The effects of phosphate and vitamin D therapy on osteopenic, hypophosphatemic osteomalacia of childhood

Two severely osteopenic adolescent males with clinical manifestations of adult onset hypophosphatemic osteomalacia were resistant respectively to physiological and pharmacological doses of vitamin D. Clinical improvement ensued following initiation of pharmacological doses of vitamin D and phosphate. Non decalcified bone biopsies obtained before and during therapy exhibited correction of an isolated mineralization defect in the one patient and promotion of bone collagen production and mineralization in the second. The response to treatment was reflected in striking changes in tetracycline labeled calcification fronts in both patients.