Robotics
Active Member
I think this is an important discussion point that is not talked about when trying to dial in our thyroids. What are your thoughts/discoveries on this?
How reliable are free thyroid and total T3 hormone assays?
"Measurement of T3, FT3, and FT4 by the immunoassay methods commonly used by the majority of laboratories is problematic, especially for low levels of thyroid hormones. A significant number of patients are misclassified as having normal levels of thyroid hormones when they actually have levels below the reference range by LC-MSMS. There are approximately 19 million patients with hypothyroidism in the United States alone. The misclassification of patients by a commonly used laboratory strategy thus has the potential to adversely impact a substantial number of patients. Laboratory assays are expected to be accurate over the entire analytical range, especially at the high or low end of the range where clinical decision points are often made. Assays for TT3, FT3, and FT4 should correlate with both log TSH and the patient’s clinical condition, which is not achieved on any of the commercially available FDA approved immunoassay platforms. LC-MSMS provides better correlation with these parameters over the entire analytical range. We suggest evaluation of patients employing LC-MSMS measurement of thyroid hormones when they continue to report symptoms of hypothyroidism despite therapy with LT-4. This approach may aid in identification of patients who may benefit from combination treatment with LT-3 and LT-4."
How reliable are free thyroid and total T3 hormone assays?
"Measurement of T3, FT3, and FT4 by the immunoassay methods commonly used by the majority of laboratories is problematic, especially for low levels of thyroid hormones. A significant number of patients are misclassified as having normal levels of thyroid hormones when they actually have levels below the reference range by LC-MSMS. There are approximately 19 million patients with hypothyroidism in the United States alone. The misclassification of patients by a commonly used laboratory strategy thus has the potential to adversely impact a substantial number of patients. Laboratory assays are expected to be accurate over the entire analytical range, especially at the high or low end of the range where clinical decision points are often made. Assays for TT3, FT3, and FT4 should correlate with both log TSH and the patient’s clinical condition, which is not achieved on any of the commercially available FDA approved immunoassay platforms. LC-MSMS provides better correlation with these parameters over the entire analytical range. We suggest evaluation of patients employing LC-MSMS measurement of thyroid hormones when they continue to report symptoms of hypothyroidism despite therapy with LT-4. This approach may aid in identification of patients who may benefit from combination treatment with LT-3 and LT-4."
