Role of Renal Anemia in the Functional, Morphological and Autoimmune Thyroid Disorders in patients on Chronic Hemodialysis

Abstract

Thyroid disorders are common in chronic kidney disease. The aim of this study was to examine the role of renal anemia on thyroid function, morphology and autoimmunity in clinically euthyroid patients on chronic hemodialysis (HD). Prospective study during 12 months period included 40 stable patients on chronic HD treatment. Patients were divided into two groups according to the serum hemoglobin level (group A Hgb > 125 g / L and group B Hgb < 125 g / L). Blood samples were taken for determination total and free thyroid hormones, thyroid antibodies and standard biochemical tests. Thyroid ultrasonography was performed with a 7.5 MHz transducer, 50 mm linear transducer. Thyroid volume was calculated, echostructure assessed and presence of nodular changes. In group A, was found significantly lower levels of total T3 (1.29 +/- 0469 vs. 1.55 +/- 0352, p < 0.1); higher prevalence of low T3 syndrome (17.24% (n = 5) vs. 0.00 (n = 0), p < 0.05); ultrasound findings suggestive for Hashimoto thyroiditis (13.79 (n = 4) vs. 0.00% (n = 0), p < 0.05) and multinodular goiter (13.79% (n = 4) vs. 0.00% (n = 0), p < 0.05). We found no statistically significant difference in the mean values of of thyroid antibodies levels, as well as in their percentage representation among groups. Morphological, functional and autoimmune disorders of thyroid gland are more common in patients on HD with Hgb level < 125 g/L. These findings suggest a role of renal anemia in the pathogenesis of these, and need for periodical screening of thyroid function, morphology, and titer of thyroid antibodies in patients HD, as well as more effective diagnosis and more aggressive treatment of renal anemia.