What are the effects of low thyroid stimulating hormone and high thyroglobulin?

Thyroid function is known as the most important function generator of the human body. The thyroid gland controls the health level of the whole body by secreting a hormone. Therefore, the normality of thyroid function is directly related to the health level of the body. The thyroid stimulating hormone secreted by the thyroid gland has a vital influence on the body. Let's take a look at the effects of low thyroid stimulating hormone and high thyroglobulin.

1. Abnormal function:

Due to the stimulation of TRAb, the Tg of almost all patients with Graves' hyperthyroidism is elevated. A few people have low or low serum Tg, which may return to normal after treatment of hyperthyroidism due to the influence of TGAb. In some refractory hyperthyroidism, even if T4 and T3 are normal, serum Tg remains at a high level. The relationship between serum Tg, TRAb and recurrence of hyperthyroidism is not very close. Tg reaches its peak on the first day after hyperthyroidism surgery and returns to normal after several months; after isotope treatment, Tg can remain elevated for 1 to 3 months.

The serum Tg of patients with Plummer hyperthyroidism, subacute thyroiditis, and painless thyroiditis is elevated, and exogenous thyroid hormone drugs cause low Tg in patients with hyperthyroidism.

2. Thyroglobulin differentiation carcinoma:

The serum Tg value before surgery for differentiated thyroid cancer is of no significance for diagnosis, because the blood Tg of patients with thyroid diseases other than thyroid cancer may also be elevated, while the blood Tg of patients with thyroid cancer may also be normal. The blood Tg level before surgery for differentiated thyroid cancer is positively correlated with the tumor size.

The biological half-life of Tg in the body is 65.2 h. It takes 5 to 10 days after thyroidectomy for Tg to be lower than 5 to 10 μg/L. Ronga et al. [6] retrospectively analyzed 334 patients with differentiated thyroid cancer. The first blood Tg level was measured 40 days after surgery, and the patients were followed up for 4 to 16 years with regular blood Tg and whole-body scans. Results Within 18 months after surgery, the first blood Tg value of 79 patients with tumor metastasis was significantly higher than that of patients without metastasis (258.9±31.1 vs. (15.9±19.6) μg/L, p<0.0001]. Therefore, positive blood Tg after surgery indicates 3. Tumor recurrence or metastasis:

For patients with differentiated thyroid cancer who have undergone total thyroidectomy and received high-dose 131I treatment, if their serum TGAb is negative, their serum Tg should be undetectable. If serum TSH is in a suppressed state, elevated serum Tg often indicates the presence of residual tumor tissue or metastases. After total thyroidectomy for papillary thyroid cancer and follicular thyroid cancer, blood Tg should be <10μg/L. If it is >10μg/L, it indicates the possibility of metastasis. The sensitivity of this diagnosis is 100% and the specificity is over 80%. Negative Tg determination can reduce unnecessary whole-body 131I scans during follow-up.