Oncogenic Osteomalacia: A New Observation

Oncogenic osteomalacia is a rare paraneoplastic syndrome resulting from an increased secretion of a fibroblast growth factor 23 (FGF23), generally by a benign mesenchymal tumor. We report a case of a 60 years old female patient who had chronic bone pain. A Diagnosis of osteomalacia was made based on the following: difficulty walking, waddling gait, bone pain, a normal rate of calcemia PTH and of 25 OH vitamin D3 associated with an increased alkaline phosphatase rate, hypophosphoremia and a decrease in the rate of tubular reabsorption of phosphates. The neoplastic origin was suspected in the presence of a biological inflammatory syndrome and was confirmed by a high level of FGF23. The tumor could not be located and the patient received calcitriol and phosphorus.