Correlation between Serum Ferritin and Thyroid Hormones Level in Children with Thalassemia

Background: Thalassemia is a group of hereditary blood disorder characterized by reduced or absent globin chain synthesis resulting in transfusion dependent anaemia and iron overload. Due to regular blood transfusion and inadequate chelation therapy patient develop multiorgan dysfunction. Objectives: To find any correlation between serum ferritin and thyroid hormones level in children with transfusion dependent thalassemia. Methods: This cross-sectional study was carried out in the department of Paediatrics and department of Medicine, Sylhet MAG Osmani Medical College Hospital between June, 2021 to May, 2022, on one hundred children with transfusion dependent thalassemia who were on more than 12 times blood transfusion but did not take any chelation therapy and whose serum ferritin level were > 1000 ng/ml. Assessment of their thyroid hormones level and statistically its correlation with serum ferritin were done. Result: A total of 53 (53%) male and 47 (47%) female were included in this study. The mean age of the patients was 9.47 ±3.63 years. Mean serum ferritin was 1980±1126.19 ng/ml, mean serum TSH was 3.55±2.08 µIU/ml, mean serum free T4 was 1.10±0.18 ng/ml, mean serum free T3 was 3.64±0.37 pg/ml. Subclinical hypothyroidism and euthyroid were found in 20 patients (20%) and 80 patients (80%) respectively. No overt hypothyroidism or hyperthyroidism were found. Mean serum ferritin in subclinical hypothyroid and euthyroid were 2407±995.37 ng/ml and 1875.59±1131.18 ng/ml respectively which difference was statistically significant (P value <0.05). Scattered diagram was done and it showed linear correlation between serum ferritin and serum TSH of subclinical hypothyroid group. No linear correlation was found between serum ferritin and F.T3 and F.T4 on scattered diagram. Positive (Pearson) correlation was found between serum ferritin and serum TSH of subclinical hypothyroid group and strong positive (Pearson) correlation (r=0.74, P=0.02) was found between them. Conclusion: This study showed that good percentages of children with transfusion dependent thalassemia are suffering from subclinical hypothyroidism. There is positive correlation between serum ferritin level and subclinical hypothyroidism.