ASSESSMENT OF THYROID FUNCTION AND ULTRASONOGRAPHIC FINDINGS IN PATIENTS WITH MUCOPOLYSACCHARIDOSIS

Abstract

Objective: The thyroid gland, with its high vascularity and low proliferation index of thyrocytes, is highly susceptible to storage diseases, however it has not been evaluated adequately in patients with in mucopolysaccharidosis (MPS). Therefore, the aim of this study is to assess the function, morphology, B- mode, and Doppler ultrasonography features of the thyroid gland in pediatric and adolescent patients with MPS and to evaluate whether the thyroid gland is involved in this disease. Material and Methods: Thyroid hormone functions were measured in all patients, and B-mode ultrasound and color Doppler imaging were performed. Results: Eight boys and 17 girls with MPS were included in the study. Eight patients were diagnosed with MPS I, 2 with MPS II, 3 with MPS III, 3 with MPS IVA, and 9 with MPS VI. Nineteen patients were receiving enzyme replacement therapy, while three patients diagnosed with MPS III remained untreated due to the unavailability of treatment options. Thyroid hormone levels were within normal limits for all patients. B-Mode ultrasound imaging revealed slightly heterogeneous echo texture in only 2 (8%) patients, both with MPS VI. Except for one patient with MPS VI, all color Doppler assessments were within normal limits. Conclusion: The results of our study demonstrate that both thyroid function tests and thyroid gland morphology are normal in MPS through childhood and adolescence. Therefore, we believe that thyroid gland dysfunction does not play a crucial role in the development of symptoms such as growth retardation, dry skin, coarse facial features, and intellectual disability, which could potentially be attributed to thyroid dysfunction. Instead, we think that these findings are more likely attributed to the primary disease involvement process

Keywords

• Glycosaminoglycan
• mucopolysaccharidosis
• thyroid
• thyroid functions
• thyroid ultrasonography

Supporting Institution

This study received no funding.

Ethical Statement

Informed written consent was acquired from the legal guardians of all participants. The study adhered to the ethical principles outlined in the Helsinki Declaration and received approval from the local Ethics Committee on March 16, 2023, with the approval number 2023/06-04.

Thanks

The authors acknowledge and thank Zekiye Küpçü for her assistance with the endocrinologic evaluation.

Mukopolisakkaridozlu Hastalarda Tiroid Bezinin Fonksiyonel ve Ultrasonografik Değerlendirmesi

Abstract

Amaç: Tiroid bezi yüksek vaskülarite ve düşük tirosit çoğalma indeksine sahip olduğundan depo hastalıklarına karşı oldukça duyarlıdır ancak mukopolisakkaridoz (MPS) hastalarında yeterince değerlendirilmemiştir. Bu nedenle çalışmamızın amacı MPS'li pediatrik ve adölesan hastalarda tiroid bezinin fonksiyon, morfoloji, B-mod ve Doppler ultrasonografi özelliklerini ve tiroid bezinin bu hastalıktaki etkilenimini değerlendirmektir. Gereç ve Yöntemler: Tüm hastaların tiroid hormon fonksiyonları ve antikorları değerlendirildi ve B-mod ultrason ve renkli Doppler ultrasonografisi ile görüntüleme yapıldı. Bulgular: Çalışmaya MPS'li 8 erkek ve 17 kız dahil edildi. Sekiz hastaya MPS I, 2'sine MPS II, 3'üne MPS III, 3'üne MPS IVA ve 9'una MPS VI tanısı ile takipliydi. On dokuz hasta enzim replasman tedavisi alırken, MPS III tanısı alan üç hasta tedavi seçeneklerinin mevcut olmaması nedeniyle tedavi edilmedi. Tüm hastaların tiroid hormon düzeyleri normal sınırlardaydı. B-Mode ultrason görüntülemede, her ikisi de MPS VI tanılı olan yalnızca 2 (%8) hastada hafif heterojen eko dokusunu saptandı. MPS VI tanısı ile izlenen bir hasta dışında tüm renkli Doppler değerlendirmeleri normal sınırlardaydı. Sonuç: Çalışmamızın sonuçları MPS'de çocukluk ve ergenlik döneminde hem tiroid bezi fonksiyon testlerinin hem de tiroid bezi morfolojisinin normal olduğunu göstermektedir. Bu nedenle büyüme geriliği, cilt kuruluğu, kaba yüz hatları, zihinsel yetersizlik gibi potansiyel olarak tiroid fonksiyon bozukluğunda görülebilecek semptomların gelişiminde tiroid bezi fonksiyon bozukluğunun önemli bir rol oynamadığına inanıyoruz. Bunun yerine, bu bulguların daha çok birincil hastalık tutulum sürecine bağlı olduğunu düşünmekteyiz.

Keywords

• Glikozaminoglikan
• mukopolisakkaridoz
• tiroid
• tiroid fonksiyonları
• tiroid ultrasonografisi

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