Thyroid dysfunction following a kelp-containing marketed diet. (29th October 2014)

• Record Type: Journal Article
• Authors: Di Matola, Tiziana; Zeppa, Pio; Gasperi, Maurizio; Vitale, Mario
• Is Part Of: BMJ case reports. Volume 2014
• Publication Date: 2014-10-29
• Subjects: Medicine -- Case studies -- Periodicals; 610.5
• DOI: 10.1136/bcr-2014-206330
• Languages: English
• ISSNs: 1757-790X

Abstract

Abstract : Complementary medications and herbal medicine for weight loss have become very popular. We report a case of thyroid dysfunction following the ingestion of a kelp-containing marketed diet in a 45-year-old woman with no previous thyroid disease. Signs of hyperthyroidism occurred shortly after a kelp-containing diet. Hyperthyroidism lasted 2 months and was followed by an overt hypothyroidism. The thyroid scintiscan exhibited an extremely low uptake and colour-Doppler ultrasonography revealed multiple small areas of pulsatile flow. After 3 months of levothyroxine substitutive therapy, normal thyroid function was recovered after levothyroxine discontinuation. This clinical history is compatible with a case of iodine-induced thyrotoxicosis followed by prolonged block of the sodium–iodide symporter activity as a consequence of excessive iodine consumption from kelp. Consumers of marketed diets containing kelp or other iodine-rich ingredients should be advised of the risk to develop a thyroid dysfunction also in the absence of underlying thyroid disease.