Hypophosphatemic Osteomalacia

Diabetes phosphorus (DP) is a group of rare conditions characterized by renal phosphate leakage, leading to hypophosphatemia and osteomalacia. Although PD-related osteomalacia is much rarer than vitamin D-related osteomalacia, its etiologies are many and varied, including genetic, oncogenic and drug-related causes, as well as tubulopathies. The diagnosis of PD is primarily a biological one, based on hypophosphatemia associated with a low rate of tubular phosphorus reabsorption (TRP). Once the diagnosis has been made, a thorough etiological work-up is required to identify the underlying cause, plan treatment and prevent bone complications. This is based on biology, metabolic imaging and, if necessary, a genetic study. The main objective is to find a curable etiology, in particular an FGF-23-secreting tumour requiring surgical removal. In the absence of an identified cause, PD is said to be idiopathic. Its management is medical, based mainly on optimal phosphorus and calcitriol supplementation.