الفهرس | Only 14 pages are availabe for public view |
Abstract Introduction: Beta thalassemia major (BTM) is characterized by anemia and iron overload, especially with inadequate chelation therapy. Dual energy x-ray absorptiometry (DXA) may misanalyse bone measurements due to iron deposition in organs such as the liver. Aim: The aim of this work was to study difference between the posterior-anterior spine measurements of bone mineral content (BMC), area (BA) and density (BMD) in poorly chelated beta thalassemia patients with and without inclusion of the liver in the DXA analysis. Methods: We studied hemoglobin and serum ferritin concentrations in 67 child patients with BTM. Posteroanterior spine measurements BMC, BA and areal BMD were performed using DEXA scan, analysis was carried out including and excluding (manually) the iron overloaded liver. Machine generated Z-scores of L1-L4 BMD were used for analysis. Results: The mean age of the study group was7.66 ± 1.97 yr. Mean hemoglobin and serum ferritin concentrations were 5.20 ± 0.71 g/dl and 2287.33 ± 1101.16 ng/ml, respectively. The mean BMC, BA, and BMD at the lumbar spine were 16.60 ± 4.11 g, 36.70 ± 7.21 cm2 and 0.44 ± 0.08 g/cm2 respectively with inclusion of liver that is standard machine analysis. After the liver was excluded from the analysis, the mean BMC, BA, and BMD were 16.87 ± 4.16 g, 36.04 ± 6.01 cm2 and 0.46 ± 0.08 g/cm2, respectively and the BMD was significantly greater (p < 0.05). Mean BMD Z-score was -4.1 – 1.9, which significantly (p < 0.05) improved to -4.2 – 1.9 after exclusion of the liver from the analysis. Conclusion: Based on the results of the current study, the caution needs to be exercised in the analysis of DXA scans in poorly chelated thalassemic patients; inclusion of the iron-overloaded liver in the tissue analysis may exaggerate the deficit in bone density parameters. Manual analysis may be required to reduce the pseudo effect of highly attenuating material like the iron-overloaded liver on bone parameters at the lumbar spine. |