Proteins are important building blocks of all cells and tissues; they are important for body growth, development, and health. They form the structural part of most organs and make up enzymes and hormones that regulate body functions.
Two classes of proteins are found in the blood, albumin and globulin. Albumin makes up about 60% of the total protein. The remaining 40% of proteins in the plasma are referred to as globulins. The globulin proteins are a heterogeneous group. They include enzymes, antibodies, hormones, carrier proteins, and numerous other types of proteins.
The level of total protein in the blood is normally a relatively stable value, reflecting a balance in loss of old protein molecules and production of new protein molecules.
Total protein may decrease in conditions:
- Where production of albumin or globulin proteins is impaired, such as malnutrition or severe liver disease
- That accelerate the breakdown or loss of protein, such as kidney disease (nephrotic syndrome)
- That increase/expand plasma volume (diluting the blood), such as congestive heart failure
Total protein may increase with conditions that cause:
- Abnormally high production of protein (e.g., inflammatory disorders, multiple myeloma)
Why it is done?
Total protein may also be ordered to provide general information about a person's nutritional status, such as when someone has undergone a recent, unexplained weight loss. It can be ordered along with several other tests to provide information when someone has symptoms that suggest a liver, kidney, or bone marrow disorder, or to investigate the cause of abnormal pooling of fluid in tissue (edema).
What the total protein results may indicate
Results of a total protein test are usually considered along with those from other tests of the CMP and will give the doctor information on a person's general health status with regard to nutrition and/or conditions involving major organs, such as the kidney and liver.
- A low total protein level can suggest a liver disorder, a kidney disorder, or a disorder in which protein is not digested or absorbed properly. Low levels may be seen in severe malnutrition and with conditions that cause malabsorption, such as celiac disease or inflammatory bowel disease (IBD).
- A high total protein level may be seen with chronic inflammation or infections such as viral hepatitis or HIV. It also may be associated with bone marrow disorders such as multiple myeloma.