Genetische Störungen der Knochenmineralisation

Zusammenfassung

Angeborene Störungen im Vitamin-D-Metabolismus und/oder in der Regulation der Phosphathomöostase führen zu einer gestörten Mineralisation des Skelettsystems. Durch das herabgesetzte Kalzium-Phosphat-Produkt bildet sich im Kindesalter eine Rachitis aus, bei Erwachsenen eine Osteomalazie. Klinische Symptome sind zumeist Extremitätenfehlstellungen (Genua vara/Genua valga), aber auch Knochenschmerzen, progrediente Muskelschwäche, Tetanie. Besonders in den vergangenen Jahren sind neue genetische Ursachen von Störungen im Phosphatstoffwechsel publiziert worden. Dieses Review beschreibt Klinik und Pathophysiologie der derzeit bekannten Ursachen angeborener Störungen des Vitamin-D-Stoffwechsels sowie der Phosphathomö ostase und zeigt mögliche zukünftige medikamentöse Optionen in der Behandlung von Patienten mit hypophosphatämischer Rachitis auf.

Summary

Hereditary disorders in vitamin D metabolism and/or in the regulation of phosphate homeostasis resulted in impaired bone mineralisation. The abnormal mineralisation of the skeleton leads to rickets in children and to osteomalacia in adults. Leading symptoms in impaired mineralisation are mostly bone deformities, but also bone pain, slow motor development, progressive muscle weakness, neuromuscular irritability or convulsions. Over the last decade our knowledge especially of the regulation of phosphorus metabolism has expended. This overview describes clinical and pathophysiological conditions of various hereditary disorders of vitamin D metabolism and phosphate homeostasis including data about possible future therapeutic strategies.

Schlüsselwörter

Vitamin-D-25-Hydroxylase-Mangel - Vitamin-D-abhängige Rachitis Typ I und II (VDAR I/II) - hypophosphatämische Rachitis

Keywords

Vitamin D-25-Hydroxylase deficiency - vitamin D-dependent rickets type I/II - hypophosphataemic rickets

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