<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article  PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="research article"><front><journal-meta><journal-id journal-id-type="publisher-id">OJEMD</journal-id><journal-title-group><journal-title>Open Journal of Endocrine and Metabolic Diseases</journal-title></journal-title-group><issn pub-type="epub">2165-7424</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/ojemd.2024.142008</article-id><article-id pub-id-type="publisher-id">OJEMD-131320</article-id><article-categories><subj-group subj-group-type="heading"><subject>Articles</subject></subj-group><subj-group subj-group-type="Discipline-v2"><subject>Medicine&amp;Healthcare</subject></subj-group></article-categories><title-group><article-title>
 
 
  Letter to the Editor: Reverse T3; a Reliable Diagnostic Test for Discerning between Euthyroid Sick and Central Hypothyroidism
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Udaya</surname><given-names>M. Kabadi</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Sarah</surname><given-names>Exley</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref></contrib></contrib-group><aff id="aff1"><addr-line>Broadlawns Medical Center, Des Moines, Iowa</addr-line></aff><pub-date pub-type="epub"><day>30</day><month>01</month><year>2024</year></pub-date><volume>14</volume><issue>02</issue><fpage>73</fpage><lpage>74</lpage><history><date date-type="received"><day>19,</day>	<month>October</month>	<year>2023</year></date><date date-type="rev-recd"><day>23,</day>	<month>February</month>	<year>2024</year>	</date><date date-type="accepted"><day>26,</day>	<month>February</month>	<year>2024</year></date></history><permissions><copyright-statement>&#169; Copyright  2014 by authors and Scientific Research Publishing Inc. </copyright-statement><copyright-year>2014</copyright-year><license><license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p></license></permissions><abstract><p>
 
 
  Letter to the Editor
 
</p></abstract><kwd-group><kwd>&amp;nbsp;</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>Conflicts of Interest</title><p>The authors declare no conflicts of interest regarding the publication of this paper.</p></sec></body><back><ref-list><title>References</title><ref id="scirp.131320-ref1"><label>1</label><mixed-citation publication-type="other" xlink:type="simple">Goldstein, M., Islam, S., Piccione, J., Migasiuk, L. and Rothberger, G. (2022) Uitility of Thyroid Function Testing in Inpatient Setting. Endocrine Practice, 28, 853-858. https://doi.org/10.1016/j.eprac.2022.06.012</mixed-citation></ref><ref id="scirp.131320-ref2"><label>2</label><mixed-citation publication-type="other" xlink:type="simple">Sharma, S. and Kabadi, U. (2008) Euthyroid Sick Syndrome. Primary Care Reports, 14, 1-12.</mixed-citation></ref><ref id="scirp.131320-ref3"><label>3</label><mixed-citation publication-type="other" xlink:type="simple">De Groot, L. (2006) Non-Thyroidal Illness Syndrome Is a Manifestation of Hypothalamic-Pituitary Dysfunction, and in View of Current Evidence, Should Be Treated with Appropriate Replacement Therapies. Critical Care Clinics, 22, 57-86. https://doi.org/10.1016/j.ccc.2005.10.001</mixed-citation></ref><ref id="scirp.131320-ref4"><label>4</label><mixed-citation publication-type="other" xlink:type="simple">Kabadi, U. (2001) Thyrotropin Dysregulation during a Non-Thyroidal Illness: Transient Hypothalamic Hypothyroidism? Journal of Endocrinological Investigation, 24, 178-180. https://doi.org/10.1007/BF03343839</mixed-citation></ref><ref id="scirp.131320-ref5"><label>5</label><mixed-citation publication-type="other" xlink:type="simple">Exley, S., Banzal, S. and Kabadi, U. (2021) Low Reverse T3: A Reliable, Sensitive and Specific in Diagnosis of Central Hypothyroidism. Open Journal of Endocrine and Metabolic Diseases, 11, 137-143. https://doi.org/10.4236/ojemd.2021.117011</mixed-citation></ref></ref-list></back></article>