Hypophosphatemic rickets and osteomalacia

Hypophosphatemic rickets and osteomalacia.

The hypophosphatemic conditions that interfere in bone mineralization comprise many hereditary or acquired diseases, all of them sharing the same pathophysiologic mechanism: reduction in the phosphate reabsorption by the renal tubuli. This process leads to chronic hyperphosphaturia and hypophosphatemia, associated with inappropriately normal or low levels of calcitriol, causing osteomalacia or ...

199 - Osteomalacia and rickets*

1997 Vitamin D is converted in the liver by a vitamin D-25-hydroxylase (25-OHase) to form the major circulating form of vitamin D, 25-hydroxyvitamin D [25(OH)D]. There have been at least four different 25-OHases identified both in mitochrondia and in microsomes. 25(OH)D is, however, biologically inert and requires hydroxylation in the kidneys on carbon 1 by the CYP27B mitrochondrial enzyme 25-h...

Hypophosphatemic rickets with hypercalciuria.

Hereditary hypophosphatemic rickets

Hereditary hypophosphatemic rickets (HHR) are a group of diseases characterized by renal phosphate wasting causing growth retardation, rickets and osteomalacia. The most common form is the X-linked dominant hypophosphatemic rickets caused by inactivating mutations in the PHEX gene. The other hereditary hypophosphatemic syndromes present a lower prevalence. These include autosomal dominant hypop...

Rickets and osteomalacia

Although the relationship between rickets and vitamin D was recognized over 60 years ago it is only relatively recently that the metabolic pathway leading to the active form of vitamin D was recognized. We now understand that vitamin D in the form of one of its active metabolites is necessary for the maintenance of calcium homeostasis and we appreciate in part the mechanisms by which this is br...