Thyroid-specific antigens and hormones

Calcitonin

Clinical significance

Calcitonin is a peptide hormone that is involved in regulating the calcium level and is produced in the parafollicular cells of the thyroid gland (C cells). Its production is stimulated by a raised calcium level or gastrointestinal hormones, e.g. pentagastrin. Calcitonin inhibits osteoclast activity and decreases the calcium concentration in the blood. Low Calcitonin levels are associated with osteopenia, a preliminary stage of osteoporosis, which is why calcitonin is among the substances given in osteoporosis therapy.

Diagnostics

Calcitonin serodiagnostics is generally indicated for clarification of scintigraphically cold thyroid nodules, therapy-resistant diarrhoea and unexplainable increase in the CEA value (carcinoembryonic antigen). Furthermore, determination of the calcitonin level in blood is required in paraneoplastic or reactive hypercalcaemia and for monitoring and relapse monitoring following surgical removal of C-cell carcinoma.

ProductOrder number
Calcitonin ELISAEQ 6431

Reverse triiodothyronine

Clinical significance

The biologically active metabolite reverse triiodothyronine (rT3) is created during impaired conversion of tetraiodothyronine (T4) to triiodothyronine (T3).

Diagnostics

Low T3 syndrome (euthyroid sick syndrome, non-thyroidal illness) is characterised by a disturbed homeostasis of thyroid hormones. This results in an accumulation of the inactive metabolite rT3, a normal to low TSH level, a low FT3 level and, with a long disease duration, a low FT4 level. The determination of rT3 can be useful to differentiate between patients with central hypothyroidism and patients with low T3 syndrome.

ProductOrder number
Reverse triiodthyronine(RT3) ELISAEQ 1016-9

Thyroid-specific antigens and hormones

RIA for the thyroid diagnostic
  • Specific detection of the thyroid antigen thyroglobulin and the hormones free triiodothyronine (FT3), free thyroxine (FT4), thyrotropin (TSH), calcitonin.
  • Indications: Medullary thyroid carcinoma, thyroidal C-cell hyperplasia, therapy controls in hyper- and hypothyrosis.
  • Serum undiluted.
  • 6-point to 8-point calibration (quantitative).

ProductOrder number
Thyroglobulin RIARD 1013
    FT3 RIARD 1016
    FT4 RIARD 1017
    TSH RIARD 1018-1
    Calcitonin RIARD 1019