Pediatric and Adolescent Endocrinology, Division of Pediatrics, Department of Obstetrics, Gynecology and Pediatrics, University Hospital, Pisa, Italy.
Chemistry and Endocrinology Laboratory, Department of Laboratory Medicine, University Hospital, Pisa, Italy.
J Endocrinol Invest. 2024 Apr;47(4):873-882. doi: 10.1007/s40618-023-02202-4. Epub 2023 Nov 22.
FGF23 measurement may have a diagnostic role to investigate patients with phosphate disorders. However, normal values for infants, children, and adolescents have not been defined.
In a total of 282 (males 145, females 137) healthy infants (n = 30), prepubertal (n = 147), pubertal (n = 59), and postpubertal (n = 46), and in twenty patients with X-linked hypophosphatemic rickets (XLH, age 10.2 ± 5.6 years) serum phosphate (automated analyzer), and plasma intact FGF23 (immunochemiluminescent sandwich assay, DiaSorin) concentrations were measured.
Intact FGF23 concentrations were higher in healthy infants than in prepubertal (P < 0.01) and postpubertal subjects (P < 0.05); pubertal subjects showed higher values (P < 0.05) than postpubertal subjects. Serum phosphate concentrations were higher (P < 0.001) in healthy infants than in prepubertal, pubertal, and postpubertal subjects. Pubertal subjects had higher (P < 0.001) serum phosphate concentrations than postpubertal subjects. Intact FGF23 and serum phosphate concentrations did not differ (P = NS) by sex, age of menarche, and time after menarche. In healthy subjects, there was no correlation between intact FGF23 and serum phosphate concentrations. Intact FGF23 concentrations were higher (P < 0.0001) in patients with XLH than in healthy subjects according to chronological age and pubertal development. In all patients, intact FGF23 concentrations were above 40 pg/mL; intact FGF23 concentrations were inversely correlated with serum phosphate concentrations (r = -0.65; P < 0.01).
In healthy subjects, chronological age and puberty were main determinants of intact FGF23 concentrations. Intact FGF23 concentrations may be a useful marker for the early diagnosis of XLH in pediatric patients.
FGF23 检测可能对诊断磷酸盐代谢紊乱患者具有一定作用。然而，目前尚未明确婴幼儿及青少年的正常参考值范围。
本研究共纳入 282 名健康婴幼儿（男 145 例，女 137 例，年龄 30 天至 3 岁）、青春期前（147 例，年龄 4 至 10 岁）、青春期（59 例，年龄 10 至 18 岁）和青春期后（46 例，年龄 18 至 21 岁），并纳入 20 例 X 连锁低磷血症佝偻病（XLH）患者（年龄 10.2 ± 5.6 岁），采用全自动生化分析仪检测血清磷酸盐浓度，应用化学发光免疫分析检测血循环完整 FGF23 浓度。
与青春期前（P<0.01）和青春期后（P<0.05）健康婴幼儿相比，健康婴儿的血循环完整 FGF23 浓度更高；青春期组的血循环完整 FGF23 浓度也高于青春期后组（P<0.05）。与青春期前、青春期和青春期后健康婴幼儿相比，健康婴儿的血清磷酸盐浓度更高（P<0.001）。与青春期后健康婴幼儿相比，青春期组的血清磷酸盐浓度更高（P<0.001）。健康婴幼儿的血循环完整 FGF23 浓度与血清磷酸盐浓度之间无相关性（P=NS）。健康婴幼儿的血循环完整 FGF23 浓度与性别、初潮年龄和初潮后时间无关。根据实际年龄和青春期发育情况，XLH 患者的血循环完整 FGF23 浓度明显高于健康对照组（P<0.0001）。所有患者的血循环完整 FGF23 浓度均>40pg/ml；血循环完整 FGF23 浓度与血清磷酸盐浓度呈负相关（r=-0.65，P<0.01）。
在健康婴幼儿中，实际年龄和青春期是血循环完整 FGF23 浓度的主要决定因素。血循环完整 FGF23 浓度可能是儿科 XLH 患者早期诊断的有用标志物。
