Serum TSH | Serum free T4 | Serum T3 | Assessment |
Normal | Normal | Normal | Euthyroid |
Normal hypothalamic-pituitary function | |||
Low | High (or normal) | High | Hyperthyroidism |
Normal | High | T3 toxicosis | |
High | Normal | T4 toxicosis | |
Low | Normal | Normal | Subclinical hyperthyroidism* |
Abnormal hypothalamic-pituitary function | |||
Normal or high | High | High | TSH-mediated hyperthyroidism |
Low¶ | Normal | Low or normal | Euthyroid with nonthyroidal illness or hyperthyroidism in a critically ill patient. Consider hyperthyroidism in a critically ill patient when TSH is lower¶ and free T4 and T3 are higher than expected in nonthyroidal illness*. |
TSH: thyroid-stimulating hormone; T4: thyroxine; T3: triiodothyronine.
* Euthyroid patients with nonthyroidal illness may have low serum TSH and low-normal or low free T4; T3 is usually low. Some patients with central hypothyroidism have low serum TSH and normal (but usually low-normal) or low free T4 and T3 concentrations.
¶ In critically ill hyperthyroid patients, the TSH is typically very low (eg, <0.01 mU/L). In contrast, detectable but subnormal TSH values (eg, 0.1 to 0.4 mU/L) are more consistent with nonthyroidal illness.آیا می خواهید مدیلیب را به صفحه اصلی خود اضافه کنید؟