Iodinated Compound and Thyroid Status

Among the many exciting developments in the study of the behavior of contrast media [4], little attention has been paid to the suggested correlation of the iodinated agents with thyroid hormone physiology. To what extent could the accumulation of iodinated drugs influence the thyroid metabolism? Although some data indicate that minimal absorption of free iodine generally occurs [3], we have not yet elucidated the interrelationship of the absorption, distribution, binding, and biotransformation of the amount of iodide contained in an ordinary contrast media dose. During the recent past years few studies have reported certain changes in circulating iodo-thyronines in several groups of subjects given different contrast media [1, 5]. A better insight of hormonal status could be achieved with the measurements of free fractions of thyroid hormones. We therefore decided to carry out a prospective study of the hormonal trends during the 3 months after contrast media administration.