| Kahaly, Mainz, Germany, prospectively studied (double-blind, randomly) thyroid volume, 24hr iodine urinary excretion, thyroid function parameters and thyroid autoantibodies in two groups of patients with a mean iodine 24hr excretion of 47 µg and 32 µg. Gr I received 200 µg iodine daily, whereas the other group received placebo. Although, as expected, the iodine treated group showed a decrease in thyroid volume after 12 months of treatment (25.6 versus 17.6 ml) and when treatment was continued, the decrease persisted until end of follow-up at 6 months, high antibodies titres developed in 9.7 % of patients and hypothyroidism and hyperthyroidism developed in 2 and 1 patient(s) respectively during treatment. These abnormalities subsided after treatment was stopped. It is concluded that low-dose iodine therapy successfully normalizes thyroid volume, but that thyroid dysfunction and autoimmune phenomena may develop during iodine supplementation. |
