[Amiodarone and antithyroid antibodies]

It is known proved that amiodarone, in chronic therapy, can cause side effects in several organs. The drug, because of its molecular structure and because of its iodine content, interferes with thyroid function and may produce ipo and hyperthyroidism. This should be related to the functional situation and to the autoregulatory mechanisms of the gland and to the iodine amount in the environment. Concerning the pathogenesis of these alterations, a controversy arose about autoimmune mechanisms and the significance which can be ascribed to the presence of circulatory antithyroid antibodies in amiodarone treated patients. In the present work the amount of antithyroid antibodies in a number of amiodarone treated patients has been related to the functional situation of the gland and to the period of treatment. The authors have studied 51 patients under short and long term therapy in comparison with a control group of 36 subjects. All the subjects under consideration live in Northwest Tuscany, an area where iodine intake is moderately low, therefore dysthyroidism and endemic goitre are rather frequent. No significant differences have been found about the amount of circulating antithyroid antibodies in the three groups under consideration.