Importance of TSH in solitary nodule thyroid evaluation

  • A more useful assay is the high-sensitivity thyrotropin assay (TSH). This assay is the only test that is necessary to detect abnormalities in thyroid function. This high-sensitivity thyrotropin assay will pick up thyroid function abnormality before fluctuations in T4 can be detected. Most patients with thyroid nodules are euthyroid, and thus thyrotropin will most often be normal. When an abnormal thyrotropin result is identified, levels of T4 and T3 should be obtained. A reduced thyrotropin level may indicate hyperthyroidism, such as an autonomic functioning gland or thyrotoxicosis, whereas an elevated thyrotropin level indicates hypothyroidism or thyroiditis. In both of these situations, the gland can be enlarged or nodular