New clinical research has identified a significant delay in skeletal maturation among children with X-linked hypophosphatemia (XLH), with male patients experiencing notably more pronounced delays than females. The study, published in Journal of The Endocrine Society , highlights a significant gap between chronological age and bone age (BA).
These findings provide clinicians with more precise benchmarks for predicting adult height and managing the complex growth trajectories of pediatric XLH cases. At its core, XLH is a rare genetic disorder typically driven by mutations in the PHEX gene located on the X chromosome.
This genetic anomaly leads to an overproduction of fibroblast growth factor 23 (FGF23), a hormone that regulates blood phosphate levels. Elevated FGF23 inhibits the kidneys’ ability to reabsorb phosphate into the bloodstream and simultaneously reduces the production of active vitamin D.
The resulting “phosphate wasting” creates a state of chronic hypophosphatemia, which starves developing bone of mineral. Thus, children with XLH often develop rickets and osteomalacia, characterized by impaired mineralization of the growth plate.
Endocrine News published a clinical update in Research Highlights on 07 Apr 2026.
The item focuses on Beyond the Curve: How XLH Impacts Skeletal Maturation and Predicted Height.
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