Normal range: 2.40 to 4.40 mg/dL

Phosphate concentration in the blood is maintained within a narrow normal range between 2.40 mg/dL and 4.40 mg/dL.

Hypophosphatemia or low blood phosphorus is indicated if phosphorus concentration lies below the normal range.

Hyperphosphatemia or high blood phosphorus is indicated if phosphorus concentration lies above the normal range.

Phosphate levels in children are usually higher than in adults due to the active growth of bones in children.

Phosphorus is both a mineral and an electrolyte, which is present in blood as organic and inorganic phosphates. Phosphates perform a number of essential roles in the body. It is critical in energy production and storage as it forms a part of the energy currency of cells (Adenosine tri, di, and monophosphates). It is also a structural component of DNA. It is essential in the functioning of nerves and muscles, and in the growth and maintenance of healthy bones. In blood, phosphates act as buffers to maintain the pH and electrolyte balance of the body.

Diet forms the main source of phosphorus. Once consumed, it is quickly absorbed by the digestive system. In the body, most of the phosphates are bound to the bones and teeth with calcium. Some of it is found in muscles and nerves, and a small amount in all cells where it forms a structural component of DNA and energy storage. Very small amounts of phosphates are normally found in circulation and these levels are measured with the serum phosphate test.

Phosphate levels in the blood are maintained within its very narrow normal concentration range by excretion of excess phosphorus through kidneys. Phosphate levels are also dependent on the levels of calcium, Vitamin D and Parathyroid Hormone in blood.

This test is performed on a blood sample. A syringe with a fine needle attached is used to withdraw blood sample from a blood vessel in your arm generally from the inner side of the elbow area. The doctor, nurse or the phlebotomist will tie an elastic band around your arm which will help the blood vessels to swell with blood and hence makes it easier to withdraw blood. You may be asked to tightly clench your fist. Once the veins are clearly visible, the area is cleaned with an antiseptic solution and then the needle is inserted into the blood vessel to collect the sample. You may feel a tiny pinprick during the procedure. Blood sample once collected is then sent to the laboratory.

There is no risk associated with the test. However, as this test involves a needle prick to withdraw the blood sample, rarely, a patient may experience increased bleeding, hematoma (blood collection under the skin) formation, bruising or infection at the site of needle prick.

An overnight fasting period is prescribed before the test. Inform the doctor about any medications you may be taking. No other preparations are required unless specified by your doctor.

Others tests that may be prescribed in case of an abnormal result in the blood Phosphorus test include: Blood Calcium Test Urine Calcium Test Vitamin D Test Electrolyte Panel Test Kidney Function Test Liver Function Test Parathyroid Hormone (PTH) Test Blood Sugar Tests

Hypophosphatemia is a condition where the blood phosphorus levels are below the normal range. This may occur due to: Severe malnutrition Alcoholism Major burns Diabetic ketoacidosis Fanconi syndrome Hyperparathyroidism (over secretion of parathyroid hormones) Hypercalcemia (high blood calcium levels) Hypokalemia (low blood potassium levels) Long term use of antacids or diuretics Long term diarrhea Deficiency of Vitamin D in children Some inherited conditions like X-linked Familial Hypophosphatemia (XLH) Certain medications like diuretics, corticosteroids, bronchodilators, etc.

Symptoms of Hypophosphatemia include: Muscular weakness Fatigue Bone pain and brittle bones Loss of appetite Irritability Numbness Confusion Slow growth in children Tooth decaynSymptoms may not appear in case of mild deficiency, but only in case of severe or chronic deficiency.

Hyperphosphatemia is the condition where blood phosphorus levels rise higher than the normal range. This may occur due to: Liver diseases Kidney failure Hypoparathyroidism (reduced secretion of parathyroid hormones) Diabetic ketoacidosis initial stage Increased phosphorus consumption in diet or through supplements

Symptoms of Hyperphosphatemia include: Muscle spasms or cramps Numbness and tingling sensation near mouth Joint pain Weak and brittle bones Rashes and itchy skin

Dietary sources form the principal source of phosphorus. Some very commonly available food items rich in phosphorus are: Animal Meat Poultry Seafood Dairy products Nuts Whole grain Beans