Thyrotoxicosis: an under-recognised aetiology

Abstract

A 53-year-old woman presented for evaluation of dizziness, shortness of breath and chest pain. She was found to be in atrial fibrillation with rapid ventricular response that was determined to be caused by iodine-induced thyrotoxicosis (from a CT scan with intravenous contrast 2 months prior to presentation). Jod-Basedow syndrome (iodine-induced hyperthyroidism) is infrequently considered as a cause of thyrotoxicosis, even when typical risk factors are present. However, this patient did not have typical risk factors: she did not reside in an iodine deficient area, did not have a prior diagnosis of thyroid disorder or goitre, had never been treated with thyroid medications or medications known to cause thyroid dysfunction and she presented later than is typical with this syndrome (2 months after receiving iodinated contrast). She had complete resolution of hyperthyroidism and atrial fibrillation 2 weeks later with no recurrence over the following 7 months.

Povidone-iodine-induced transient triiodothyronine thyrotoxicosis in a Japanese patient with prolonged habitual gargling: A case report and literature review

“…We reviewed the findings of thyroid scintigraphy and thyroid color Doppler ultrasonography in previously reported cases of iodine-induced hyperthyroidism in patients without a history of thyroid disease (Table 1). [3,7,[10][11][12][13][14][15][16][17][18] Although many reports describe decreased radioiodine intake, [10][11][12]16] radioiodine uptake varies widely in cases of amiodarone-induced hyperthyroidism type 1. [6] In iodine-induced hyperthyroidism, color Doppler thyroid ultrasonography generally shows increased blood flow [6,14] ; however, cases without increased blood flow also exist.…”

Iodinated Contrast-Induced Thyroid Storm With Concomitant Cardiac Tamponade: A Case Report

“…This phenomenon, known as Jod-Basedow syndrome, is a rare yet well-reported cause of thyrotoxicosis following the administration of exogenous iodine [13][14]. Iodine is an essential mineral that is necessary for proper thyroid function and hormone production, with any fluctuation in levels adversely affecting how well the thyroid functions [15][16].…”