X-linked rickets and tumor-acquired osteomalacia:PHEX and the missing link

Abstract

Dietary rickets has been recognized as a major cause of skeletal abnormalities in the industrialized world for more than 350 years. In recent times, familial and tumor forms of rickets were found to be resistant to vitamin D3 supplementation and light. The main nondietary types of rickets and osteomalacia include: a) X-linked vitamin D-resistant, hypophosphatemic rickets; b) hereditary hypercalciuria with hypophosphatemic rickets; c) Dent's disease including certain types of renal Fanconi syndrome; d) renal 1α-hydroxylase deficiency; e) defects in the 1,25-dihydroxy vitamin D3 receptor (end-organ resistance); f) autosomal dominant forms of rickets; and g) oncogenic hypophosphatemic osteomalacia. This review will describe the recent advances in our knowledge of the molecular defects in hypophosphatemic rickets and tumor-acquired osteomalacia.