Hypophosphatemia is too much phosphate in the blood (hyper means 'too much'). Phosphate is the naturally occurring form of phosphorus, a substance that the body requires for bone and cell formation, genetic coding, and energy metabolism; however, the levels of phosphate are usually regulated in the body. A normal range of phosphate is between 0.81 mmol /L and 1.45 mmol /L. Similar to calcium, vitamin D is required to properly absorb phosphate .
16573501028700 Fig: Chemic al Structure of Phosphate Group
Most people with high phosphate levels don't have symptoms. In some person with chronic kidney disease high phosphate levels cause calcium levels in the blood to drop.
Symptoms of low calcium include:
muscle cramps or spasms
numbness and tingling around the mouth
bone and joint pain
The level of phosphorus may increase due to number of factors. Normal quantity of this element is necessary for metabolic function and balancing cellular activities.
Kidney failure or any type of kidney disease can cause hyperphosphatemia. Kidneys play a vital role in excreting excess amount of phosphorous from the body and the problem arises when it cannot perform well. This leads to accumulation of phosphorus in blood.
Severe injury or trauma or burns can cause cellular injury leading to increase in phosphorus content. In case the person has taken large amounts of bisphosphonate or vitamin D it can cause hyperphosphatemia.
Chronic condition of diabetes and prolonged use of alcohol can cause this disorder. If the levels of thyroid hormone change the function of kidney may get reduced directly. For instance, low levels of parathyroid can induce increased re-uptake of phosphate causing excess of phosphorus. Tumor lysis syndrome will directly cause increased phosphate level.
Complications of Hyperphosphatemia
Short Term Complications of Hyperphosphatemia:
These include acute hypocalcaemia, tetany, deposition of calcium and phosphate in bone joints, subcutaneous tissues and soft tissues, and chronic kidney disease.
Long Term Complications of Hyperphosphatemia :
Long term complications of hyperphosphatemia are much severe most of which are irreversible. These include renal failure; organ damage; damage to vascular system; bone, skin and heart complication. If present over prolonged period of time, it increases the risk of developing cardio vascular issues. Hyperphosphatemia is one of the causes of mortality in patients with the history of kidney transplant, end stage renal disease and chronic kidney issues.
Diagnosis of hyperphosphatemia includes a full chemistry profile as follows:
Decreased Calcium Level with Increased Phosphate Level: This is commonly associated with renal failure, hypoparathyroidism and pseudohypoparathyroidsm.
Determining BUN (Blood Urea Nitrogen) and Creatinine Levels: These help in understanding whether hyperphosphatemia is caused by renal failure or not.
Parathyroid Hormones (PTH) above Normal Limits : This is common in patients with pseudo-hypothyroidism and renal failure.
Low Levels of Parathyroid Hormones (PTH) with Normal Renal Functions : Common in individuals with primary or acquired hypoparathyroidism.
45720046291500 Hyperphosphatemia with Chronic Kidney Disease
Fig: Phosphate Homeostasis in Humans
If our kidneys are damaged, we can lower high blood phosphate levels in three ways:
reduce the amount of phosphate in your diet
remove extra phosphate with dialysis
lower the amount of phosphate your intestines absorb using medicine
First, limit foods that are high in phosphorous, such as:
chicken and other types of poultry
In addition to diet and dialysis, you'll probably need medicine to help your body remove excess phosphate. A few drugs help reduce the amount of phosphate your intestines absorb from foods you eat. These include:
Calcium-based phosphate binders (calcium acetate and calcium carbonate)
Sevelamer hydrochloride (Renagel)
Hyperphosphatemia is often a complication of chronic kidney disease. One way to reduce your risk is by slowing kidney damage. Protect your kidneys by treating the cause of your kidney disease.
High blood pressure can weaken the blood vessels that supply oxygen-rich blood to your kidneys. Taking high blood pressure medicines like angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers can