.44±1.60; total femur DEXA -0.93±1.19. Osteoporosis ratio was determined as 69% in the lumbar vertebrae and 10% in the femur. A significant positive correlation was found between lumbar-femoral BMD and BMI, and a significant negative correlation was observed between femoral BMD and iPTH. Conclusion: BMD is low in thalassemic children. Despite regular transfusions and chelation therapy, osteoporosis starts early in life. (Turkish Journal of Osteoporosis 2012;18: 72-7)

Keywords

• Thalassemia major
• bone mineral density
• osteoporosis