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GENERAL CONSIDERATIONS
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Advanced CKD with decreased urinary excretion of phosphate is the most common cause of hyperphosphatemia. Other causes are listed in Table 21–9.
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A. Symptoms and Signs
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The clinical manifestations are those of the underlying disorder or associated condition.
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B. Laboratory Findings
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In addition to elevated phosphate, blood chemistry abnormalities are those of the underlying disease.
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Treatment is directed at the underlying cause. Exogenous sources of phosphate, including enteral or parenteral nutrition and medications, should be reduced or eliminated. Dietary phosphate absorption can be reduced by oral phosphate binders, such as calcium carbonate, calcium acetate, sevelamer carbonate, lanthanum carbonate, and aluminum hydroxide. Sevelamer, lanthanum, and aluminum may be used in patients with hypercalcemia, although aluminum use should be limited to a few days because of the risk of aluminum accumulation and neurotoxicity. In acute kidney injury and advanced CKD, dialysis will reduce serum phosphate.
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Patients with acute severe hyperphosphatemia require hospitalization for emergent therapy, possibly including dialysis. Concomitant illnesses, such as acute kidney injury or cell lysis, may necessitate admission.
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Criscuolo
M
et al. Tumor lysis syndrome: review of pathogenesis, risk factors and management of a medical emergency. Expert Rev Hematol. 2016;9(2):197–208.
[PubMed: 26629730]
+
Felsenfeld
AJ
et al. Pathophysiology of calcium, phosphorus, and magnesium dysregulation in chronic kidney disease. Semin Dial. 2015 Nov–Dec;28(6):564–77.
[PubMed: 26303319]
+
Ketteler
M
et al. Treating hyperphosphatemia—current and advancing drugs. Expert Opin Pharmacother. 2016 Oct;17(14):1873–9.
[PubMed: 27643443]
+
Leaf
DE
et al. A physiologic-based approach to the evaluation of a patient with hyperphosphatemia. Am J Kidney Dis. 2013 Feb;61(2):330–6.
[PubMed: 22938849]