Hyperparathyroidism in Patients With X-Linked Hypophosphatemia.

X-linked hypophosphatemia (XLH) is characterized by increased activity of circulating FGF23 resulting in renal phosphate wasting and abnormal bone mineralization. Hyperparathyroidism may develop in XLH patients; however, its prevalence, pathogenesis, and clinical presentation are not documented. This observational study (CNIL 171036 v 0) recruited XLH adult patients in a single tertiary referral center.