Endocrine Abstracts

Background

Thyrotoxic crisis (TxC) is a medical emergency status needed rapid diagnostic a urgent treatment, presented by failure or multiorgan dysfunction. Amiodarone induced thyrotoxicosis (AIT) is one of the severe complications caused by amiodarone therapy.

Aim

Analysis of patients suffered from thyrotoxic crisis induced by Amiodarone therapy, with focus on clinical picture, laboratory findings and therapeutic options.

Methods and results

A total of 35 consecutive patients with AIT during the period 2005–2019 were included. We performed retrospective analysis of 4 consecutive patients with thyrotoxic crisis, who were hospitalized on department of Internal Medicine University Hospital Banska Bystrica. All of patients were men (mean age 55 ± 4.7 years), All of analysed patients (n = 4) have been treated for arterial hypertension, 25% (n = 1) ischaemic heart disease, 50% (n = 2) suffered from heart failure and 50% (n = 2) had implantable cardioverter defibrillator. Indication for Amiodarone therapy was atrial fibrillation (n = 2) and ventricular tachyarrhythmias (n = 2). The average time of use of amiodarone until development TxC was 937 ± 241 days, median 883 days. Mean TSH in the time of diagnosis was 0.007 ± 0.06 mIU/l and mean free T4 was 55.0 ± 16.1 pmol/l (median 59 pmol/l). Mean volume of thyroid gland was 22.21 ml. Three pacients have been diagnosed as mixed type AIT, and the one of threm as AIT type 2. All of patients (n = 4) have been treated with antithyroid drugs and corticosteroids at the maximum recommended doses. 75% (n = 3) underwent urgent thyroidectomy and one was threated conservatively. The thyroid papillary microadenocarcinoma was histologically confirmed in 1 of observed patients. When comparing the two cohorts with and withoud TxC, we found that patients with TxC are 8 years younger, have higher fT4, larger volume of thyroid. The dose and duration of Amiodarone use did not differ in both groups.

Conclusion

Thyrotoxic crisis induced by Amiodarone is an endocrine emergency which is charecterized by multiple organ failure due to sever thyrotoxicosis. Risk factors of thyrotoxic crisis development in patient with AIT are: younger age, higher fT4, larger volume of thyroid, atrial fibrillation and heart failure.