Increased Sex Hormone-Binding Globulin Levels in Children and Adolescents with Thyrotoxicosis

Abstract

Background: Thyrotoxicosis is a rare condition in pediatric patients, and optimal treatment can be difficult to achieve in some children. To our knowledge, no studies have evaluated sex hormone-binding globulin (SHBG) levels in hyperthyroid children and adolescents in relation to age- and gender-related normative data. Methods: SHBG serum levels were determined before and after 4 months of antithyroid therapy (ATT) in 10 children and adolescents with Graves' disease. A total of 903 healthy children and adolescents served as controls. Results: Serum SHBG levels were elevated (>2 SD) at diagnosis in all hyperthyroid children but normalized rapidly following ATT. At diagnosis, median SHBG was +2.51 SD (interquartile range 2.20-3.27) compared to healthy children without thyroid illness, and it declined significantly during ATT (-0.16 SD, -0.66 to 1.64; p < 0.05). Conclusion: This is the first study to demonstrate that serum SHBG levels are markedly increased in children with Graves' disease, and we suggest that SHBG may be an additional marker of thyroid hormone action in children, as has been shown in adults.