Histological Study of the Effect of Amiodarone on Thyroid Follicular Cells in Albino Rat and its Management Using Carbimazole with and without Prednisolone

Introduction: Amiodarone is increasingly used in a number of cardiac conditions but it has a significant side effect profile, which includes thyroid dysfunction. Aim of the Work: Was to study the toxic effect of amiodarone on thyroid gland and its management using carbimazole with and without prednisolone. Materials and Methods: 40 adult male albino rats were used and were divided into four groups, group A (control group), group B each animal was treated daily with 2.7 mg of amiodarone for three months, group C: Each animal was treated daily with 2.7 mg of amiodarone for three months then was given 1 mg of carbimazole in concomitant with amoidarone for another one month and group D: Each animal was treated daily with 2.7 mg of amiodarone for three months then was given 1 mg of carbimazole and 0.4 mg prednisolone in concomitant with amoidarone for another one month. At the appropriate times, thyroid glands were dissected and prepared for both light and electron microscopic studies. Results: LM study of thyroid gland treated with amiodarone exhibited changes ranged from normal pictures to irregular thyroid follicles with disrupted lining epithelium and marked cellular infiltration in-between. EM study showed irregular nuclei with chromatin condensation, dilatation of RER, increased lysosomes and inclusion bodies and vesiculation of cytoplasm. Addition of carbimazole reflected partial improvement while addition of both carbimazole and prednisolone exhibited marked improvement nearly of all the thyroid specimens. Coclusion: Amiodarone therapy induced thyroid toxicity which could be managed by addition of carbamazole and prednisolone to amiodarone.