Gökhan YILMAZ, Ece YİĞİT, Miraç PALA, Tuba MERT

SERUM SELENYUM SEVİYESİ DÜŞÜK SUBKLİNİK HİPOTİROİDİLİ HASTALARDA ORAL SELENYUM REPLASMAN TEDAVİSİNİN TSH ÜZERİNE ETKİLERİ

AMAÇ: Selenyum insan vücudunun önemli metabolik yolaklarının vazgeçilmez bir bileşenidir. Aktif bölgesine selenosistein şeklinde selenyum katılmış proteinler, selenoproteinler olarak tanımlanmaktadır ve bu proteinlerin fonksiyonlarını yerine getirmeleri için selenyuma gereksinimleri vardır. Selenyum elementi, Glutatyonperoksidaz (GPXs), Tioredoksinredüktaz (TRs) ve iyodotironindeiyodinaz (İD) gibi selenoproteinlerin yapısında bulunmaktadır. Selenoproteinler, tiroid hormon biyosentezine ve metabolizmasına, antioksidan savunma sisteminin kontrolüne katkı sağlamaktadır. Çalışmamızda subklinik hipotiroidisi olan otoimmün tiroidit hastalarına selenyum düşüklüğünün ne sıklıkla eşlik ettiğini ve selenyumu düşük olan hastalarda oral selenyum replasmanının tiroit stimülan hormon (TSH) üzerine etkilerini ortaya koymayı hedefledik.GEREÇ VE YÖNTEM: Çalışmamızda Aralık 2019 ile Temmuz 2020 aralığında 18 yaşından büyük olup polikliniğimize başvurmuş olan, asemptomatik subklinik hipotiroidisi olan 69 hastayı değerlendirdik. Serum selenyum düzeyi 80 μg/L’den düşük olan hastalara 3 ay süre ile yumuşak bir jel kapsül içinde oral yolla günde 83 mcg selenometiyonin verildi. Başka bir tedavi uygulanmadı. Üçüncü ayın sonunda tüm hastalarda serum tiroid hormon profiline ve selenyum seviyelerine bakıldı. Subklinik hipotiroidisi olan otoimmün tiroiditli hastaların, yüzdelik dilimler kullanılarak, oral selenyum replasmanı sonrası TSH seviyelerindeki değişiklikler gözlemlendi.BULGULAR: Çalışmamızda Aralık 2019 ile Temmuz 2020 arasında polikliniğimizde tespit edilen 69 asemptomatik subklinik hipotiroidisi olan hasta değerlendirildi. Çalışma kriterlerine uyumlu 43 hastanın 12 tanesinde (%28) serum selenyum düzeyi normal, 31 (%72) tanesinde serum selenyum düzeyi düşük (<80 μg/L) olarak tespit edildi. Üç ay boyunca günlük 83 mcg selenometiyonin oral selenyum replasman tedavisi verilen hastaların 19 (%61)’unda TSH değerinin normal sınırlar içerisine gerilediği görüldü (0,5mIU/L10.00 mIU/L) tespit edilirken, 9 (%29) hastada ise TSH değerinin halen 4.26 mIU/L- 10.00 mIU/L aralığında olduğu görülerek bu hastlara levotiroksin tedavisi başlandı.SONUÇ: Çalışmamızda selenyum eksikliği bulunan asemptomatik otoimmün subklinik hipotiroidi hastalarına oral selenyum replasmanı yaparak, serum TSH değerleri üzerindeki kısa dönem etkilerini değerlendirdik ve hastaların %61 inin 3 ay içerisinde ötiroid olduğunu gözlemledik. Selenyum eksikliğinin replase edilmesinin, teorik anlamda otoimmün tiroidit başta olmak üzere tüm otoimmün hastalıkların inflamatuar ve oksidatif hasar sürecine olan olumlu etkileri mevcuttur. Ancak bu konuda deneysel ve klinik prospektif planlanmış ve alt grupların detaylandırıldığı kapsamlı çalışmaların yapılması gerektiğini düşünüyoruz.

Anahtar Kelimeler:

Selenyum, Subklinik hipotiroidi, TSH.

EFFECTS OF ORAL SELENIUM REPLACEMENT ON TSH IN PATIENTS WITH SUBCLINIC HIPOTIROIDISM WITH LOW SERUM SELENIUM LEVELS

OBJECTIVE: Selenium is an essential component of important metabolic pathways of the human body. Proteins in which selenium is added to the active site in the form of selenocysteine are defined as selenoproteins and they require selenium to fulfill their functions. Glutathioneperoxidase (GPXs) is found in such selenoproteins as Thioredoxinreductase (TRs) and Iodothyroninedeiodinase (ID). Selenoproteins contribute to thyroid hormone biosynthesis and metabolism and the control of the antioxidant defence system. In our study, we aimed to reveal how often patients with subclinical hypothyroidism and autoimmune thyroiditis are accompanied by low serum selenium level and the effects of oral selenium replacement on Tiroit Stimulating Hormone (TSH) in patients with low selenium.MATERIAL AND METHODS: In our study, we evaluated 69 patients who were with asymptomatic subclinical hypothyroidism and aged older than 18 and who applied admitted to our outpatient/out-patient clinic between December 2019 and July 2020. Patients with serum selenium levels lower than 80 μg / L were given 83 mcg of selenomethionine in a soft gel capsule for 3 months. No other treatment was applied. At the end of the third month, serum thyroid hormone profile and selenium levels were measured in all patients. Changes in TSH levels were observed in patients with autoimmune thyroiditis with subclinical hypothyroidism after oral selenium replacement by using percentiles.RESULTS: In our study, 69 patients with asymptomatic subclinical hypothyroidism diagnosed in our outpatient clinic between December 2019 and July 2020 were evaluated. Serum selenium level was identified as normal in 12 (28%) of 43 patients, and serum selenium level was identified as low (<80 μg / L) in 31 (72%) patients. TSH values were found as regressed within normal limits (0,5mIU/L 10.00 mIU / L) in 3 (10%) patients, the TSH value was identified as still in the range of 4.26 mIU / L-10.00 mIU / L in 9 (29%) patients and levothyroxine treatment was started in these patients.CONCLUSIONS: In our study, we evaluated the short-term effects of oral selenium replacement in asymptomatic autoimmune subclinical hypothyroid patients with selenium deficiency, on serum TSH values and we observed that 61% of patients were euthyroid within 3 months. Replacing selenium deficiency has positive effects on the inflammatory and oxidative damage processes of all autoimmune diseases, especially autoimmune thyroiditis. However, we think that experimental and clinical comprehensive studies, which are detailed in sub-groups, should be conducted on this subject.

Keywords:

Selenium, Subclinical hypothyroidism, TSH.,

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