Repercusiones del tratamiento con amiodarona sobre la función tiroidea y su manejo actual

The prevalence of amiodarone-induced thyrotoxicosis (AIT) is between 1 and 23%. Two different clinical forms have been described with therapeutic and prognostic implications: type 1 AIT (iodine-induced thyrotoxicosis) and type 2 AIT (drug-induced destructive thyroiditis). Diagnosis of AIT is established by elevations of free T4 and free T3 with suppression of TSH serum concentrations and clinical symptoms of hyperthyroidism. Color flow Doppler sonography is the most effective procedure to discriminate AIT type 1 from type 2. In patients with AIT, amiodarone therapy should be withdrawn, when feasible, as in the case of non-life-threatening arrhythmias. Type 1 AIT is controlled with antithyroid drugs alone or in combination with potassium perchlorate. Type 2 AIT usually responds to steroids. In mixed forms, triple therapy (antithyroid drugs, steroids and potassium perchlorate) is recommended. Thyroidectomy is an appropriate therapeutic alternative in patients with AIT refractory to medical therapy.