What Are Abnormal Levels of Phosphorus in Renal Failure?

Kidney failure occurs when the kidneys cannot filter wastes and excess fluids from the blood. When waste products and excess fluids build up in the blood, mineral and electrolyte imbalances can occur.

Identification

• The normal amount of blood phosphorus is 2.4 to 4.1 mg/dL (milligrams per deciliter), according to the National Institutes of Health. The serum phosphorus blood test identifies phosphorus levels outside this normal range.

Causes

• Normal kidneys control the amount of phosphorus in the blood. When the kidneys do not excrete enough phosphorus in the urine, blood phosphorus levels increase.

Significance

• High levels of phosphorus in the blood (hyperphosphatemia) can cause the body to produce too much parathyroid hormone (hyperparathyroidism). Hyperphosphatemia also contributes to low blood calcium levels (hypocalcemia) and bone changes (renal osteodystrophy), according to the Merck Manual for Healthcare Professionals.

Treatment

• Oral phosphate binders reduce the amount of phosphorus that enters the blood by binding with phosphates and eliminating them in the stool. Types of phosphate binders include calcium-based binders, aluminum-based binders and binders that do not contain aluminum or calcium.

Prevention

• Kidney disease patients can follow a low-phosphorus diet to prevent the accumulation of phosphorus in the blood. This diet limits foods high in phosphorus, such as potatoes, cola soft drinks, dairy products, dried beans and peas, nuts and canned salmon.