Thyroid Function Tests - The UK Guidelines

[Guest guest]

For all of you members who have been tested for Free T3 - or had their FreeT3 request turned down by your local laboratory, perhaps you would bring to your doctors attention the following (if it means what I think it means).

This comes from the UK Guidelines for Thyroid Function Testing - http://www.british-thyroid-association.org/TFT_guideline_final_version_July_2006.pdfA strategy of first-line TSH may be cost effective for a wide range of clinical purposes including screening and case finding, but it may be inappropriate in patients being tested for the first time, and in some specific clinical settings. Throughout these guidelines we have highlighted the clinical situations where measurement of both serum TSH and FT4 is required; these are principally where the pituitary-thyroid axis is not intact or is unstable. These situations include relatively common situations such as optimising thyroxine therapy in newly diagnosed patients with hypothyroidism, diagnosing and monitoring thyroid disorders in pregnancy and monitoring patients with hyperthyroidism in the early months after treatment. Rare situations include diagnosis and monitoring treatment for central hypothyroidism, end-organ thyroid hormone resistance and TSH-secreting pituitary adenomas. It is the responsibility of the requesting physician to provide clinical information to guide the laboratory in the selection of the most appropriate TFT but if clinical details are not available that allow the identification of the above categories of patient, then it may be prudent for laboratories to measure serum TSH and FT4 on all specimens rather than embark on a first-line serum TSH testing strategy followed by a cascade to include FT4 and FT3 if indicated.

So, do I take this to mean that if our GP requests a Free T3 test on the pathology request form, because he needs to know whether his patient has a conversion problem, then the laboratory must test Free T3 - or am I reading this wrong?

Sheila