Thyroid Dysfunction in Down syndrome Patients; Clinical and Chromosomal Correlation

Öz

Objective: Autoimmune diseases are known to occur in people with Down syndrome, especially the hypothyroidism. The main objectives of the present study were to estimate the frequency of abnormal thyroid function in Down syndrome patients and to assess their relation to the age, craniofacial features and the type of chromosomal abnormalities in Duhok province, Iraq.

Materials and Methods: The study included fifty eight patients with Down syndrome; all of them were examined for the presence of the main craniofacial features. Blood samples were collected from them to perform the thyroid function test and the karyotyping for chromosomal analysis. 

Results: Out of 58 patients with Down syndrome, 25(43.11%) had subclinical hypothyroidism. There was no statistical significance between age group and percentage of subclinical hypothyroidism. The most frequent craniofacial feature was the epicanthal folds with a relatively high percentage of subclinical hypothyroidism, but this result was statistically insignificant. Trisomy was the commonest chromosomal abnormality seen in 56(96.56%) patients and only 2(3.45%) were mosaic. No translocation was detected. All the cases of hypothyroidism were numerical chromosomal abnormality of Trisomy 21.

Conclusions: The subclinical hypothyroidism was the commonest thyroid dysfunction seen in Down syndrome patients with no significant differences in all age groups.

Anahtar Kelimeler

• Chromosomal abnormalities,Down syndrome,thyroid function

Down Sendromlu Hastalarda Tiroid Disfonksiyonu; Klinik ve Kromozom Korelasyonu

Öz

Amaç: Otoimmün hastalıkların Down sendromlu kişilerde, özellikle hipotiroidizmde meydana geldiği bilinmektedir. Bu çalışmanın temel amacı, Down sendromlu hastalarda anormal tiroid fonksiyonunun sıklığını tahmin etmek ve Irak, Duhok eyaletindeki yaş, kraniyofasiyal özellikler ve kromozomal anormalliklerin türü ile ilişkilerini değerlendirmektir.

Materyal ve Metot: Çalışmaya Down sendromlu 58 hasta dahil edilmiş; hepsi ana kraniyofasiyal özelliklerin varlığı açısından incelenmiştir. Tiroid fonksiyon testi ve kromozomal analiz için karyotipleme yapmak için olgulardan kan örnekleri alındı.

Bulgular: Down sendromlu 58 hastanın 25'inde (% 43.11) subklinik hipotiroidi vardı. Yaş grubu ile subklinik hipotiroidi yüzdesi arasında istatistiksel anlamlılık yoktu. En sık görülen kraniyofasiyal özellik, nispeten yüksek bir subklinik hipotiroidizm yüzdesine sahip epikantal kıvrımlar olmasına rağmen bu sonuç istatistiksel olarak anlamsızdı. Trizomi 56 (% 96.56) hastada en sık görülen kromozomal anormallik iken olgulardan sadece 2 (% 3.45) mozaikti. Translokasyon tespit edilmedi. Tüm hipotiroidizm vakaları Trizomi 21'in sayısal kromozomal anomalisidir.

Sonuç: Subklinik hipotiroidi, Down sendromlu hastalarda görülen ve tüm yaş gruplarında anlamlı farklılık göstermeyen en yaygın tiroid fonksiyon bozukluğuydu.

Anahtar Kelimeler

• Down sendromu,kromozomal anormallikler,tiroid fonksiyonu

Kaynakça

1. 1. Salih D, Bakir N, Adil E, Al-Allawi N. Clinical and Cytogenetic Profile in Patients with Down Syndrome in Duhok Province, Iraq. Medical Journal of Babylon. 2017;14(2):389-401.
2. 2. Keppler-Noreuil K, Welch J, Major H, Qiau Q, Jordan D, Patil S. Atypical Down syndrome phenotype with severe developmental delay, hypertonia, and seizures in a child with translocation trisomy 21. Dev Med Child Neurol. 2002;44(1):64-67.
3. 3. Purdy B, Singh N, Brown W, Vangala S, Devaskar U. Revisiting early hypothyroidism screening in infants with Down syndrome. J Perinatol. 2014;34(12):936–940.
4. 4. Davidson M. Primary care for children and adolescents with Down's syndrome. Pediatric Clinics of North America. 2008;55:1099-1111.
5. 5. Kawther T, El-Shafie K. Clinical presentation of Hypothyroidism. J Family Community Med. 2003;10(1):55-58.
6. 6. Marilyn J. Clinical report-health supervision for children with Down syndrome. Pediatrics. 2011;128(2):383-406.
7. 7. Cunniff C, Frias J, Kaye C, Moeschler J, Panny S, Trotter T. American Academy of Pediatrics, Committee on Genetics Health supervision for children with Down syndrome. Pediatrics. 2001;107:442-450.
8. 8. Henry E, Walker D, Wiedmeier S. Hematological abnormalities during the first week of life among neonates with Down syndrome: data from a multihospital healthcare system. American Journal of Medical Genetic. 2007;143:42-50.

9. 9. Tonacchera M, Perri A, De Marco G. TSH receptor and GS (alpha) genetic analysis in children with Down's syndrome and subclinical hypothyroidism. J Endocrinol Invest. 2003;26:997-1000.
10. 10. Acikbas I, Tomatir A, Akdag B, Koksal A. Sixteen years live-birth prevalence of children with Down syndrome in Denizli, Turkey. Genetics and Molecular Research. 2002;11(4):4640-4645.
11. 11. Zahed Y, Vahedi A, Zamani M, Alizadeh-Navaei R, Zahed E. Prevalence of Birth Defects in Iran: A Systematic Review and Meta-Analysis. Arch Iran Med. 2017;20(6):376-385.
12. 12. Fergeson M, Mulvihill J, Schaefer G, DeHaai K, Piat J, Combs K. Low adherence to national guidelines for thyroid screening in Down syndrome. Genetics in Medicine. 2009;11(7):548-551
13. 13. Bull M. Health supervision for children with Down syndrome. Pediatrics. 2011;128(2):393-406.
14. 14. Oliveira A, Longui C, Calliari E, Ferone A, Kawaguti F, Monte O. Evaluation of the hypothalamic-pituitary-thyroid axis in children with Down syndrome. J Pediatr. 2002;78(4):295-300.
15. 15. Cebeci A, Güven A, Yıldız M. Profile of Hypothyroidism in Down’s syndrome. J Clin Res Pediatr Endocrinol. 2013;5(2):116-120.
16. 16. Gibson P, Newton R, Selby K, Price D, Leyland K, Addison G. Longitudinal study of thyroid function in Down’s syndrome in the first two decades. Arch Dis Child. 2005;90:574-578.
17. 17. Predieri B, Garavelli L, Bonetti A, Vellani G, Predieri F,Cattelani C. Hypothyroidism in the Newborn Period. NCBR. 2013;20(5):449-454
18. 18. Al-Shawaf R, Al-Faleh W. Craniofacial characteristics in Saudi Down’s syndrome. King Saud University Journal of Dental Sciences. 2011;2:17-22.