Journal of Endocrinology and Metabolism, ISSN 1923-2861 print, 1923-287X online, Open Access
Article copyright, the authors; Journal compilation copyright, J Endocrinol Metab and Elmer Press Inc
Journal website

Case Report

Volume 5, Number 3, June 2015, pages 220-223

Mixed Amiodarone-Induced Thyrotoxicosis Refractory to Medical Therapy and Plasmapheresis


Figure 1.
Figure 1. Thyroid gland histopathology demonstrates intra-follicular histiocytes, patchy fibrosis and involuted follicles.


Table 1. The Trend of Thyroid Profile During the Hospital Stay
Hormonal investigationsOn presentationAfter 8 cycles of plasmapheresis24 h post-surgery72 h post-surgeryReference range
TSH (μIU/mL) tested0.28 - 3.89
Free T4 (ng/dL)4.884.543.251.720.58 - 1.64
Free T3 (pg/mL) - 3.9
Total T3 (ng/dL)114111672.187 - 178


Table 2. Characteristics of the Different Types of Amiodarone-Induced Thyrotoxicosis (AIT)
Features of AITType 1 AITType 2 AITMixed AIT
MechanismExcess thyroid hormone synthesisExcess release of T3, T4 (destructive thyroiditis)Features of both
Predisposed thyroid glandAbnormalApparently normal or small goiterFeatures of both
I-123 uptake scanMost commonly low or low-normal, but sometimes normal or increasedUsually very lowFeatures of both
Thyroid ultrasoundHyper-vascularityAbsent or decreased vascularityFeatures of both
Rare need to add potassium perchlorate (not FDA approved)
Anti-inflammatory therapy like prednisoneCombination of both