[A case of hypophosphatemia induced by intravenous administration of saccharated iron oxide]

An 81-year-old woman was hospitalised because of pneumonia in December 1989. In February 1991, an iliac bone biopsy was performed on the suspicion of disturbed bone metabolism due to chronic renal failure. Since she developed anemia due to continuous bleeding from the surgical wounds, saccharated iron oxide was administered beginning in March. Hypophosphatemia was noted 23 days after the beginning of administration. Due to the possibility of osteomalacia, active vitamin D was given but the hypophosphatemia persisted. Following an EDTA-2 Na load test performed to evaluate the reabsorption of phosphorus in the renal tubules, it was considered that the patient had a functional disorder of the parathyroid glands and that reabsorption of phosphorus was interrupted in the renal tubules. Furthermore, abnormal distributions of phosphorus seemed to occur in the same areas where sucrose was metabolized and iron was stored. Therefore, it was considered that these abnormalities induced hypophosphatemia following the intravenous administration of saccharated iron oxide. In addition to these actions, the possibility remained that phosphate absorption was inhibited in the small intestine by calcium lactate.