A Study of Thyroid Reserve in Hashimoto's Disease
1980 Volume 56 Issue 7 Pages 908-916
Details
1980 Volume 56 Issue 7 Pages 908-916
A three-day thyroid stimulating hormone (TSH) test of administering 10 U.S.P. bovine TSH intramuscularly was performed on 6 normal subjects, 14 patients with Hashimoto's disease and 6 patients with primary hypothyroidism. The response of 24hr thyroidal 131I-uptake (131I-uptake) and of serum thyroxine (T4) and triiodothyronine (T3) was studied in these subjects.
Of the 14 patients with Hashimoto's disease, T4, T3 and TSH were normal in 5 patients (group 1); both T4 and T3 were normal and TSH was high in 5 patients (group 2); and either both T4 and T3 or one of them was low and TSH was high in 4 patients (group 3). 131 I-uptake was normal in groups 1 and 2, and low in group 3.
The mean increase in 131I-uptake was 33.7±11.4% (S.D.) in normal subjects, 22.8±5.6% in group 1, 4.4±5.0 in group 2, and no change in group 3 and primary hypothyroidism.
The increase in T4 was 9.1-47.2pg/100ml in normal subjects, 3.7-6.1pg/100ml in group 1, 0-3.2μg/100ml in group 2, and no change in group 3 and primary hypothyroidism. The increase in T3 was 106-334ng/100ml in normal subjects, 38-140ng/100ml in group 1, 9-50ng/100ml in group 2, and no change in group 3 and primary hypothyroidism.
Group 2 proved to be in the so-called condition of “low thyroid reserve” because 131I-uptake, T4 and T3 though normal before the test, failed to respond to TSH-stimulation, and endogenous TSH was increased in this group.
In group 1,131 I-uptake responded to TSH-stimulation normally, but T4 and T3 did not. Group 1 seemed to be in the early stage of “low thyroid reserve”.
