Rickets is defined by a deficiency in vitamin D resulting in growth retardation and bone deformity.
The differentiation of rickets starts with vitamin D (colecalciferol) substitution when hypercalcemia is excluded. In cases where in spite of this therapy a low concentration of 1,25-dihydroxy vitamin D3 can be found and a kidney disease can be excluded a defect in 1-alpha hydroxylation can be suspected. In cases where 1,25-dihydroxy vitamin D3 is normal a vitamin D receptor defect must be taken into account.
The disease is most often caused by inadequate intake of vitamin precursors or insufficient exposure to sun light. Some rare hereditary forms are due to mutations of the vitamin D activating enzyme (type 1) or the vitamin D receptor (type 2).
Kato S et al. (2002) Molecular genetics of vitamin D- dependent hereditary rickets.[^]
Econs MJ et al. (1997) Autosomal dominant hypophosphatemic rickets/osteomalacia: clinical characterization of a novel renal phosphate-wasting disorder.[^]
et al. (2000) Autosomal dominant hypophosphataemic rickets is associated with mutations in FGF23.[^]
Scriver CR et al. (1977) Hypophosphatemic nonrachitic bone disease: an entity distinct from X-linked hypophosphatemia in the renal defect, bone involvement, and inheritance.[^]
Scriver CR et al. (1981) Autosomal hypophosphataemic bone disease responds to 1,25-(OH)2D3.[^]