Keywords
Thyroid-stimulating hormone
Thyroxine
Children
Low Probability
Primary hypothyroidism
Antithyroid antibodies
Goiter
Treatment
How to Cite
Abstract
Background: Subclinical hypothyroidism (SH) is defined as a serum thyroid-stimulating hormone (TSH) concentration above the reference range with normal free thyroxine (fT4) levels. It is a common condition in children, usually asymptomatic and with a low probability of progressing to primary hypothyroidism.
Purpose: To evaluate the natural course of SH in children over a 2-year follow-up period.
Methods: A total of 42 children (18 boys and 24 girls) were followed for 2 years. TSH, free T4, and antithyroid antibodies were measured every 6 months. Growth velocity and the presence of clinical goiter were assessed according to the 2007 WHO classification.
Results: The mean age was 9.7 ± 2.8 years. Initial TSH was 6.3 ± 1.4 mUI/ml, with fT4 at 1.1 ± 0.3. At 6 months, 14 children (six boys and eight girls) showed normal TSH and fT4 levels, while 28 continued with elevated TSH (7.2 ± 1.2) and normal fT4 (1.0 ± 0.2); growth velocity remained normal and no associated symptoms were observed. At 12 months, 20 children presented normal TSH and fT4 levels; eight continued with elevated TSH and normal fT4. At 18 months, two girls showed elevated TSH with positive antithyroid antibodies and began treatment with levothyroxine. The remaining six showed normal TSH and fT4. The incidence of progression to hypothyroidism was 4.7%.
Conclusions: SH is a self-limited condition with a low rate of progression. Treatment in children should be considered only when TSH > 10 mUI/L, clinical goiter is present, or antithyroid antibodies are positive.
References
Murillo-Vallés M, Martinez S, Aguilar-Riera C, Garcia-Martin MA, Bel-Comós J, Granada Ybern ML. Subclinical hypothyroidism in childhood, treatment or only follow-up? BMC Pediatr. 2020;20(1):282. https://doi.org/10.1186/s12887-020-02177-8
Szeliga K, Antosz A, Skrzynska K, Kalina-Faska B, Gawlik A. Subclinical hypothyroidism in children and adolescents as mild dysfunction of the thyroid gland: a single-center study. Pediatr Endocrinol Diabetes Metab. 2023;29(2):97-103. https://doi.org/10.5114/pedm.2023.124266
Crisafulli G, Aversa T, Zirilli G, Pajno GB, Corica D, De Luca F, et al. Subclinical hypothyroidism in children: when a replacement hormonal treatment might be advisable. Front Endocrinol. 2019;10:109. https://doi.org/10.3389/fendo.2019.00109
Metwalley KA, Farghaly HS. Subclinical hypothyroidism in children: updates for pediatricians. Ann Pediatr Endocrinol Metab. 2021;26(2):80-5. https://doi.org/10.6065/apem.2040242.121
Wu T, Flowers JW, Tudiver F, Wilson JL, Punyasavatsut N. Subclinical thyroid disorders and cognitive performance among adolescents in the United States. BMC Pediatr. 2006;6:12. https://doi.org/10.1186/1471-2431-6-12
Lazar L, Frumkin RBD, Battat E, Lebenthal Y, Phillip M, Meyerovitch J. Natural history of thyroid function tests over 5 years in a large pediatric cohort. J Clin Endocrinol Metab. 2009;94:1678-82. https://doi.org/10.1210/jc.2008-2615
Salerno M, Capalbo D, Cerbone M, De Luca F. Subclinical hypothyroidism in childhood-current knowledge and open issues. Nat Rev Endocrinol. 2016;12(12):734-46. https://doi.org/10.1038/nrendo.2016.100
Karmisholt J, Andersen S, Laurberg P. Variation in thyroid function in subclinical hypothyroidism: importance of clinical follow?up and therapy. Eur J Endocrinol. 2011;164(3):317-23. https://doi.org/10.1530/eje-10-1021
Monzani A, Prodam F, Bellone S, Bona G. Subclinical hypothyrodism. En: Bona G, De Luca F, Monzani A, editores. Thyroid diseases in childhood: recent advances from basic science to clinical practice. Basel. Springer International Publishing; 2015. p. 195-202.
Moore DC. Natural course of ‘subclinical’ hypothyroidism in childhood and adolescence. Arch Pediatr Adolesc Med. 1996;150(3):293-7. https://doi.org/10.1001/archpedi.1996.02170280063012
Monzani A, Prodam F, Rapa A, Moia S, Agarla V, Bellone S, et al. Endocrine disorders in childhood and adolescence. Natural history of subclinical hypothyroidism in children and adolescents and potential effects of replace ment therapy: a review. Eur J Endocrinol. 2012;168(1):R1-11. https://doi.org/10.1530/eje-12-0656
Lazarus J, Brown RS, Daumerie C, Hubalewska-Dydejczyk A, Negro R, Vaidya B. 2014 European thyroid association guidelines for the management of subclinical hypothyroidism in pregnancy and in children. Eur Thyroid J. 2014;3(2):76-94. https://doi.org/10.1159/000362597
Wasniewska M, Salerno M, Cassio A, Corrias A, Aversa T, Zirilli G, et al. Prospective evaluation of the natural course of idiopathic subclinical hypothyroidism in childhood and adolescence. Eur J Endocrinol. 2009;160(3):417-21. https://doi.org/10.1530/eje-08-0625
Rapa A, Monzani A, Moia S, Vivenza D, Bellone S, Petri A, et al. Subclinical hypothyroidism in children and adolescents: a wide range of clinical, biochemical, and genetic factors involved. J Clin Endocrinol Metab. 2009;94(7):2414-20. https://doi.org/10.1210/jc.2009-0375
Radetti G, Maselli M, Buzi F, Corrias A, Mussa A, Cambiaso P, et al. The natural history of the normal/mild elevated TSH serum levels in children and adolescents with Hashimoto’s thyroiditis and isolated hyperthyrotropinaemia: a 3-year follow-up. Clin Endocrinol. 2012;76(3):394-8. https://doi.org/10.1111/j.1365-2265.2011.04251.x
Such K, Gawlik A, Dejner A, Wasniewska M, Zachurzok A, Antosz A, et al. Evaluation of subclinical hypothyroidism in children and adolescents: a single-center study. Int J Endocrinol. 2016:1671820. https://doi.org/10.1155/2016/1671820
Ergin Z, Sava?-Erdeve S, Kurnaz E, Çetinkaya S, Aycan Z. Follow-up in children with non-obese and non-autoimmune subclinical hypothyroidism. J Pediatr Endocrinol Metab. 2018;31(10):1133-8. https://doi.org/10.1515/jpem-2018-0095
Gammons S, Presley BK, White PC. Referrals for elevated thyroid stimulating hormone to pediatric endocrinologists. J Endocr Soc. 2019;3(11): 2032-40. https://doi.org/10.1210/js.2019-00244
Wasniewska M, Aversa T, Salerno M, Corrias A, Messina MF, Mussa A, et al. Five-year prospective evaluation of thyroid function in girls with subclinical mild hypothyroidism of different etiology. Eur J Endocrinol. 2015;173(6):801-8. https://doi.org/10.1530/eje-15-0484
Wasniewska M, Corrias A, Aversa T, Valenzise M, Mussa A, De Martino L, et al. Comparative evaluation of therapy with l-thyroxine versus no treatment in children with idiopathic and mild subclinical hypothyroidism. Horm Res Paediatr. 2012;77(6):376-81. https://doi.org/10.1159/000339156
Lipp RW, Scherer T, Krebs M. Is thyroxine therapy indicated in any case of subclinical hypothyroidism? Austrian J Clin Endocrinol Metab. 2013;6(2):12-6.
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