Table of Contents Author Guidelines Submit a Manuscript
Case Reports in Endocrinology
Volume 2017, Article ID 2683120, 4 pages
https://doi.org/10.1155/2017/2683120
Case Report

Severe Thyrotoxicosis Secondary to Povidone-Iodine from Peritoneal Dialysis

Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada

Correspondence should be addressed to Kirstie Lithgow; ac.sha@woghtil.eitsrik

Received 14 June 2017; Accepted 27 July 2017; Published 24 August 2017

Academic Editor: Osamu Isozaki

Copyright © 2017 Kirstie Lithgow and Christopher Symonds. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A 73-year-old male on home peritoneal dialysis (PD) with recent diagnosis of atrial fibrillation presented with fatigue and dyspnea. Hyperthyroidism was diagnosed with TSH < 0.01 mIU/L and FT4 > 100 pmol/L. He had no personal or family history of thyroid disease. There had been no exposures to CT contrast, amiodarone, or iodine. Technetium thyroid scan showed diffusely decreased uptake. He was discharged with a presumptive diagnosis of thyroiditis. Three weeks later, he had deteriorated clinically. Possible iodine sources were again reviewed, and it was determined that povidone-iodine solution was used with each PD cycle. Methimazole 25 mg daily was initiated; however, he had difficulty tolerating the medication and continued to clinically deteriorate. He was readmitted to hospital where methimazole was restarted at 20 mg bid with high dose prednisone 25 mg and daily plasma exchange (PLEX) therapy. Biochemical improvement was observed with FT4 dropping to 48.5 pmol/L by day 10, but FT4 rebounded to 67.8 pmol/L after PLEX was discontinued. PLEX was restarted and thyroidectomy was performed. Pathology revealed nodular hyperplasia with no evidence of thyroiditis. Preoperative plasma iodine levels were greater than 5 times the upper limit of normal range. We hypothesize that the patient had underlying autonomous thyroid hormone production exacerbated by exogenous iodine exposure from a previously unreported PD-related source.