Endocrine Abstracts

Amiodarone is a widely used antiarhrythmic agent. Although life-threatening side effects of amiodarone therapy are well known, it’s not always possible to replace it with dronedarone. Some clinical trials showed that treatment with dronedarone led to significantly more unfavourable end-points (e.g. in congestive heart failure). Therapy of amiodarone induced thyrotoxicosis still raises many questions concerning optimal treatment choice to achieve euthyreosis as soon as possible. In our experience each case should be considered individually according to clinical course, comorbidities, etc.

Fourty patients (15 females, 25 males, mean age: 61 years) with severe amiodarone induced thyrotoxicosis were hospitalized in our Department between 2001 and 2011. 60% of them had life-threatening cardiological diseases. Mean FT₃ and FT₄ concentrations were respectively 13.3 pmol/l (n: 3.1–6.8) and 62.3 pmol/l – in nine patients FT₄ levels were >100 pmol/l (n 11–22).

Median time of hospitalization was 4 weeks (2–13 weeks), mean time of reaching euthyreosis – 14 weeks. Most common treatment was combined antithyroids and steroids iv. About a half of the patients were finally treated with I-131, after regaining iodine uptake. There were three deaths. One of the patients died because of severe heart arrhythmias. Another one, unresponsive to pharmacological treatment, was disqualified from thyroidectomy because he developed acute respiratory distress syndrome, underwent plasmaphereses, finally died of respiratory failure. The third one died due to massive gastric bleeding caused by hemorrhagic gastritis – complication of steroid treatment. However, in one of the patients, unresponsive to standard therapy, a thyroidectomy was successfully performed.

Conslusions: – Each patient with amiodarone induced thyrotoxicosis requires an individual approach.

– It’s substantial to determine the moment of radical treatment.

– Upon reaching euthyreosis it’s advisable to treat the patient with I-131 if further treatment with amiodarone is recommended.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.