| Diminished supply or absorption Starvation Parenteral alimentation with inadequate phosphate content Malabsorption syndrome, small bowel bypass Absorption blocked by oral antacids with aluminum or magnesium Vitamin D–deficient and vitamin D–resistant osteomalacia Increased loss Phosphaturic drugs: theophylline, diuretics, bronchodilators, corticosteroids Hyperparathyroidism (primary or secondary) Hyperthyroidism Renal tubular defects with excessive phosphaturia (congenital, Fanconi syndrome induced by monoclonal gammopathy, heavy metal poisoning), alcoholism Hypokalemic nephropathy Inadequately controlled diabetes mellitus Hypophosphatemic rickets Phosphatonins of oncogenic osteomalacia (eg, FGF23 production) Intracellular shift of phosphorus Administration of glucose Anabolic steroids, estrogen, oral contraceptives, beta-adrenergic agonists, xanthine derivatives Hungry bone syndrome Respiratory alkalosis Salicylate poisoning Electrolyte abnormalities Hypercalcemia Hypomagnesemia Metabolic alkalosis Abnormal losses followed by inadequate repletion Diabetes mellitus with acidosis, particularly during aggressive therapy Recovery from starvation or prolonged catabolic state Chronic alcoholism, particularly during restoration of nutrition; associated with hypomagnesemia Recovery from severe burns |