Invited Speaker ESA-SRB 2023 in conjunction with ENSA

X Linked Hypophosphatemia and Burosumab treatment in adults (#105)

Malu Alvarez 1 , Maria-Liza Nery 1 , Rory Clifton-Bligh 1 2
  1. Department of Diabetes, Endocrinology, and Metabolism, Royal North Shore Hospital, St Leonards, NSW, Australia
  2. Northern Clinical School, Sydney Medical School, University of Sydney, Camperdown, NSW, Australia

X-linked hypophosphataemic (XLH) rickets is caused by a genetic mutation of the PHEX gene which results in increased levels of fibroblast growth factor 23 (FGF23). Excess FGF23 supresses renal reabsorption of phosphate and the renal synthesis of 1,25 dihydroxy vitamin D, resulting in low
serum phosphate levels. This dysregulation of phosphate homeostasis disrupts the mineralisation and ossification of bone, causing abnormal bone development and short stature1. Individuals may experience bone and joint pain, muscular dysfunction, impaired ambulation, dental complications,
pseudofractures, early osteoarthritis, enthesopathy and hearing difficulties, in varying severity2,3 

Conventional treatment involves supplementation of phosphate and vitamin D in an attempt to normalise serum levels, but this does not target the underlying dysregulation of phosphate homeostasis. Conventional treatment is poorly tolerated and there is limited evidence of the benefits of conventional treatment in adults4.

Burosumab is a new drug treatment for XLH that has achieved favourable results in clinical trials.5,6 It is a monoclonal antibody that binds to and inhibits FGF23, thereby increasing phosphate and 1,25 dihydroxy vitamin D serum levels, leading to improvements in rickets and in growth in children
improvement in fracture healing and decreased pain and stiffness in adults.

This presentation will focus on the nursing aspects of caring for adult patients with XLH requiring Burosumab treatment: first presentation to adult clinics, assessment tools and diagnostic tests required, and the safety and administration of Burosumab.

  1. Carpenter et al. 2011
  2. Chesher et al. 2018
  3. Skrinar et al. 2019
  4. Carpenter et al. 2014
  5. Carpenter et al. 2018
  6. Insogna et al. 2018