Pathological Characteristics of the Thyroid Gland in Patients with Triiodothyronine-Predominant Graves' Disease

Abstract

Pathology of the thyroid gland tissue was characterized in patients with Triiodothyronine (T3)-predominant Graves' disease who had normal levels of serum T4 but increased levels of serum T3 during antithyroid drug therapy. In order to compare this group of patients with an usual type of Graves' patients, age, sex, dietary intake of iodide, duration of antithyroid therapy and the dose of thionamide drugs were matched between the two groups of patients. Thyroid tissue was obtained from subtotal thyroidectomy. In examining the histology of the thyroid gland, integration eye piece plate II with regularly arranged 100 lattice points was set on eye lens of a microscope. The number of crossing points which were projected on each 4 histological elements was counted in randomly selected 10 fields of vision in each patient's thyroid. Assuming that the every histological element is arranged in a random manner, errors of each visual field by this method would be less than 12%. In consequence, the significant difference was demonstrated in the weight of subtotally resected thyroid and the ratio of each histological element except interstitial tissue occupied in the total thyroid tissue between T3-predominant Graves' disease and control Graves' disease. The volume composition of the epithelial cells and vacuoles in patients with T3-predominant Graves' disease was significantly greater than that of patients with control Graves' disease (24.7 +/- 10.6 vs 14.4 +/- 6.5%, 5.9 +/- 3.9 vs 2.0 +/- 1.0%, Mean +/- SD, respectively, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)