Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidism
Thyroid-stimulating hormone is generally regarded as a standard parameter for the evaluation of thyroid function. However, relying on this hormone alone can be misleading. Therefore, thyroxine/free-thyroxine levels are used in patients with levothyroxine substitution for the adjustment of therapy. E...
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| Format: | Article |
| Language: | English |
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Bioscientifica
2022-07-01
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| Series: | Endocrine Connections |
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| Online Access: | https://ec.bioscientifica.com/view/journals/ec/11/7/EC-22-0032.xml |
| _version_ | 1818006836287111168 |
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| author | Carmen Sydlik Ilja Dubinski Susanne Bechtold Heinrich Schmidt |
| author_facet | Carmen Sydlik Ilja Dubinski Susanne Bechtold Heinrich Schmidt |
| author_sort | Carmen Sydlik |
| collection | DOAJ |
| description | Thyroid-stimulating hormone is generally regarded as a standard parameter for the evaluation of thyroid function. However, relying on this hormone alone can be misleading. Therefore, thyroxine/free-thyroxine levels are used in patients with levothyroxine substitution for the adjustment of therapy. Even with normal values for free thyroxine, decreased values for the free-triiodothyronine/free-thyroxine ratio have already been described in adults. In this study, the free-triiodothyronine/free-thyroxine ratio of 25 children with congenital hypothyroidism was compared with 470 healthy children seen for other reasons and then for thyroid dysfunction. Mean free thyroxine in congenital hypothyroidism was just below the upper limit of normal and significantly higher than in control group. Mean values for free triiodothyronine showed no significant difference between the two groups. The mean value for the free triiodothyronine/free-thyroxine ratio in control group was 3.23. Significantly lower ratios were found in the congenital hypothyroidism group with a mean value of 2.5, due to higher values for free thyroxine compared to free triiodothyronine. Furthermore, an increased free triiodothyronine/free-thyroxine ratio was found at higher thyroid-stimulating hormone values due to lower values for free thyroxine. In this study, we demonstrate that the free triiodothyronine/free-thyroxine ratio was significantly lower in children with congenital hypothyroidism compared to the control group. This is most likely due to the higher values for free thyroxine in this group compared to similar values for free triiodothyronine in both groups. Further studies with differentiated thyroid hormone therapy are needed in order to understand the role of peripheral euthyroidism. |
| first_indexed | 2024-04-14T05:06:41Z |
| format | Article |
| id | doaj.art-8f18323340824b4b8a6d2f26bc57f87c |
| institution | Directory Open Access Journal |
| issn | 2049-3614 |
| language | English |
| last_indexed | 2024-04-14T05:06:41Z |
| publishDate | 2022-07-01 |
| publisher | Bioscientifica |
| record_format | Article |
| series | Endocrine Connections |
| spelling | doaj.art-8f18323340824b4b8a6d2f26bc57f87c2022-12-22T02:10:40ZengBioscientificaEndocrine Connections2049-36142022-07-0111717https://doi.org/10.1530/EC-22-0032Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidismCarmen Sydlik0Ilja Dubinski1Susanne Bechtold2Heinrich Schmidt3Division of Pediatric Endocrinology, Center for Pediatric and Adolescent Medicine Inn-Salzach-Rott, Altoetting, GermanyDivision of Pediatric Endocrinology, Dr. von Hauner Children's Hospital, University Hospital Munich, LMU Munich, Munich, GermanyDivision of Pediatric Endocrinology, Dr. von Hauner Children's Hospital, University Hospital Munich, LMU Munich, Munich, GermanyDivision of Pediatric Endocrinology, Dr. von Hauner Children's Hospital, University Hospital Munich, LMU Munich, Munich, GermanyThyroid-stimulating hormone is generally regarded as a standard parameter for the evaluation of thyroid function. However, relying on this hormone alone can be misleading. Therefore, thyroxine/free-thyroxine levels are used in patients with levothyroxine substitution for the adjustment of therapy. Even with normal values for free thyroxine, decreased values for the free-triiodothyronine/free-thyroxine ratio have already been described in adults. In this study, the free-triiodothyronine/free-thyroxine ratio of 25 children with congenital hypothyroidism was compared with 470 healthy children seen for other reasons and then for thyroid dysfunction. Mean free thyroxine in congenital hypothyroidism was just below the upper limit of normal and significantly higher than in control group. Mean values for free triiodothyronine showed no significant difference between the two groups. The mean value for the free triiodothyronine/free-thyroxine ratio in control group was 3.23. Significantly lower ratios were found in the congenital hypothyroidism group with a mean value of 2.5, due to higher values for free thyroxine compared to free triiodothyronine. Furthermore, an increased free triiodothyronine/free-thyroxine ratio was found at higher thyroid-stimulating hormone values due to lower values for free thyroxine. In this study, we demonstrate that the free triiodothyronine/free-thyroxine ratio was significantly lower in children with congenital hypothyroidism compared to the control group. This is most likely due to the higher values for free thyroxine in this group compared to similar values for free triiodothyronine in both groups. Further studies with differentiated thyroid hormone therapy are needed in order to understand the role of peripheral euthyroidism.https://ec.bioscientifica.com/view/journals/ec/11/7/EC-22-0032.xmlcongenital hypothyroidismfree triiodothyroninefree thyroxinelevothyroxine |
| spellingShingle | Carmen Sydlik Ilja Dubinski Susanne Bechtold Heinrich Schmidt Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidism Endocrine Connections congenital hypothyroidism free triiodothyronine free thyroxine levothyroxine |
| title | Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidism |
| title_full | Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidism |
| title_fullStr | Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidism |
| title_full_unstemmed | Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidism |
| title_short | Free triiodothyronine/free thyroxine ratio in children with congenital hypothyroidism |
| title_sort | free triiodothyronine free thyroxine ratio in children with congenital hypothyroidism |
| topic | congenital hypothyroidism free triiodothyronine free thyroxine levothyroxine |
| url | https://ec.bioscientifica.com/view/journals/ec/11/7/EC-22-0032.xml |
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