A Mass Spectrometry-Based Panel of Nine Thyroid Hormone Metabolites in Human Serum

[helvella]

This looks to be an interesting overview of the thyroid hormone metabolites (THM).

Probably well worth a brief overview even if much of it is above our heads.

On the basis that a large proportion of the medical establishment refuses to consider FT3, or even FT4 much of the time, what hope does anyone have of them recognising the other seven THMs?

A Mass Spectrometry-Based Panel of Nine Thyroid Hormone Metabolites in Human Serum

Rutchanna M S Jongejan, Theo Klein, Marcel E Meima, W Edward Visser, Ramona E A van Heerebeek, Theo M Luider, Robin P Peeters, Yolanda B de Rijke

Clinical Chemistry, hvaa022, doi.org/10.1093/clinchem/hv...

Published: 03 March 2020

Abstract

Background

While thyroxine (T4), 3,3’,5-triiodothyronine (T3), and 3,3’,5’-triiodothyronine (rT3) have routine methods available for evaluating patients with suspected thyroid disease, appropriate methods for the measurement of other thyroid hormone metabolites (THMs) are lacking. The effects of other iodothyronines or iodothyroacetic acids are therefore less explored. To better understand the (patho)physiological role of THMs, a robust method to measure iodothyronines and iodothyroacetic acids in serum in a single analysis is needed, including associated reference intervals.

Methods

Clinical and Laboratory Standards Institute guidelines, European Medicines Agency guidelines, and the National Institute of Standards and Technology protocol were used for the method validation and reference intervals. Reference intervals were determined in 132 healthy males and 121 healthy females. Serum samples were deproteinized with acetonitrile, followed by anion-exchange solid phase extraction and analysis with LC-MS/MS, using eight 13C6-internal standards

Results

The analytical method validation was performed for all nine THMs. Reference intervals (2.5th to 97.5th percentile) were determined for L-thyronine (4.9–11.3 ng/dL), 3-monoiodothyronine (0.06 --0.41 ng/dL), 3,5-diiodothyronine (<0.13 ng/dL), 3,3’-diiodothyronine (0.25--0.77 ng/dL), T3 (66.4--129.9 ng/dL), rT3 (15.0--64.1 ng/dL), T4 (4.3--10.0 µg/dL), triac/3,3’,5-triiodothyroacetic acid (not detected), and tetrac/3,3’,5,5’-tetraiodothyroacetic acid (2.2--27.2 ng/dL).

Conclusions

A broad dynamic concentration range exists among the nine THMs. This method should help to develop a better understanding of the clinical relevance of other THMs, as well as an understanding of thyroid hormone metabolism in health and disease.

Iodothyronines, iodothyroacetic acids, thyroxine, triac, tetrac, mass spectrometry, reference interval

Full paper freely accessible here:

academic.oup.com/clinchem/a...

[helvella Administrator Thyroid UK]

I am sorry that this post has not received an answer.

Replying to this post in order to stop it continuing to appear unanswered.

[tattybogle in reply to helvella]

Nurse ! .. Helvella's talking to a metabolite of his former self again ........

[radd in reply to tattybogle]

🤣