Evaluation of Serum Ferritin and Anti-Thyroid Peroxidase Antibody Status in Newly Diagnosed Subclinical Cases of Hypothyroidism

Abstract

Background: Serum ferritin concentrations are altered in hypothyroidism, but there is no available literature regarding the status of serum ferritin in anti-thyroid peroxidase (anti-TPO) positive hypothyroidism. The objectives of our study were to evaluate the titer of anti-TPO and serum ferritin in newly diagnosed hypothyroid patients and to find out any difference in serum ferritin concentration between antibody-positive and antibody-negative patients. Methods: A total of 143 subjects above the age of 18 years were recruited, and serum Thyroid Stimulating Hormone (TSH), free T3, free T4, anti-TPO, and ferritin were assayed by chemiluminescence method. According to their serum analysis findings, three groups were made as Group 1 of 49 subjects with hypothyroidism and anti-TPO positive, Group 2 of 47 subjects with hypothyroidism and anti-TPO negative, and Group 3 of 47 euthyroid and anti-TPO negative controls. Results: Kruskal Wallis H test was applied, and the difference in concentration of TSH, FT3, FT4, Ferritin, anti-TPO amongst the three groups was found to be significant. The relationship between anti-TPO levels and serum ferritin concentration was further studied by multinomial logistic regression. We have found that there is a significant difference between the concentrations of ferritin; hence, it is highly likely that those with a high level of anti-TPO antibody shall have a higher concentration of serum ferritin. Conclusion: Ferritin concentrations were decreased in anti-TPO negative hypothyroidism, but in the case of anti-TPO positive hypothyroidism the ferritin concentrations are raised. Hence, hypothyroidism should not always be considered as an iron deficiency state.