Aim
X-linked hypophosphatemia (XLH), the most common form of hereditary rickets,
Conclusion
Our findings revealed the PHEX genotypic variants and FGF23 levels in Taiwanese patients with XLH. These results are crucial given the recent approval of burosumab, a monoclonal FGF23 antibody, for XLH therapy. This study provides key insights into the clinical management of XLH in Taiwan.
Methods
We retrospectively reviewed the records of 102 patients clinically suspected of having hypophosphatemic rickets from 2006 to 2022. Serum intact Fibroblast growth factor-23 (iFGF23) levels were measured on clinic visit days. PHEX mutations were identified using Sanger sequencing, and negative cases were analyzed using whole-exome sequencing.
Results
The majority (92.1%) of patients exhibited elevated FGF23 compared with normal individuals. Among 102 patients, 44 distinct PHEX mutations were identified. Several mutations recurred in multiple unrelated Taiwanese families. We discovered a high frequency of novel PHEX mutations and identified variants associated with extreme FGF23 elevation and tumorigenesis.