Ankara Med J. 2021; 21(4): 687-700 | DOI: 10.5505/amj.2021.47542

Nonthyroidal Illness Syndrome

Buðra Durmuþ¹, Hüsniye Baþer², Bekir Çakýr^2
1Clinic of Endocrinology And Metabolism, Ankara City Hospital, Ankara, Turkey
²Department of Endocrinology And Metabolism, Yýldýrým Beyazýt University, Faculty of Medicine, Ankara, Turkey

Although the pathophysiology of thyroid hormone changes observed in acute or chronic diseases is not clearly understood, it has been known for about the last 50 years that the body has an adaptive metabolic response. On the other hand, it has also been shown in many studies that it can make inferences about the prognosis of the primary underlying disease. The most known of this thyroid hormone change pattern, defined as a non-thyroid disease, are low triiodothyronine (T3) and increased reverse T3 (rT3) levels. Although many pathogenetic mechanisms are thought to lead to these changes, the most known are changes in deiodinase activity, thyrotropin (TSH) secretion, and serum carrier proteins and/or cellular carrier receptors. Changes in thyroid hormones can vary at different stages of the primary underlying disease. In addition, in different clinical conditions or pathologies, thyroid hormones are affected in different ways, causing difficulty in the differential diagnosis. Many drugs used in the clinic are also known to affect thyroid hormones at different levels and directions. Current conditions should be taken into account when evaluating, and if possible, a full panel of thyroid hormones, especially TSH with free thyroxine (sT4), should be seen. The need for treatment should be decided by taking into account laboratory findings as well as the patient's clinical presentation and history. In many studies, routine thyroid hormone replacement is not recommended, as it does not give a positive or negative net result.

Keywords: Euthyroid sick syndrome, pathogenesis, differential diagnosis, treatment, prognosis

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Nontiroidal Hastalýk Sendromu

Buðra Durmuþ¹, Hüsniye Baþer², Bekir Çakýr^2
1Ankara Þehir Hastanesi, Endokrinoloji Ve Metabolizma Hastalýklarý Kliniði, Ankara
²Ankara Yýldýrým Beyazýt Üniversitesi Týp Fakültesi, Endokrinoloji Ve Metabolizma Hastalýklarý Bilim Dalý, Ankara

Akut veya kronik hastalýklarda görülen tiroid hormon deðiþimlerinin her ne kadar patofizyolojisi net anlaþýlmasa da vücudun metabolik olarak verdiði adaptif cevap olduðu yaklaþýk son 50 yýldýr bilinmektedir. Öte yandan primer altta yatan hastalýðýn prognozu ile ilgili çýkarýmlar yaptýrabileceði de birçok çalýþmada gösterilmiþtir. Nontiroidal hastalýk olarak tanýmlanan bu tiroid hormon deðiþim paterninin en bilinenleri düþük triiyodotironin (T3) ve artmýþ revers T3 (rT3) seviyeleridir. Birçok patogenetik mekanizmanýn bu deðiþimlere yol açtýðý düþünülse de en bilinenleri deiyodinaz aktivitesindeki, tirotropin (TSH) salgýlanmasýndaki ve serum taþýyýcý proteinlerinde ve/veya hücresel taþýyýcý reseptörlerindeki deðiþikliklerdir. Tiroid hormonlarýndaki deðiþimler primer altta yatan hastalýðýn farklý evrelerinde deðiþkenlik gösterebilir. Ayrýca farklý klinik durum ya da patolojilerde tiroid hormonlarý farklý þekillerde etkilenerek ayýrýcý taný güçlüðüne neden olabilir. Klinikte kullanýlan birçok ilacýn da tiroid hormonlarýný farklý düzeylerde ve yönlerde etkilediði bilinmektedir. Deðerlendirme yapýlýrken mevcut durumlar göz önünde bulundurulmalý ve mümkünse serbest tiroksin (sT4) ile TSH baþta olmak üzere tam tiroid hormon paneli görülmelidir. Tedavi gerekliliðine, laboratuvar bulgularý yanýnda hastanýn klinik prezentasyonu ve öyküsü de dikkate alýnarak karar verilmelidir. Yapýlan çok sayýda çalýþmada rutin tiroid hormon replasmaný, olumlu veya olumsuz yönde net sonuç vermediðinden önerilmemektedir.

Anahtar Kelimeler: Ötiroid hasta sendromu, patogenez, ayýrýcý taný, tedavi, prognoz

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