[Biopsychosocial care concept for children with X‑chromosomal hypophosphatemia (XLH) : Example of the multiprofessional approach of social pediatric centers].

Patients with severe, rare and complex diseases require the multiprofessional biopsychosocial care concept of a social pediatric center for chronically ill children and adolescents. The care concept is illustrated using the example of the multiorgan disease X‑chromosomal hypophosphatemic rickets (XLH), the most common congenital form of rickets.The disease is based on inactivating mutations in the Phosphate-regulating gene with Homologies to Endopeptidases on the X‑chromosome (PHEX) gene, which leads to an increased synthesis and secretion of fibroblast growth factor 23 (FGF23). FGF23 plays an important role in phosphate homeostasis. High FGF23 concentrations lead to severe hypophosphatemia via renal phosphate loss, resulting in significant mineralization disorders of the skeletal system and teeth. Until recently, only conventional drug therapy consisting of phosphate and active vitamin D was available. Now, the neutralizing FGF23 antibody can be used for a targeted therapy of the disease. The multiprofessional care concept consists of numerous medical specialists and a psychosocial team. The aim of the care concept is to enable patients with their severe chronic disease to participate in everyday life in an age-appropriate manner. The continuation of care in adulthood must be ensured by an implemented transition.