Tumour Induced Osteomalacia: An Often-Missed Cause of Chronic Hypophosphatemia

Significant hypophosphatemia in adult is uncommon, in which the most common culprit being Vitamin D deficiency. Hypophosphatemia in adults, require proper attention as it may indicate paraneoplastic effect of mesenchymal tumour (Fibroblast growth factor 23 secreting tumour). The diagnosis of such condition at early stage, along with prompt treatment can correct hypophosphatemia and improve the patient symptomatically. Here we are presenting a case of 48 years old female who had severe hypophosphatemia and on work up found to have FGF23 secreting mesenchymal tumour of the naso-ethmoid bone, surgical removal of which corrected hypophosphatemia and showed clinical improvement.