Freie Schilddrüsenhormone – Physiologie, Bestimmungsmethoden und Interpretation

The high prevalence of thyroid diseases with often unspecific clinical symptoms causes the frequent request of laboratory tests for thyroid hormones. Thyroid hormones represent phylogenetically old hormones for the regulation of development and metabolism even in primitive life forms. The article summarizes the principles of thyroid hormone syntheses and hormone effects as well as physiologic and pathologic conditions that affect the homeostasis of thyroid hormones. The principles and limitations of current test assays and the clinical interpretation of the test results are discussed.