Congenital hypothyroidism, cretinism, athyroidism, thyroid dysplasia, thyroidectopiaThe thyroid gland is a hormone-producing bilobed gland in the front part of the neck. Hypothyroidism occurs when the thyroid gland produces no or insufficient amounts of the thyroid hormones thyroxine and triiodidthyronine so that the hormone effect on the target organs is reduced or absent. The thyroid hormones increase the overall metabolism and promote growth and development.
Introduction
If the produced hormones are insufficiently produced, this is called hypothyroidism. The thyroid hormones stimulate our metabolism and increase the functions of circulation, growth and psyche. Hypothyroidism therefore reduces physical activity and keeps the metabolism at a low level. The hypothyroidism can cause unrecognized severe physical and mental developmental damage in adolescent children, which is why a mandatory test is carried out in Germany during the neonatal examination.
Frequency distribution
Hypothyroidism affects about 1% of the population, with women being affected more often than men. Congenital hypothyroidism occurs in 1 in 5000 newborns and is thus one of the most common congenital metabolic diseases.
Thyroid horns
The thyroid hormones L-tetraiodothyronine (T4), also called thyroxine, and L-triiodothyronine (T3) have various effects and sites of action. The release of thyroid hormones is controlled by a closed loop system. The hormone TRH (Thyrotropin Releasing Hormone) is released from the central nervous system and acts on the pituitary gland, which now produces more TSH (Thyroid Stimulating Hormone) and releases it into the blood.
TSH acts on the thyroid gland. The thyroid cells are stimulated to produce hormones, so that T3 and T4 are subsequently released. Outside the thyroid gland, T4 is converted into T3, which is the more active of the two hormones. The release of the thyroid hormones into the blood again causes, in the context of a feedback reaction in the control loop, that less TRH and thus TSH is released. The concentration of the thyroid hormones T3 and T4 present in the blood is the basis of this control cycle.