ESPE Abstracts

Background: Fibroblast growth factor 21 (FGF21) is one of the FGF superfamily, which regulates energy expenditure, glucose metabolism and lipid metabolism. FGF21 elevates of glucose uptake in peripheral tissues, and regulates body temperature in brown adipose tissue.

Objective and hypotheses: This study is to reveal which endocrine diseases in children has elevation of FGF21.

Method: We collected blood from 253 endocrine diseases in children, under 20-year-old, from April to December 2012 at Kurume University Hospital. Diseases were following: idiopathic short stature (90), GHD (20), short stature children born SGA (13), pan-hypopituitarism (5), Graves’ disease (7), Hashimoto disease (4), transient hyper-TSH (22), congenital hypothyroidism (CH; 50), T1DM (22), T2DM (3), 21OHD (4), central precocious puberty (9), hypochondroplasia (2), achondroplasia (2), and healthy control (59). FGF21 was measured by ELISA (BioVendor, Czech). Kruskal-Wallis test was used for statistical analysis.

Results: Only CH had significantly elevated FGF21 compared to control. Elevation of thyroid hormone increases FGF21 via THβ receptor and/or PPARα. This result implicated that administration of levothyroxine may be overdosed in CH. This study replicated previous literatures, in that T1DM had decreased FGF21, T2DM had increased FGF21, and growth was not related to FGF21.

Conclusion: CH had elevated FGF21, indicating that levothyroxine may be overdosed in CH. FGF21 may be a new biomarker for optimal levothyroxine dose in CH.