Elevated Free T4
April 24th, 2019
Overview
Elevated T4 with suppressed TSH is suggestive of primary hyperthyroidism, while a normal or elevated TSH may be present with certain conditions or due to false elevation.
Causes of Elevated Free T4
Reduced TSH
- Primary hyperthyroidism
Normal / Elevated TSH
- TSH secreting pituitary tumour
- Thyroid hormone resistance
- Acute psychiatric illness
- Amiodarone
False Elevation
- Reduced TBG - androgens, glucocorticoids
- Familial dysalbuminaemic hyperthyroxinaemia
- Heterophile antibodies
- Heparin
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