Hyperthyroidism laboratory findings

Hyperthyroidism Microchapters
Patient Information
Overview
Classification
Differentiating hyperthyroidism from other diseases
Pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Laboratory findings

A diagnosis is suspected through blood tests, by measuring the level of thyroid-stimulating hormone (TSH) in the blood. A low TSH (the job of TSH taken over by thyroid-stimulating immunoglobulin [TSI] that act like TSH) indicates increased levels of T4 and/or T3 in the blood. Measuring specific antibodies, such as anti-TSH-receptor antibodies in Graves' disease, may contribute to the diagnosis. In all patients with hyperthyroxinemia, scintigraphy is required in order to distinguish true hyperthyroidism from thyroiditis.