What is a Total Protein Test
The total protein test measures the total amount of two kinds of protein in your body: albumin and globulin. It is used as part of your routine health checkup. It may also be used if you are experiencing unexpected weight loss, fatigue, or have symptoms of a kidney or liver disease.
What Are Proteins?
Proteins are important building blocks of all cells and tissues. Proteins are necessary for your body’s growth, development, and health. Blood contains two classes of protein, albumin and globulin. Albumin proteins keep fluid from leaking out of blood vessels. Globulin proteins play an important role in your immune system.
Purpose of the Total Protein Test
A total protein test is completed as part of your routine health checkup. It is one of the tests that make up your comprehensive medical panel (CMP). It may be specifically ordered if you are experiencing unexplained weight loss, fatigue, edema, or have symptoms of kidney or liver disease.
The total protein test will take a measurement of the total amount of protein in your blood, specifically looking for the amount of albumin and globulin.
This test will also look at the ratio of albumin to globulin in your blood. This is known as the a/g ratio.
How Is the Total Protein Test Performed?
The test uses a blood sample that is analyzed in the laboratory. To obtain a blood sample, the lab technician will draw blood from a vein in your arm or the back of your hand. First, the site is cleaned with an antiseptic wipe. The lab staff will wrap a band around your arm to apply pressure to the area and gently insert the needle into the vein. The blood will collect into a tube attached to the needle. Once the tube is full, the band and the needle will be removed from your arm. Pressure should be applied to the puncture site with a cotton ball pressed to the site to stop any bleeding.
In infants or small children, a lancet is used to puncture the skin and the blood collects in a small glass pipette, test strip, or onto a slide. A bandage may be placed over the area if there is any bleeding.
Preparing for the Total Protein Test
You do not need to make any special preparations before the test is done. Your healthcare provider will let you know if you should avoid food or drinks before the test.
Many medications can affect the total protein test results. Talk to your doctor about your current medication use before you take this test.
Medications that can affect the test results include:
- growth hormone
- ammonium ions
- oral contraceptives
You may feel moderate pain or discomfort from the blood test. The risks associated with having a blood test are minimal. In some cases, you may experience:
- excessive bleeding
- fainting or feeling light-headed
- developing a hematoma (blood gathering under the skin)
- there is a risk of infection any time the skin is broken
What Do the Results Mean?
Total Protein Range
The normal range for total protein is between 6 and 8.3 gm/dL (grams per deciliter). This range may vary slightly among laboratories. These ranges also vary on other factors such as age, gender, population, and test method. Your total protein measurement may increase during pregnancy.
If total protein is abnormal, additional tests must be performed to identify which specific protein is low or high before a diagnosis can be made.
Elevated total protein may indicate:
- inflammation or infections (such as viral hepatitis B or C, HIV)
- bone marrow disorders (such as multiple myeloma or Waldenstrom’s disease)
Low total protein may indicate:
- liver disorder
- kidney disorder (such as nephrotic disorder or glomerulonephritis)
- malabsorption conditions (such as celiac disease or inflammatory bowel disease)
- extensive burns
Normally, the a/g (albumin to globulin) ratio is slightly more than one. If the ratio is too low or too high, additional testing must be done to determine the cause and diagnosis. In general, if the ratio is low it suggests autoimmune disease, multiple myeloma, cirrhosis, or kidney disease. A high ratio can indicate genetic deficiencies or leukemia.