At a Glance
Why Get Tested?
To screen for certain liver and kidney disorders as well as other diseases
When to Get Tested?
If your doctor thinks that you have symptoms of a liver or kidney disorder
Sample Required?
A blood sample drawn from a vein in your arm
The Test Sample
What is being tested?
The total protein test is a rough measure of all of the proteins in the plasma portion of your blood. Proteins are important building blocks of all cells and tissues; they are important for body growth and health. Total protein measures the combined amount of two classes of proteins, albumin and globulin. Albumin is a carrier of many small molecules, but its main purpose is to keep fluid from leaking out of blood vessels, while globulin proteins include enzymes, antibodies, and more than 500 other proteins.
How is the sample collected for testing?
A blood sample is collected by needle from a vein.
The Test
How is it used?
Total protein measurements can reflect nutritional status, kidney disease, liver disease, and many other conditions. If total protein is abnormal, further tests must be performed to identify which protein fraction is abnormal, so that a specific diagnosis can be made.
When is it requested?
Total protein may be measured along with several other tests to provide information if you have symptoms that suggest a liver or kidney disorder, or to investigate the cause of abnormal pooling of fluid in tissue (oedema).
What does the test result mean?
Low total protein levels can suggest a liver disorder, a kidney disorder, or a disorder in which protein is not digested or absorbed properly. More specific tests, such as albumin and liver enzyme tests, must be performed to make an accurate diagnosis. High total protein levels can indicate dehydration or some types of cancer that lead to an accumulation of an abnormal protein (such as multiple myeloma).
Is there anything else I should know?
Prolonged application of a tourniquet during blood collection can increase total protein levels. Drugs that may increase protein levels include anabolic steroids, androgens, growth hormone, insulin, and progesterone. Drugs that may decrease protein levels include oestrogens and oral contraceptives.
Common Questions
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Article Sources
NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.
