Basics of prevention and management of iodine-based contrast media-induced thyroid dysfunction - position paper by the Polish Society of Endocrinology.

Medical practice involves a high number of radiological examinations using iodinated contrast media (ICM). Therefore, it is crucial for doctors of different specialties to be aware of possible adverse effects associated with ICM use. The most common and well characterized adverse effect is contrast-induced nephropathy, whereas thyroidal adverse reactions remain a diagnostic and therapeutic dilemma. ICM-induced thyroid dysfunction represents a highly heterogenous group of thyroid disorders. Due to supraphysiological iodine concentration, ICM can induce both hyper- and hypothyroidism. In most cases, the ICM-induced thyroid dysfunction is oligo- or asymptomatic, mild, and transient. In rare cases, however, the ICM-induced thyroid dysfunction may be severe and life threatening. Recently, the European Thyroid Association (ETA) Guidelines for the Management of Iodine-Based Contrast Media-Induced Thyroid Dysfunction were published. The authors advise an individualized approach to prevention and treatment of ICM-induced thyroid dysfunction, based on patient's age, clinical symptoms, pre-existing thyroid diseases, coexisting morbidities, and iodine intake. There is a geographic variation of ICM-induced thyroid dysfunction prevalence, which is linked to iodine intake. The prevalence of ICM-induced hyperthyroidism, which may pose a serious therapeutic challenge, is greater in countries with iodine deficiency. Poland is a region with a history of iodine deficiency, contributing to an increased prevalence of nodular thyroid disease, especially in the elderly. Therefore, the Polish Society of Endocrinology has proposed national, simplified principles of ICM-induced thyroid dysfunction prevention and treatment.