Thyroid

If a thyroid disease is suspected, the metabolic status of the thyroid gland must first be determined and the thyroid values ​​TSH and the free T3 and T4 (fT3, fT4) in the blood measured. These values ​​indicate whether there is a (latent) hyperthyroidism or hyperthyroidism. If the thyroid is underactive, the thyroid growth hormone TSH increases so that more thyroid hormones T3 and T4 are produced. With an overactive thyroid, there is too much fT3 and fT4 in the blood. As a result, there is a reduction in TSH production. In order to make a further specification of the disease, thyroid antibodies are determined from the blood.

Depending on the antibody profile, a distinction is made between the following autoimmune diseases:

• Hashimotothyroiditis
• Basedow's disease
• Subacute Thyroiditis DeQuervain
• Acute Thyroiditis

Thyroglobulin can be increased in the case of an inflammation of the thyroid gland or with larger nodular goiter Thyroglobulin (TG) is also a tumor marker. After total removal (thyroidectomy) of the thyroid gland, there should be no more TG in the blood. The detection of TG proves the presence of residual tissue or the regrowth of a differentiated thyroid carcinoma (papillary or follicular thyroid carcinoma). TG is therefore excellently suited as a tumor marker after total thyroidectomy. In the course of the follow-up after removal of a (differentiated) thyroid carcinoma, the anti-TG values ​​should also be determined. With high anti-TG levels, a low TG value with regard to freedom from tumors is not reliable. The thyroglobulin antibodies (anti-TG) can also be increased in Hashimotothyroditis. Autoantibodies against thyroid peroxidase (TPO-AK) are increased in over 90% of patients with hasimotothyroiditis, but also in patients with Graves' disease. In Graves disease, autoantibodies against the TSH receptor (TRAK) are typically found in the blood.

In addition to the physical examination (palpation of the neck) and the determination of the thyroid values, the ultrasound examination of the thyroid is to be carried out as a basic examination. The ultrasound can be used to document the size of the thyroid gland, any existing side differences and the echogenicity of the thyroid tissue itself.

If nodes are diagnosed in the thyroid gland, echogenicity is an important first parameter in the assessment: Echo-rich nodes are usually to be rated as harmless. Hypoechoic nodules or microcalcifications are signs of possible degeneration and require further clarification. If nodules are found in the ultrasound, a correlation with a scintigraphy must be carried out regardless of their echogenicity. Here the storage behavior of the nodes can be determined and a distinction is made between normally storing nodes, cold, (warm) and hot nodes.

This study is based on the principle that iodine ingested with food is built into the thyroid gland. This fact is now being used and weakly radioactively labeled iodine is administered into the vein. The iodine is absorbed into the thyroid gland and the distribution of the marked iodine in the thyroid gland is mapped with a special camera (gamma camera). This enables storage deficits (cold nodes) and areas with higher storage (hot nodes) or homogeneous storage to be distinguished.

With the results of ultrasound, scintigraphy and thyroid values ​​from the blood, one has a fairly precise impression of which disease is present and which further steps or which type of therapy is indicated. A fine needle aspiration or fine needle aspiration can provide additional information on suspicious nodules about their biological behavior or about their benign—malignant or benign—malignant status.