Serum thyroglobulin in patients with autonomous thyroid nodules.

Area of Science:

• Endocrinology
• Thyroidology
• Molecular Biology

Background:

• Thyroid hormones regulate metabolism.
• Thyroglobulin (TG) is a key protein in thyroid hormone synthesis and secretion.
• Autonomous thyroid nodules can disrupt normal thyroid function.

Purpose of the Study:

• To investigate the relationship between thyroid hormones and thyroglobulin (TG) secretion in patients with solitary autonomous thyroid nodules.
• To assess TG levels as an indicator of thyroid hyperfunction.

Main Methods:

• Measured total and free thyroid hormone levels, TSH, TRH response, and serum TG concentrations in 61 patients.
• Compared TG levels in patients with nodules to normal controls.
• Evaluated TG levels in 20 patients 6 months post-nodulectomy.

Main Results:

• Serum TG levels were significantly higher in patients with autonomous nodules than in controls.
• Elevated TG was observed even in patients with normal thyroid hormone levels.
• TG concentrations correlated with FT3 levels and were higher in patients with non-responsive TSH to TRH.
• Post-surgery, TG levels remained elevated, likely due to rebound TSH stimulation.

Conclusions:

• TG is secreted alongside thyroid hormones in autonomous nodules, independent of stimulatory actions.
• Serum TG is a sensitive marker of thyroid hyperfunction.
• Elevated postoperative TG levels are primarily attributed to TSH stimulation of normal thyroid tissue.