RETROSPECTIVE EVALUATION OF DIAGNOSTIC METHODS AND TREATMENT OPTIONS IN AMIODARONE-INDUCED THYROTOXICOSIS

Objective: Amiodarone-induced thyrotoxicosis is an important cause of morbidity and mortality that is difficult for physicians to recognize and manage. We retrospectively analyzed the parameters used for diagnosis, classification, and treatment for amiodarone-induced thyrotoxicosis.Material and Method: We included patients who had amiodarone-induced thyrotoxicosis (AIT). We recorded the demographics, the presence and characteristics of heart and thyroid diseases, the time and dosage of amiodarone exposure, thyroid function tests and thyroid auto-antibodies, and the diagnostic methods and management of thyroid disease.Result: We included 25 patients (mean age: 64.1 & PLUSMN;15.3 years, 56% male) who were classified as type 1 (n:12; 48%), type 2 (n:7; 28%), and mixed-type amiodarone-induced thyrotoxicosis (AIT) (n:6; 24%). In the comparison of type 1 AIT to 2 AIT, free T3 and T4 concentrations were 5.1 & PLUSMN;1.6 pmol/L vs. 7.6 & PLUSMN;2.4 pmol/L, and 29.2 & PLUSMN;8.8 pmol/L vs. 34.9 & PLUSMN;11pmol/L, respectively. Iodine uptake measurement at the 2nd hours were positively correlated with the 24th-hour measurement (p=0.005). Antithyroid drug (n:20) was given for 24 months, glucocorticoid (n:7) and sodium perchlorate (n:5) were given for 7.4 & PLUSMN;1.7 and 3.5 & PLUSMN;2 months, respectively. The first treatment option was methimazole for type 1 AIT and methylprednisolone for type 2 AIT. The duration of remission was shorter in type 2 AIT (p=0.009). Five patients had radioactive iodine treatment, and one underwent thyroidectomy.Conclusion: The management of AITs is difficult. It should be kept in mind that these patients may need amiodarone again; therefore, ablative treatments should be planned if needed.