Freie Schilddrüsenhormone – Physiologie, Bestimmungsmethoden und Interpretation

Zusammenfassung

Aufgrund der Prävalenz von Schilddrüsenerkrankungen und des oft unspezifischen klinischen Beschwerdebildes bei Funktionsstörungen der Schilddrüse gehören die Schilddrüsenhormone mit zu den am häufigsten untersuchten Hormonen. Schilddrüsenhormone repräsentieren phylogenetisch alte Hormone, die Entwicklung und Stoffwechsel schon bei primitiven Lebensformen regulieren. In der Übersicht werden Grundlagen der Schilddrüsenhormonsynthese, Prinzipien der Hormonwirkung und Veränderungen der Schilddrüsenhormonkonzentrationen unter physiologischen und pathologischen Konditionen dargestellt. Möglichkeiten und Einschränkungen der zur Verfügung stehenden Bestimmungsmethoden und die klinische Interpretation der Messergebnisse werden diskutiert.

Abstract

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.

Schlüsselwörter

freie Schilddrüsenhormone - fT4 - fT3 - Hyperthyreose - Hypothyreose

Key words

free thyroid hormones - fT4 - fT3 - hyperthyroidism - thyrotoxicosis - hypothyroidism

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