Therapeutic Response to Burosumab in a Child with X-Linked Hypophosphatemia: A Case Report

Luisa Muskus Diaz, Ana Maria Seplveda Gomez, Carlos Aguirre Acevedo, Jorge Ordoez Hernandez

Abstract: X-linked hypophosphatemic rickets (XLH) is a rare disorder caused by mutations in the PHEX gene, resulting in the overexpression of fibroblast growth factor 23 (FGF23), a hormone that decreases renal phosphate reabsorption and active vitamin D synthesis. This report presents the case of a 3-year-old girl clinically diagnosed with XLH, presenting with bone deformities such as genu valgum, delayed motor development, and dysmorphic features. The diagnosis was confirmed through genetic testing identifying a pathogenic variant in the PHEX gene. The patient was treated with burosumab, a monoclonal antibody that inhibits FGF23. Following treatment, significant improvements were observed, including an increase in serum phosphate levels and decreases in alkaline phosphatase and parathyroid hormone (PTH) levels, demonstrating burosumab?s role in improving clinical outcomes.

Keywords: X-linked hypophosphatemic rickets, XLH, Burosumab, FGF23, pediatric, case report

How to Cite?: Luisa Muskus Diaz, Ana Maria Seplveda Gomez, Carlos Aguirre Acevedo, Jorge Ordoez Hernandez, "Therapeutic Response to Burosumab in a Child with X-Linked Hypophosphatemia: A Case Report", Volume 14 Issue 5, May 2025, International Journal of Science and Research (IJSR), Pages: 755-758, https://www.ijsr.net/getabstract.php?paperid=SR25511040515, DOI: https://dx.doi.org/10.21275/SR25511040515