CC BY 4.0 · Osteologie 2020; 29(04): 293-301
DOI: 10.1055/a-1257-8108
Originalarbeit

Diagnostik und Therapie der hypophosphatämischen Rachitis im Kindesalter

Hypophosphatemic Rickets: Diagnostic Approach and current Treatments in Childhood
Jakob Höppner
1   Centrum für seltene Erkrankungen Ruhr, Ruhr-Universität Bochum und Universität Witten/Herdecke, Bochum, Deutschland
,
Uwe Kornak
2   Institut für Humangenetik, Universitätsmedizin Göttingen, Deutschland
,
Wolfgang Högler
3   Univ.-Klinik für Kinder- und Jugendheilkunde, Johannes Kepler Universität Linz, Kepleruniversitätsklinikum, Linz, Österreich
,
Barbara Obermayer-Pietsch
4   Klinische Abteilung Endokrinologie und Diabetologie, Universitätsklinik für Innere Medizin, Medizinische Universität Graz, Österreich
,
Frank Rutsch
5   Allgemeine Pädiatrie, Klinik für Kinder- und Jugendmedizin und Centrum für seltene Erkrankungen, Universitätsklinikum Münster, Deutschland
,
Ralf Oheim
6   Institut für Osteologie und Biomechanik, Universitätsklinikum Hamburg-Eppendorf, Deutschland
,
Corinna Grasemann
1   Centrum für seltene Erkrankungen Ruhr, Ruhr-Universität Bochum und Universität Witten/Herdecke, Bochum, Deutschland
7   Klinik für Kinder- und Jugendmedizin, St. Josef-Hospital, Universitätsklinikum der Ruhruniversität Bochum, Deutschland
› Institutsangaben

Zusammenfassung

Die Rachitis im Kindes- und Jugendalter beruht auf einer Unterversorgung des wachsenden Körpers mit Kalzium und/oder Phosphat. Der Kalzium-Phosphat-Stoffwechsel unterliegt einer komplexen hormonellen Regulation durch Calcitriol, Parathormon und dem ‚Fibroblast Growth Factor 23‘(FGF23).

Eine unphysiologische Überproduktion von FGF23 führt durch resultierenden renalen Phosphatverlust zu einem Phosphatmangel, mit der Folge der Untermineralisation von Knochen, Zähnen und Wachstumsfugen und damit zur hypophosphatämischen Rachitis (HR) bzw. Osteomalazie. Die häufigste Form der FGF23-abhängigen HR ist die X-chromosomale hypophosphatämische Rachitis (XLH). Im Kindesalter steht, neben einer Substitution von Phosphat und aktivem Vitamin D, mit Burosumab seit 2018 ein monoklonaler Antikörper gegen FGF23 für die Therapie der XLH zur Verfügung. Diese Therapie hat das Potenzial, Langzeitkomplikationsraten, Wachstum und Lebensqualität substanziell zu verbessern, entsprechende Langzeitdaten werden daher in Registern gesammelt.

Möglichkeiten zur Vernetzung mit Betroffenen bieten die Vereine Phosphatdiabetes e.V. und www.phosphatdiabetes.at.

Abstract

Rickets is caused by an undersupply of calcium and/or phosphate to the growing body. The calcium-phosphate metabolism is regulated by the secosteroid hormone calcitriol, parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23).

Excessive FGF23 action results in reduced renal phosphate reabsorption, and subsequent hypophosphataemia, undermineralization of bone, teeth and growth plates and the phenotype of hypophosphatemic rickets (HR)/osteomalacia. The most common form of FGF23-dependent HR is X-linked hypophosphatemic rickets (XLH), which was traditionally treated via supplementation of phosphate and active vitamin D only. Since 2018, a monoclonal antibody against FGF23, Burosumab, is available for the therapy of XLH in children. The new therapy has the potential to improve long-term complications, growth and quality of life; such data are currently being collected in registries. Support groups for German-speaking people affected by XLHinclude Phosphatdiabetes e.V. and www.phosphatdiabetes.at.



Publikationsverlauf

Artikel online veröffentlicht:
23. November 2020

© 2020. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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