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

Abstract

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. 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. 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. 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.