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Phosphorus blood test
Phosphorus - serum; HPO4 -2 ; PO4 -3 ; Inorganic phosphate; Serum phosphorus
The phosphorus blood test measures the amount of phosphate in the blood.
How the Test is Performed
A blood sample is needed.
Blood sample
Venipuncture is the collection of blood from a vein. It is most often done for laboratory testing.
How to Prepare for the Test
Your health care provider may tell you to temporarily stop taking medicines that may affect the test. These medicines include water pills (diuretics), antacids, and laxatives.
DO NOT stop taking any medicine before talking to your provider.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.
Why the Test is Performed
Phosphorus is a mineral the body needs to build strong bones and teeth. It is also important for nerve signaling and muscle contraction.
This test is ordered to see how much phosphorus is in your blood. Kidney, liver, and certain bone diseases can cause abnormal phosphorus levels.
Normal Results
Normal values range from 2.4 to 4.1 mg/dL.
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
A higher than normal level (hyperphosphatemia) may be due to many different health conditions. Common causes include:
-
Diabetic ketoacidosis
(life-threatening condition that may occur in people with diabetes)
Diabetic ketoacidosis
Diabetic ketoacidosis is a life-threatening problem that affects people with diabetes. It occurs when the body cannot use sugar (glucose) as a fuel ...
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Hypoparathyroidism
(parathyroid glands do not make enough of their hormone)
Hypoparathyroidism
Hypoparathyroidism is a disorder in which the parathyroid glands in the neck do not produce enough parathyroid hormone (PTH).
ImageRead Article Now Book Mark Article -
Kidney failure
Kidney failure
Acute kidney failure is the rapid (less than 2 days) loss of your kidneys' ability to remove waste and help balance fluids and electrolytes in your b...
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Liver disease
Liver disease
The term "liver disease" applies to many conditions that stop the liver from working or prevent it from functioning well. Abdominal pain, yellowing ...
ImageRead Article Now Book Mark Article - Too much vitamin D
- Too much phosphate in your diet
- Use of certain medicines such as laxatives that have phosphate in them
A lower than normal level (hypophosphatemia) may be due to:
- Alcoholism
- Hypercalcemia (too much calcium in the body)
-
Hyperparathyroidism
(parathyroid glands make too much of their hormone)
Hyperparathyroidism
Hyperparathyroidism is a disorder in which the parathyroid glands in your neck produce too much parathyroid hormone (PTH).
ImageRead Article Now Book Mark Article - Too little dietary intake of phosphate
- Very poor nutrition
-
Too little vitamin D, resulting in bone problems such as
rickets
(childhood) or
osteomalacia
(adult)
Rickets
Rickets is a disorder caused by a lack of vitamin D, calcium, or phosphate. It leads to softening and weakening of the bones.
ImageRead Article Now Book Mark ArticleOsteomalacia
Osteomalacia is softening of the bones. It most often occurs because of a problem with vitamin D, which helps your body absorb calcium. Your body n...
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Risks
Veins and arteries vary in size from one person to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling lightheaded
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
References
Leone KA. Calcium, magnesium, and phosphorus. In: Adams JG, ed. Emergency Medicine: Clinical Essentials . 2nd ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 166.
Yu SLA. Disorders of magnesium and phosphorous. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 119.
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Blood test - illustration
Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.
Blood test
illustration
-
Blood test - illustration
Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.
Blood test
illustration
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Viral hepatitis
(Alt. Medicine)
-
Vitamin D
(Alt. Medicine)
-
Cirrhosis
(Alt. Medicine)
-
Hemophilia
(Alt. Medicine)
-
Peptic ulcer
(Alt. Medicine)
-
Hyperparathyroidism
(Alt. Medicine)
-
Hypoparathyroidism
(Alt. Medicine)
Review Date: 11/1/2015
Reviewed By: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
