[Diagnostics, treatment, and prevention of iatrogenic iodine-induced thyroid gland diseases]

The authors of the study investigated the effects of pharmacological doses of iodine as an ingredient of amiodaron, an anti-arrhythmic agent, and iodine radiopaque contrast agents (RCA), on the thyroid gland (TG) function. The subjects were 133 patients aged 60.5 +/- 8.5 years, who had been taking amiodaron for 12 to 164 months, and 164 patients aged 59.4 +/- 9.1 years, who were examined before coronarography (CAG) with RCA, and 1, 3, 6, and 12 months after the procedure. Serum levels of TSH, FT4, FT3, TG antibodies, TPO antibodies, and urine iodine level were measured; TG ultrasonography was performed. Forty-nine (51.9%) out of the 133 patients on amiodaron therapy developed thyroid disfunction. Subclinical hypothyroidism (24 cases; 18%) and manifest thyrotoxicosis (21 case; 15.8%) prevailed among functional TG disorders. Thirty-one per cent of the patients with thyrotoxicosis had preceding TG diseases; 70% of the thyrotoxicosis patients had a cardiac arrhythmia relapse. The concentration of thyroid antibodies did not change in patients with normal TG. The patients who underwent CAG displayed elevated renal iodine excretion 1, 3, and 6 months after RCA administration. Thyroid disfunction (thyrotoxicosis in 7.6% of the cases; hypothyroidism in 15.8% of cases) was revealed in 23.4% of the patients with preceding TG diseases one month after CAG. Cardial pathology exacerbation was observed in patients with thyrotoxicosis.