Amiodarone-induced thyrotoxicosis suggestive of thyroid damage.

Amiodarone-induced thyrotoxicosis (AIT) is generally believed to result from increased hormonal synthesis related to the iodine overload. Thyroid damage has recently been incriminated as a pathophysiological mechanism. We report 3 cases of AIT associated with clinical and/or biochemical features consistent with thyroid damage. This hypothesis was supported by a painful thyroid (case 1), transient high serum Tg (case 2), a transient (case 2) or persistent (case 3) hypothyroid phase and an undetectable technetium thyroid uptake during the hypothyroid period (case 3). These clinical observations support the previous histological data indicating that thyroid follicular disruption might contribute to the pathogenesis of AIT.