What are the effects of routine thyroid gland palpation on serum thyroid hormone levels?
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July 2010Background: The assessment of serum thyroid hormone levels in association with thyroid palpation is widely used for the diagnosis of thyroid gland pathologies, often with blood sampling for thyroid function taking place after physical examination. While previous studies have shown that external trauma might cause variations in serum thyroid hormone levels, the effect of thyroid palpation is unknown.
Study design: Prospective study.
Setting: Haydarpa Numune Research and Education Hospital, Istanbul, Turkey.
Synopsis: Twenty adults with a diagnosis of nodular thyroid disease and 30 healthy subjects had their thyroid glands palpated by the same physician. Blood samples were obtained both before and two hours after thyroid gland palpation. The researchers found that routine palpation in both the patients with nodular thyroid disease and healthy individuals caused a significant increase in serum levels after palpation. Differences in TSH and TT4 levels were not significant in either group. The authors said their results indicate that palpation might cause a transient increase in thyroid hormone levels with high levels due only to the effects of palpation. Therefore, misleading reports of hormone levels might lead to misdiagnosis and mismanagement of patients. Additionally, the authors said that in patients with previously unknown raised levels of thyroid hormones, palpation might aggravate the disease process. In their discussion, the researchers noted previous studies involving increased serum levels. One study they mentioned, by Lever and colleagues, found that external manual palpation did not influence serum TG levels, but surgical palpation and FNAB resulted in elevations of serum TG.
Bottom line: The data suggest an effect of routine thyroid gland palpitation on serum thyroid hormone levels and suggest that serum thyroid hormone measurements should be performed before any manipulation of the gland, including palpation, to avoid misdiagnosis.
Citation: Toros SZ, Ozel L, Yekrek MM, et al. Does thyroid gland examination by palpation alter serum hormone levels? Laryngoscope. 2010;120(7):1322-1325.
—Reviewed by Sue Pondrom