Total protein is mostly measured as part of a liver function test profile, and is not often requested in isolation. It can be used, with measurement of albumin, to calculate ‘globulins’ which may indicate activation or depletion of the immune system. So total protein measurement helps the doctor detect certain liver and kidney disorders as well as other diseases.
If your doctor thinks that you have symptoms of a liver or kidney disorder
A blood sample drawn from a vein in your arm
The total protein test measures the concentration of all 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 types of proteins, albumin and globulin. Albumin moves many small molecules through the blood 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.
A blood sample is collected by needle from a vein.
Total protein measurements can reflect someone's nutritional status, the presence of kidney disease and liver disease, as well as many other conditions. If total protein is abnormal, further tests may be needed to identify which protein fraction is abnormal, so that a specific diagnosis can be made.
Total protein is 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). It will also be requested as part of the investigation of multiple myeloma.
If total protein results are abnormal further tests will be required to identify the cause. Low total protein levels can suggest a liver disorder (the liver is an important producer of many plasma proteins), a kidney disorder (proteins may be lost from the circulation into the urine due to a kidney disorder) or a disorder in which protein is not digested or absorbed properly. Low total protein concentrations may sometimes be seen in patients with deficiency of the immune system. More specific tests, such as albumin and liver enzyme tests must be performed to make an accurate diagnosis.
Mildly higher total protein levels can be due to dehydration or infection and inflammation and high total protein levels may be due to some types of blood cancer that lead to an accumulation of an abnormal protein (such as multiple myeloma) or to long-term liver disease.
Prolonged application of a tourniquet or standing during blood collection can increase total protein levels.
Many medications may affect total protein levels, including oestrogens, steroids, and oral contraceptives. Tell your healthcare practitioner all the prescription or over-the-counter medications, supplements, or illicit substances you may be taking.
Albumin; liver function tests; protein electrophoresis
Conditions: Multiple myeloma, liver disease, kidney disorders
RCPA Manual - Protein
Medline Plus - Total Protein
Last Review Date: September 30, 2020