{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:28:48Z","timestamp":1772252928240,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,15]],"date-time":"2021-06-15T00:00:00Z","timestamp":1623715200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>The authors present a stereotypical case presentation of X-linked hypophosphatemia (XLH) and provide a review of the pathophysiology and related pharmacology of this condition, primarily focusing on the FDA-approved medication burosumab. XLH is a renal phosphate wasting disorder caused by loss of function mutations in the PHEX gene (phosphate-regulating gene with homologies to endopeptidases on the X chromosome). Typical biochemical findings include elevated serum levels of bioactive\/intact fibroblast growth factor 23 (FGF23) which lead to (i) low serum phosphate levels, (ii) increased fractional excretion of phosphate, and (iii) inappropriately low or normal 1,25-dihydroxyvitamin D (1,25-vitD). XLH is the most common form of heritable rickets and short stature in patients with XLH is due to chronic hypophosphatemia. Additionally, patients with XLH experience joint pain and osteoarthritis from skeletal deformities, fractures, enthesopathy, spinal stenosis, and hearing loss. Historically, treatment for XLH was limited to oral phosphate supplementation, active vitamin D supplementation, and surgical intervention for cases of severe bowed legs. In 2018, the United States Food and Drug Administration (FDA) approved burosumab for the treatment of XLH and this medication has demonstrated substantial benefit compared with conventional therapy. Burosumab binds circulating intact FGF23 and blocks its biological effects in target tissues, resulting in increased serum inorganic phosphate (Pi) concentrations and increased conversion of inactive vitamin D to active 1,25-vitD.<\/jats:p>","DOI":"10.3390\/life11060563","type":"journal-article","created":{"date-parts":[[2021,6,15]],"date-time":"2021-06-15T11:00:33Z","timestamp":1623754833000},"page":"563","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Metabolic Bone Disease X-linked Hypophosphatemia: Case Presentation, Pathophysiology and Pharmacology"],"prefix":"10.3390","volume":"11","author":[{"given":"Jon","family":"Vincze","sequence":"first","affiliation":[{"name":"College of Osteopathic Medicine Division of Biomedical Science, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"},{"name":"Bone & Muscle Research Group, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Brian W.","family":"Skinner","sequence":"additional","affiliation":[{"name":"College of Osteopathic Medicine Division of Clinical Sciences Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Katherine A.","family":"Tucker","sequence":"additional","affiliation":[{"name":"Leighton School of Nursing, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kory A.","family":"Conaway","sequence":"additional","affiliation":[{"name":"College of Osteopathic Medicine Division of Biomedical Science, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"},{"name":"Bone & Muscle Research Group, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9942-2945","authenticated-orcid":false,"given":"Jonathan W.","family":"Lowery","sequence":"additional","affiliation":[{"name":"College of Osteopathic Medicine Division of Biomedical Science, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"},{"name":"Bone & Muscle Research Group, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Julia M.","family":"Hum","sequence":"additional","affiliation":[{"name":"College of Osteopathic Medicine Division of Biomedical Science, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"},{"name":"Bone & Muscle Research Group, Marian University, 3200 Cold Spring Rd., Indianapolis, IN 46222, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1027","DOI":"10.1038\/ki.1996.149","article-title":"Renal Na(+)-phosphate cotransporter gene expression in X-linked Hyp and Gy mice","volume":"49","author":"Tenenhouse","year":"1996","journal-title":"Kidney Int."},{"key":"ref_2","first-page":"1351","article-title":"Fine structure mapping of the human X-linked hypophosphatemic rickets gene locus","volume":"79","author":"Econs","year":"1994","journal-title":"J. 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