32 Haftanın Altında Doğan Prematüre Bebeklerde Tiroid Fonksiyon Bozukluklarının Değerlendirilmesi

Öz

Amaç: Tiroid hormonları normal beyin gelişimi için kritik öneme sahiptir. Prematüre bebeklerde, tiroid bezinin yeterince gelişmemiş olması, hipotalamo-hipofizer-tiroid aksın immatüritesi, maternal tiroid hastalıkları, kullanılan ilaçlar ve prematüriteye bağlı morbiditeler nedeniyle tiroid fonksiyon bozuklukları sık görülmektedir. Bu çalışmada, Yenidoğan Yoğun Bakım Ünitesi’nde (YYBÜ) izlenen, 32. gebelik haftasının altında doğan prematüre bebeklerde tekrarlanan tiroid fonksiyon testlerinin (TFT) sonuçlarının değerlendirilmesi ve bu sonuçları etkileyebilecek olası faktörlerin araştırılması amaçlanmıştır. Gereç ve Yöntem: Çalışma grubunu, 2016–2021 yılları arasında Eskişehir Osmangazi Üniversitesi Tıp Fakültesi Hastanesi YYBÜ’de izlenen, gebelik yaşı 32 haftanın altında olan 250 prematüre bebek oluşturdu. Prematüre bebeklere ait veriler hastane veri tabanından retrospektif olarak incelendi. Prenatal ve neonatal özellikler, neonatal morbiditeler, maternal komorbiditeler ve tiroid fonksiyon test sonuçları değerlendirildi. Bulgular: Çalışma grubundaki prematüre bebeklerin 84’ü (%33,6) <28 haftalık, 166’sı (%66,4) ≥28–32 haftalık idi. Ortalama doğum ağırlığı 1177,62±451,01 gram olarak saptandı. Postnatal 5–7. günler arasında bakılan ilk TFT’de (sT4 ve TSH) 59 bebekte tiroid fonksiyon bozukluğu saptandı (32 hipotiroidi, 19 hipotiroksinemi, 8 hipertirotiropinemi). İlk TFT sonucu normal olan 191 prematüre bebeğin tekrarlanan testlerinde, tiroid fonksiyon bozukluğu gelişen 26 bebekte hiperglisemi ve intraventriküler kanama (İVK) sıklığı, TFT’si normal seyreden gruba kıyasla anlamlı olarak daha yüksek bulundu (sırasıyla p=0,001 ve p=0,008). İlk TFT’de tiroid fonksiyon bozukluğu saptanan 59 bebekte ise, YYBÜ izlemi sırasında erken sepsis, konjenital anomali, patent duktus arteriozus (PDA), nekrotizan enterokolit (NEK), intraventriküler kanama (İVK) tanıları ve cerrahi girişim gereksinimi, tiroid fonksiyon testleri normal olan prematüre bebeklere (n=165) göre istatistiksel olarak anlamlı derecede daha yüksek bulundu. Sonuç: Prematüre bebeklerde tiroid hormon düzeylerinin dikkatli ve tekrarlayan ölçümlerle izlenmesi, tiroid fonksiyon bozukluklarının zamanında tanınması ve uygun tedavinin başlatılması açısından büyük önem taşımaktadır.

Anahtar Kelimeler

• Konjenital hipotiroidi
• hipotiroksinemi
• tiroid fonksiyon bozukluğu
• prematüre doğum

Evaluation of Thyroid Function Disorders in Preterm Infants Born Before 32 Weeks

Öz

Thyroid hormones are essential for normal brain development. Premature infants have a high incidence of thyroid dysfunction due to the underdeveloped thyroid gland, immaturity of the thyroid axis, maternal thyroid disorders, medications used, and morbidities associated with prematurity. This study aims to evaluate the results of repeated thyroid function tests (TFT) during the monitoring of premature infants with a gestational age below 32 weeks in the Neonatal Intensive Care Unit (NICU) and to assess potential factors influencing these results. The study group consisted of 250 premature infants born at the NICU of Eskişehir Osmangazi University Faculty of Medicine Hospital between 2016 and 2021, with a gestational age of less than 32 weeks. The records of premature infants were examined from the hospital database, and prenatal, neonatal characteristics, neonatal morbidities, maternal comorbidities, and TFT results were evaluated. Among the premature infants in the study group, 84 (33.6%) were <28 weeks, and 166 (66.4%) were ≥28-32 weeks. The mean birth weight was determined to be 1177.62±451.01 grams. When the first TFT (sT4 and TSH) conducted between postnatal days 5-7 were examined, thyroid dysfunction was observed in 59 infants (32 hypothyroidism, 19 hypothyroxinemia, 8 hyperthyrotropinemia). Among the 191 premature infants with normal initial thyroid function tests, upon repeat testing, those with thyroid dysfunction (26 infants) were found to have a higher incidence of hyperglycemia and intraventricular hemorrhage (IVH) compared to the group with normal TFT results (p=0.001 and p=0.008, respectively). Among the 59 patients with thyroid dysfunction identified by the initial TFT results, it was observed that they statistically significantly received early sepsis, congenital anomalies, PDA, NEC, and IVH diagnoses, as well as underwent surgical operations, compared to premature infants with normal thyroid function tests (n=165) during their NICU monitoring. Vigilant monitoring of thyroid hormone levels in premature infants is crucial for timely diagnosis and initiation of treatment.

Anahtar Kelimeler

• Congenital hypothyroidism
• hypothyroxinemia
• thyroid dysfunction
• premature birth

Kaynakça

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