Tumorous phosphaturic osteomalacia. Report of a case associated with multiple hemangiomas of bone.

A case of osteomalacia associated with hypophosphatemia, decreased tubular reabsorption of phosphorus, hyperphosphaturia and renal glycosuria with associated bone pain and myopathy is presented. The patient was found to have multiple osteolytic lesions of bone which, on biopsy, proved to be sclerosing hemangiomas of bone. Treatment with oral phosphate and vitamin D effected a diminution in his symptoms of bone pain and muscular weakness. The literature on hypophosphatemic phosphaturic osteomalacia associated with mesenchymal tumors is reviewed. It has been suggested that certain mesenchymal tumors elaborate a yet to be identified humoral substance which decreased synthesis of 1 alpha, 25-dihydroxycholecalciferol causing decreased tubular reabsorption of phosphorus, hyperphosphaturia, hypophosphatemic osteomalacia and hypophosphatemic myopathy.