Hyperphosphatemia

Signs and symptoms include ectopic calcification, secondary hyperparathyroidism, and renal osteodystrophy. Abnormalities in phosphate metabolism such as hyperphosphatemia are included in the definition of the new chronic kidney disease–mineral and bone disorder (CKD–MBD). ==Causes==

Hypoparathyroidism: In this situation, there are low levels of parathyroid hormone (PTH). PTH normally inhibits reabsorption of phosphate by the kidney. Therefore, without enough PTH there is more reabsorption of the phosphate leading to a high phosphate level in the blood. Chronic kidney failure: When the kidneys are not working well, there will be increased phosphate retention. Drugs: hyperphosphatemia can also be caused by taking oral sodium phosphate solutions prescribed for bowel preparation for colonoscopy in children. ==Diagnosis==

The diagnosis of hyperphosphatemia is made through measuring the concentration of phosphate in the blood. A phosphate concentration greater than 1.46 mmol/L (4.5 mg/dL) is indicative of hyperphosphatemia, though further tests may be needed to identify the underlying cause of the elevated phosphate levels. It is considered significant when levels are greater than 1.6 mmol/L (5 mg/dL). ==Treatment==

High phosphate levels can be avoided with phosphate binders and dietary restriction of phosphate. Previously aluminum hydroxide was the medication of choice, but its use has been largely abandoned due to the increased risk of aluminum toxicity. ==References==