Hyperphosphatemia phosphate-binding agents

TABLE 23-5. Phosphate-Binding Agents Used in the Treatment of Hyperphosphatemia in CKD... 

Patients with chronic renal failure develop hyperphosphatemia, hypocalcemia, secondary hyperparathyroidism, and severe metabolic bone disease. The secondary hyperparathyroidism is thought to be due to hyperphosphatemia and decreased 1, 25-(OH)2 formation. Oral or intravenous l,25-(OH)2D3 (calcitriol) therapy along with oral phosphate-binding agents and calcium supplementation is effective in reducing the effects of renal osteodystrophy. 

Management of hyperphosphatemia, calcium balance, and secondary hyperparathyroidism includes dietary phosphorus restriction, use of phosphate binding agents, and vitamin D therapy. 

Patients with CKD or ESKD often are treated for hyperphosphatemia with phosphorus-restricted diets and phosphate binding agents (see Chaps. 43 and 44). When these patients receive aggressive nutritional support, the combination of refeeding (cellular uptake of phosphorus for synthesis of body cell mass) and vigorous phosphatebinding therapy can result in hypophosphatemia. 

Therapy for hyperphosphatemia is directed toward correcting the cause of the high serum phosphate. In renal failure and in hypoparathyroidism, dietary restriction of phosphate and agents that bind phosphate in the intestine (calcium carbonate and others) are useful in lowering the serum phosphate concentrations. 

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