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Thyroglobulin (TG)

What is Thyroglobulin (Tg)?

Thyroglobulin (Tg) is a high-molecular-weight glycoprotein (approximately 660 kDa) produced in large amounts by thyrocytes, the functional cells of the thyroid gland. It is secreted into the lumen of thyroid follicles, where it plays a vital role in the synthesis of thyroid hormones T3 (triiodothyronine) and T4 (thyroxine).

Factors Influencing Thyroglobulin Production

The production of thyroglobulin is regulated by thyroid-stimulating hormone (TSH), a lack of intrathyroidal iodine, and the presence of thyroid-stimulating immunoglobulins. These factors promote increased synthesis and secretion of Tg, especially in individuals with underlying thyroid conditions.

Clinical Relevance of Elevated Tg Levels

Elevated levels of thyroglobulin may be found in several thyroid disorders, including:

Hashimoto’s thyroiditis

Graves’ disease

Thyroid adenoma

Thyroid carcinoma

In Slough and nearby areas, testing for Tg is particularly useful in patients presenting with thyroid-related symptoms to support early detection and management.

Diagnostic Use in Thyroid Disorders

Thyroglobulin testing is valuable in distinguishing between subacute thyroiditis and factitious thyrotoxicosis. In cases of congenital hypothyroidism, Tg levels can help determine whether the condition is due to complete thyroid agenesis, thyroid hypoplasia, or other structural abnormalities of the gland.

Post-Operative Monitoring in Thyroid Cancer Patients

The most important application of thyroglobulin testing is in the post-surgical follow-up of patients with differentiated thyroid carcinoma (DTC). Monitoring Tg levels can assist healthcare professionals in Slough in detecting recurrence or residual thyroid tissue after thyroidectomy.

Thyroid Health Screening in Slough

If you’re based in Slough or the surrounding Berkshire areas and have concerns about your thyroid function, thyroglobulin testing—alongside other thyroid profiles—can provide essential insights for diagnosis and ongoing management.

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