Serum thyroglobulin and its autoantibody following subtotal thyroid resection of Graves' disease

Abstract

Thyroid surgery leads to marked changes of the levels of serum thyroglobulin and its autoantibodies in the subsequent 3 postoperative weeks. Furthermore in Graves' disease progression of exophthalmos has sometimes been seen following thyroidectomy. Nineteen medically pretreated patients with Graves' disease and no signs of exophthalmos were studied systematically up to 6 months postoperatively. Nine patients had thyroglobulin antibodies. Mean values rose to 3.5 times pretreatment values within 2 months (P less than 0.001) followed by a gradual fall below pretreatment level after 6 months. None of the antibody negative patients reverted to positive or vice versa. Serum thyroglobulin (n = 10) was elevated preoperatively (mean 309 micrograms/l, SD 251), their values being normalized within 1-2 months (mean 19.4 micrograms/l, SD 7.3). The preoperative serum thyroglobulin correlated to the weight of the removed thyroid tissue (r = 0.87, P less than 0.01). Three patients showed elevated thyroid stimulating hormone after 1 month. Of these, two developed myxoedema, the third remained euthyroid with persistently elevated serum thyroglobulin. None showed recurrence or developed exophthalmos within the period of observation. In spite of rising levels of thyroglobulin antibodies in all patients with antibodies none developed exophthalmos and only one patient with thyroglobulin antibodies had clinical myxoedema.

Serum Thyroglobulin and Thyroglobulin Autoantibodies in Thyroid Diseases

“…But in some situations following thyroidectomy a combination of persistently increased levels of Tg and TSH with normal thyroid hormones can be seen (33,39). In these cases serum T g values may reflect a consistently increased intraglandular turnover of T g due to incipient failure of Tg synthesis in the thyroid glandular remnant.…”

“…In uztro experiments have shown that irradiation of lymphocytes without antigen availability may augment thyroid autoantibody production (69). However, an increase in serum TgAb concentration is also seen following subtotal thyroidectomy in Graves' disease (33,65). The increasing levels following both kinds of therapy have therefore been explained by release of antigen from the damaged thyroid gland and subsequent temporary change in the homeostatic control of the immune response (33).…”

“…However, an increase in serum TgAb concentration is also seen following subtotal thyroidectomy in Graves' disease (33,65). The increasing levels following both kinds of therapy have therefore been explained by release of antigen from the damaged thyroid gland and subsequent temporary change in the homeostatic control of the immune response (33). This theory is in accordance with experiments in mice giving evidence for initiation of an autoimmune response by existing self-reactive T and B cells on pronounced shifts in circulating T g levels (92).…”

REGRESSION OF OPHTHALMOPATHY IN GRAVES‘ DISEASE FOLLOWING THYROIDECTOMY A systematic study of changes of ocular signs

“…It is widely documented that surgical thyroidectomy for Graves' disease is followed by a decrease in serum concentrations of Tg, TgAb, and thyroid stimulating immunoglobulins (TSI) (Feldt-Rasmussen et al 1982;Bech et al 1982). Thus, some degree of immune remission seems to follow a reduction in thyroid mass.…”

Two Cases-Report of Mild Graves?Disease Following Subacute Thyroiditis: More Evidence of the Role of Thyroglobulin in The Pathogenesis of Autoimmune Thyroid Disease?

“…Iodinated peptides in Tg as well as iodine-induced apoptosis/necrosis of thyrocytes trigger autoimmune thyroid disease [25]. Increased release of Tg temporarily increases anti-Tg level, and has been reported after thyroid surgery [26], RAI administration [27], and ethanol administration in toxic adenomas [28,29]. In our cases, during the acute phase of SAT, serum Tg levels were increased, whereas anti-Tg was normal, which was followed by development of increased anti-Tg levels 3 months later, with the appearance of GD.…”