Etiology of congenital hypothyroidism in Isfahan: Does it different?

Authors

1 Department of Pediatrics; Isfahan Endocrine and Metabolism Research Center; Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Department of Pediatrics, Isfahan University of Medical Sciences, Isfahan, Iran

3 Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

4 Isfahan Health Center, Isfahan University of Medical Sciences, Isfahan, Iran

5 Department of Biostatistics and Epidemiology, Health School, Isfahan University of Medical Sciences, Isfahan, Iran

6 Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: Considering the higher prevalence of congenital hypothyroidism (CH) in Iran and the importance of determination of the etiology of CH for assessing appropriate treatment strategies, understanding the pathogenesis of CH and the implications of its inheritance and prognosis, the aim of this study was to determine the etiology of CH 7 years after initiation of the program in Isfahan province.
Materials and Methods: In this cross-sectional study, children with a primary diagnosis of CH studied. They clinically examined and their medical files were reviewed by a Pediatric Endocrinologist. Considering screening and follow-up lab data and radiologic findings the etiology of CH was determined. Screening properties of different etiologies of CH was compared.
Results: In this study, 437 patients with permanent CH (PCH) were studied. Etiology of PCH in 316 (72.3%) and 121 (27.7%) of cases was thyroid dyshormonogenesis and thyroid dysgenesis, respectively. Prevalence of agenesis, ectopia, hypoplasia and hemiagenesis in thyroid dysgenetic patients was 13.3%, 6.4%, 4.3% and 3.7% respectively. Mean of thyroid stimulating hormone in screening, recall and after discontinuing treatment at 3 years of age was significantly lower in dyshormonogenetic CH patients than dysgenetic ones(P < 0.01).
Conclusion: Seven years of our experiences in CH screening program indicated that the etiology of CH in Isfahan, with a higher rate of CH, with a predominance of thyroid dyshormonogenesis is different from most of the studies world-wide and similar to other reports from Iran. The findings of the current study provide us baseline information for determination of CH pathogenesis in this region.

Keywords

1. Rastogi MV, LaFranchi SH. Congenital hypothyroidism. Orphanet J Rare Dis 2010;5:17.  Back to cited text no. 1
[PUBMED]    
2. Büyükgebiz A. Newborn screening for congenital hypothyroidism. J Pediatr Endocrinol Metab 2006;19:1291-8.  Back to cited text no. 2
    
3. American Academy of Pediatrics, Rose SR, Section on Endocrinology and Committee on Genetics, American Thyroid Association, Brown RS, Public Health Committee, Lawson Wilkins Pediatric Endocrine Society, Foley T, et al. Update of newborn screening and therapy for congenital hypothyroidism. Pediatrics 2006;117:2290-303.  Back to cited text no. 3
    
4. Brown RS, Demmer LA. The etiology of thyroid dysgenesis-still an enigma after all these years. J Clin Endocrinol Metab 2002;87:4069-71.  Back to cited text no. 4
[PUBMED]    
5. LaFranchi SH. Approach to the diagnosis and treatment of neonatal hypothyroidism. J Clin Endocrinol Metab 2011;96:2959-67.  Back to cited text no. 5
[PUBMED]    
6. Olney RS, Grosse SD, Vogt RF Jr. Prevalence of congenital hypothyroidism - Current trends and future directions: Workshop summary. Pediatrics 2010;125 Suppl 2:S31-6.  Back to cited text no. 6
[PUBMED]    
7. Mathai S, Cutfield WS, Gunn AJ, Webster D, Jefferies C, Robinson E, et al. A novel therapeutic paradigm to treat congenital hypothyroidism. Clin Endocrinol (Oxf) 2008;69:142-7.  Back to cited text no. 7
    
8. LaFranchi SH. Should the levothyroxine starting dose be tailored to disease severity in neonates with congenital hypothyroidism? Nat Clin Pract Endocrinol Metab 2008;4:658-9.  Back to cited text no. 8
[PUBMED]    
9. Karimzadeh Z, Amirhakimi GH. Incidence of congenital hypothyroidism in Fars province, Iran. Iran Med Sci 1992;17:78-80.  Back to cited text no. 9
    
10. Ordookhani A, Mirmiran P, Hedayati M, Hajipour R, Azizi F. Screening for congenital hypothyroidism in Tehran and Damavand: an interim report on descriptive and etiologic findings,1998-2001. Iran J Endocrinol Metab 2002;4:153-60.  Back to cited text no. 10
    
11. Hashemipour M, Amini M, Iranpour R, Sadri GH, Javaheri N, Haghighi S, et al. Prevalence of congenital hypothyroidism in Isfahan, Iran: Results of a survey on 20,000 neonates. Horm Res 2004;62:79-83.  Back to cited text no. 11
    
12. Ordookhani A, Mirmiran P, Pourafkari M, Neshandar-Asl E, Fotouhi F, Hedayati M, et al. Permanent and transient neonatal hypothyroidism in Tehran. Iran J Endocrinol Metab 2004;6:5-11.  Back to cited text no. 12
    
13. Karamizadeh Z, Dalili S, Sanei-Far H, Karamifard H, Mohammadi H, Amirhakimi G. Does congenital hypothyroidism have different etiologies in iran? Iran J Pediatr 2011;21:188-92.  Back to cited text no. 13
[PUBMED]    
14. Hashemipour M, Hovsepian S, Kelishadi R, Iranpour R, Hadian R, Haghighi S, et al. Permanent and transient congenital hypothyroidism in Isfahan-Iran. J Med Screen 2009;16:11-6.  Back to cited text no. 14
    
15. Adibi A, Haghighi M, Hosseini SR, Hashemipour M, Amini M, Hovsepian S. Thyroid abnormalities among first-degree relatives of children with congenital hypothyroidism: An ultrasound survey. Horm Res 2008;70:100-4.  Back to cited text no. 15
[PUBMED]    
16. Fisher DA. Disorders of the thyroid in the newborn and infants. In: Sperling MA, editor. Pediatric Endocrinology. 2 nd ed. Philadelphia: WB Saunders; 2008. p. 161-86.  Back to cited text no. 16
    
17. Brown RS. The thyroid gland. In: Brook CG, Hindmarsh PC, editors. Clinical Pediatric Endocrinology. 4 th ed. Ames, Lowa: Blackwell Science Ltd.; 2001. p. 288-320.  Back to cited text no. 17
    
18. al-Jurayyan NA, Shaheen FI, al-Nuaim AA, el-Desouki MI, Faiz A, al Herbish AS, et al. Congenital hypothyroidism: Increased incidence in Najran province, Saudi Arabia. J Trop Pediatr 1996;42:348-51.  Back to cited text no. 18
[PUBMED]    
19. Eugster EA, LeMay D, Zerin JM, Pescovitz OH. Definitive diagnosis in children with congenital hypothyroidism. J Pediatr 2004;144:643-7.  Back to cited text no. 19
[PUBMED]    
20. Hashemipour M, Amini M, Talaie M, Kelishadi R, Hovespian S, Iranpour R, et al. Parental consanguinity among parents of neonates with congenital hypothyroidism in Isfahan. East Mediterr Health J 2007;13:567-74.  Back to cited text no. 20
[PUBMED]    
21. Park SM, Chatterjee VK. Genetics of congenital hypothyroidism. J Med Genet 2005;42:379-89.  Back to cited text no. 21
[PUBMED]    
22. Silva LO, Dias VM, Silva IN, Chagas AJ. Congenital transient hypothyroidism: Characteristics of children identified at Newborn Screening Program of the State of Minas Gerais, Brazil. Arq Bras Endocrinol Metabol 2005;49:521-8.  Back to cited text no. 22
    
23. Hashemipour M, Hasani N, Amini M, Heidari K, Sajadi A, Dastanpour M, et al. Thyroid function abnormalities among first-degree relatives of Iranian congenital hypothyroidism neonates. Pediatr Int 2010;52:467-71.  Back to cited text no. 23
    
24. Hanukoglu A, Perlman K, Shamis I, Brnjac L, Rovet J, Daneman D. Relationship of etiology to treatment in congenital hypothyroidism. J Clin Endocrinol Metab 2001;86:186-91.  Back to cited text no. 24
    
25. Medda E, Olivieri A, Stazi MA, Grandolfo ME, Fazzini C, Baserga M, et al. Risk factors for congenital hypothyroidism: Results of a population case-control study (1997-2003). Eur J Endocrinol 2005;153:765-73.  Back to cited text no. 25
    
26. Oakley GA, Muir T, Ray M, Girdwood RW, Kennedy R, Donaldson MD. Increased incidence of congenital malformations in children with transient thyroid-stimulating hormone elevation on neonatal screening. J Pediatr 1998;132:726-30.  Back to cited text no. 26
[PUBMED]    
27. Hinton CF, Harris KB, Borgfeld L, Drummond-Borg M, Eaton R, Lorey F, et al. Trends in incidence rates of congenital hypothyroidism related to select demographic factors: Data from the United States, California, Massachusetts, New York, and Texas. Pediatrics 2010;125 Suppl 2:S37-47.  Back to cited text no. 27