Sidebar. Causes of Subclinical Hyperthyroidism (or Low Serum TSH Level).
Origin | Condition |
---|---|
Endogenous | |
Persistent | Toxic Adenoma |
Toxic Multinodular Goiter | |
Graves' disease | |
Pituitary disease (Central hypothyroidism) a | |
Transient | Subacute thyroiditis |
Silent thyroiditis | |
Postpartum thyroiditis | |
Euthyroid Sick Syndrome | |
Initial post-therapy period after treatment for overt hyperthyroidism | |
Other | Pregnancy (especially during the first trimester) |
Exogenous | |
Iatrogenic | Overtreatment with levothyroxine (most common cause) |
Factitial thyrotoxicosis (surreptitious levothyroxine intake) | |
Drug-induced thyroiditis (amiodarone, α-IFN) | |
Iodide excess (radiographic contrasts) | |
TSH-lowering medications (steroids, dopamine) |
aUsually associated with low Thyroxin and low Triiodothyronine