Drug-induced thyrotoxicosis: the surgical option

Drug-induced thyrotoxicosis is not uncommon. It may worsen life-threatening arrhythmias and may be refractory to medical treatment. Near-total thyroidectomy presents a valid alternative to medical therapy and should be considered early in the management of the disease.

To assess whether near-total thyroidectomy was a viable approach for our patients.

Twelve patients--7 men and 5 women, aged 63 to 82 years--presented with drug-induced fulminant thyrotoxicosis following 1 to 12 months of amiodarone treatment (11 patients, mean 7 months) and after a 6 months course of interferon-alpha treatment (one patient). Medical therapy included propylthiouracil in doses up to 1200 mg/day in all patients and a beta-receptor antagonist in seven. Five patients had to stop amiodarone treatment and start high doses of steroids. A thyroid scan was performed in all patients using 5 mCi of Tc-99m pertechnetate. The thyroid scan showed absent uptake of the tracer in the thyroid bed in all patients, precluding the use of radioablation.

Four patients (three with AIT and one with interferon therapy) who did not respond to 3 months of medical therapy required surgical thyroidectomy due to severe unremitting thyrotoxicosis. A near-total thyroidectomy resulted in rapid correction of thyrotoxicosis, enabling continuation of the anti-arrhythmic drug. There were no intraoperative or postoperative arrhythmias. Subsequently, all patients recovered rapidly and remained well and euthyroid on thyroxine replacement therapy.

Since surgery results in rapid control of thyrotoxicosis and permits continued therapy with amiodarone, we suggest that near-total thyroidectomy warrants consideration as a definitive treatment for resistant amiodarone or interferon-induced thyrotoxicosis.