An unusual cause of osteomalacia in a young lady

Oncogenic osteomalacia is a rare entity, caused by excessive secretion of fibroblast growth factor-23 (FGF-23) from the peripherally located benign tumours of mesenchymal origin. Patients usually present with chronic widespread pain and fatigue. Diagnostic approach involves demonstration of excessive urinary loss of phosphate and the high plasma level of FGF-23. Whole of PET-CT scan or whole body MRI scan are used to detect the tumour. PET/CT Ga-68 dotatate scan is required often when the other imaging modalities fail to detect the neoplasm. Here we present the case of a 32year old lady who presented to us with chronic low back pain and thorough evaluation helped us to diagnose this rare disease.