Hypophosphatemic rickets and short stature.

This article focuses on a clinical case of autosomal dominant hypophosphatemic rickets (ADHR), a rare genetic disorder caused by pathogenic variants in the fibroblast growth factor 23 (FGF23) gene leading to renal phosphate wasting and hypophosphatemia. An 18-month-old male presenting with short stature, developmental delay, metaphyseal abnormalities, and sagittal craniosynostosis was diagnosed with ADHR after biochemical and genetic testing revealed elevated FGF23 activity and a specific FGF23 mutation. The case highlights the critical role of iron deficiency in exacerbating ADHR symptoms, as iron supplementation normalized FGF23 levels and phosphate metabolism, allowing discontinuation of phosphate and calcitriol therapy and resulting in clinical improvement. The report underscores the importance of including hypophosphatemia in the differential diagnosis of short stature and rickets, the variable penetrance of ADHR within families, and the potential for iron repletion to manage this condition effectively.