1301 – SELco^® Tg 1 step

Highlights

• Use of thyroglobulin (Tg) as target antigen
• Quantitative determination of Tg in human serum
• Results expressed in ng/mL
• High diagnostic sensitivity and specificity
• High precision within the measurement range
• CE marked

Intended Purpose

The SELco® Tg 1 step is a quantitative radioimmunoassay for the determination of thyroglobulin (Tg) in human serum. The SELco® Tg 1 step aids in the diagnosis of thyroid disorders when used alongside other clinical and laboratory findings, providing accurate and reliable measurements to support patient management and monitoring. The immunoassay is designed for manual professional in vitro diagnostic use.

Diagnostic Relevance

Thyroglobulin (Tg), an iodine containing glycoprotein and precursor of the thyroid hormones thyroxine (T4) and triiodothyronine (T3), makes up a major part of thyroid colloid. The biosynthesis of Tg is regulated by thyrotropin, the only thyroid tissue that can produce, store and secrete Tg; Tg is thus organ- and tissue specific. This specificity is the main indication of the Tg determination in monitoring differentiated thyroid carcinoma, essential in the early detection and exclusion of metastases or tumour relapses. This indication is also used in the follow-up of radioiodine treatments.

Serum Tg measurements plays a major diagnostic role in the management of patients with differentiated thyroid carcinoma (DTC) after treatment; measurable and increasing serum Tg levels are an early and reliable indicator of persistent or recurrent disease. Additionally, serum Tg measurements can be useful in the diagnosis of neonatal hypothyroidism. In hyperthyroid adults undetectable serum Tg suggests thyrotoxicosis factitia.

Healthy individuals with benign thyroid diseases often show Tg values above the reference range. Clinicians also see elevated serum Tg levels in various non-malignant thyroid disorders, such as Hashimoto’s thyroiditis, Graves’ disease, and non-toxic diffuse goiter. In these conditions, Tg levels do not correlate with disease severity.

Publications

• Rössing et al., (2016) Serum thyroglobulin doubling time in progressive thyroid cancer