Percutaneous ethanol injection therapy of autonomous nodule and amiodarone-induced thyrotoxicosis.

Abstract

A patient with amiodarone-induced thyrotoxicosis and autonomous nodule was treated with percutaneous ethanol injection (PEI) in 8 sessions. Preinjection thyroid hormone levels showed a marked elevation, peaking before the third session. The thyroid hormone increments following each procedure never exceeded 20% of the preinjection levels. FT4 plasma levels thereafter declined to within the normal range by the sixth session (day 21), while FT3 levels, though markedly reduced, were still slightly elevated; also, the thyroid hormone increments following ethanol injection were not observed after the fifth session. These findings suggest that a significant, but not sustained, increase in thyroid hormone levels is induced by PEI and may account for the lack of acute deterioration of clinical status, which remained under control with medical treatment alone. Normal serum thyroid hormone levels were observed at the 3 and 12 month follow-up. The use of percutaneous ethanol injection therapy for amiodarone-induced hyperthyroidism should be restricted to patients with preexisting thyroid hyperfunctioning nodule, and it may be a practical alternative to surgery in addition to medical treatment. Special caution should be exercised with patients with severe underlying heart disorders, since their clinical status might seriously worsen in case of acute elevations of serum thyroid hormones following ethanol injection. To this purpose, a close monitoring of serum thyroid hormones is recommended in order to institute a prompt adjustment in their medical therapy and/or in their PEI protocol.