Bone Abstracts

Background and objectives: X-linked hypophosphatemic rickets (XLH) is the most common form of inheritable rickets. The treatment of rickets is monitored via laboratory tests such as alkaline phosphatase (ALP), clinical features, and plain X-rays. The objectives of this study were to describe the MRI features in XLH and to look for correlations between those features and XLH activity.Study design: Twenty-seven patients (younger than 18 years with XLH due ...

Many of our assumptions concerning oral implant osseointegration are extrapolated from experimental models studying skeletal tissue repair in long bones rather than in oral bones. This discrepancy between clinical practice and experimental research hampers our understanding on how alveolar bone forms or resorbs around implants and how osseointegration of oral implants can be improved. To overcome this disconnect, we have developed a mouse model which mimics oral implant placem...

Mutations in the PHEX gene cause X-linked familial hypophosphatemic rickets (XLH) with severe bone (osteomalacia) and tooth abnormalities being the distinguishing features of this disease. The PHEX mutations lead to an increase in ASARM peptides (acidic serine- and aspartate-rich motif) and osteopontin fragments which inhibit bone extracellular matrix mineralization. MEPE-derived ASARM has been shown to accumulate in tooth dentin of patients with XLH where it may impair dentin...

Mutations in PHEX and specific missense mutations of FGF23 result in elevated circulating FGF23 and hypophosphatemic rickets, respectively X-linked hypophosphatemic rickets (XLHR) and autosomal dominant HR (ADHR). FGF23, secreted by osteoblasts and osteocytes, regulates phosphate handling and vitamin D metabolism through its action on kidney. Extra renal effects of FGF23, including bone, have been very recently suspected mainly from overexpression or underexpression of FGF23 i...

Background and aim: Burosumab is a monoclonal antibody against anti-FGF23, which has been recently approved for treatment of X-linked hypophosphatemia (XLH). Beyond clinical trials, little is known about its efficacy/safety in clinical practice which is the aim of study.Patients/Methods: 39 children with XLH were switched from conventional therapy to burosumab (starting dose 0.4 mg/kg), because of following indications: non-responder to conventional ther...