Debilitating Pain and Fractures

A Rare Case of Hypophosphatemic Osteomalacia with Concomitant Vitamin D Deficiency in Neurofibromatosis Type 1

  • Shamharini Nagaratnam University Kebangsaan Malaysia Medical Centre (UKMMC)
  • Malathi Karupiah University Kebangsaan Malaysia Medical Centre (UKMMC)
  • Norlaila Mustafa University Kebangsaan Malaysia Medical Centre (UKMMC)
Keywords: NF1, hypophosphatemia, osteomalacia, FGF23, vitamin D deficiency


Hypophosphatemic osteomalacia is a rare form of metabolic bone disorder in neurofibromatosis type 1 (NF1). The exact disease mechanism of this disorder in NF1 is yet to be established. We present a 44-year-old female known to have NF1, who presents with debilitating bone pain, weakness and multiple fractures. Laboratory investigations showed
persistent hypophosphatemia with renal phosphate wasting suggestive of hypophosphatemic osteomalacia. She also had concomitant vitamin D deficiency which contributed to the disease severity. Medical therapy with oral phosphate and vitamin D improved her symptoms without significant changes in fracture healing or phosphate levels.


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Author Biographies

Shamharini Nagaratnam, University Kebangsaan Malaysia Medical Centre (UKMMC)

Endocrine Fellow, Endocrine Unit, Department of Medicine

Malathi Karupiah, University Kebangsaan Malaysia Medical Centre (UKMMC)

Department of Medicine


Norlaila Mustafa, University Kebangsaan Malaysia Medical Centre (UKMMC)

Head of Department of Medicine,

Consultant Physician and Endocrinologist,

Endocrine Unit, Department of Medicine


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How to Cite
Nagaratnam, S., Karupiah, M., & Mustafa, N. (2020). Debilitating Pain and Fractures: A Rare Case of Hypophosphatemic Osteomalacia with Concomitant Vitamin D Deficiency in Neurofibromatosis Type 1. Journal of the ASEAN Federation of Endocrine Societies, 35(1). Retrieved from