- Nonthyroidal Illness
- Amiodarone and Thyroid Disease
- Thyroid Cancer
|Common Diagnostic Tests in Thyroid Disorders|
|Thyroid-stimulating hormone (TSH)||Most sensitive test to detect 1° hypo- and hyperthyroidism.
Used as primary screening test for thyroid disease.
↓’d by dopamine, glucocorticoids, severe illness.
May not be accurate in central hypothyroidism.
|Free T4 (fT4)||Unbound T4, not influenced by TBG. Checked in a variety of thyroid states including hyperthyroidism & central hypothyroidism|
|Total T3||Total serum concentrations of T3 (liothyronine). Useful when evaluating for hyperthyroidism.|
|Antithyroid peroxidase Ab (anti-TPO)||Antithyroid peroxidase (TPO) seen in s (high titer), painless subacute thyroiditis and Graves’ disease (low titer)|