Contributed by – Healthians Team
What is the globulin test?
A globulin test (also called globulin electrophoresis), is a test that measures the levels of a group of proteins called globulin that is present in the bloodstream. Globulin proteins are important to liver and kidney functions and help transport nutrients and fight infections. Measuring your globulin levels can give insight into how well the liver and kidneys are functioning.
There are four categories of globulin proteins: Alpha 1, Alpha 2, beta, and gamma globulin proteins. Just as there are different forms of globulins, similarly there are two different types of globulin tests. The tests are used to distinguish one category of globulin from the other and determine their ratio within the bloodstream.
Let’s look at the two tests used to determine if the globulin levels are where they should be:
- Total protein test: This test measures two classes of proteins in blood: globulin and albumin. Low protein levels can signal liver or kidney disease. If total protein is abnormal, your doctor may recommend further follow-up tests.
- Serum protein electrophoresis (SPEP): This test measures gamma globulins and other proteins in your blood. An increase in gamma globulin proteins can indicate disorders of the immune system and a type of cancer called multiple myeloma.
Who should get a Globulin test?
Your doctor may advise a Globulin test as part of a comprehensive metabolic panel (CMP) when you have a routine health check-up. The test may also be ordered if he is specifically concerned about your liver or kidney function or you have signs and symptoms, such as:
- Unexplained weight loss
- Yellow skin (Jaundice)
- Fatigue
- Swelling or fluid build-up (edema)
- Loss of appetite
Why is the Globulin test needed?
Apart from liver and kidney disorders, the globulin test may be administered to diagnose anyone of the above conditions, including:
- Malnutrition or malabsorption
- Disorders of the immune system
- Certain forms of cancer
What does a Globulin test result mean?
Normal Result:
Normal value ranges are:
- Serum globulin: 2.0 to 3.5 grams per deciliter (g/dL) or 20 to 35 grams per liter (g/L)
- IgM component: 75 to 300 milligrams per deciliter (mg/dL) or 750 to 3,000 milligrams per liter (mg/L)
- IgG component: 650 to 1,850 mg/dL or 6.5 to 18.50 g/L
- IgA component: 90 to 350 mg/dL or 900 to 3,500 mg/L
Some lab-to-lab variability in reference ranges may occur due to differences in equipment, techniques, and chemicals used.
* Gamma globulins include various types of antibodies such as immunoglobulins (Ig) M, G, and A.
What Abnormal Results Mean
Table1. A high or low total globulin level may point out to the following conditions:
|
Increased total globulin level |
Decreased total globulin level |
| Acute infection | Congenital immune deficiency |
| Blood and bone marrow cancers | Kidney disease |
|
Hyper-immunisation |
Malnutrition |
| Chronic inflammatory disease |
Acute dehydration |
A high or low total Serum protein electrophoresis (SPEP) may point out to the following conditions:
Alpha-1 abnormalities are usually due to alpha-1 antitrypsin changes.
- Decreased levels in congenital alpha-1-antitrypsin deficiency.
- Increases are found in acute inflammatory disorders (it is an acute phase reactant).
Alpha-2 abnormalities mainly involve alpha-2 macroglobulin and haptoglobin.
- Alpha-2 macroglobulin rises in nephrotic syndrome.
- Haptoglobin levels increase in inflammation and decrease with haemolytic reactions.
How is the Globulin test done?
Globulin testing is done by drawing a blood sample from a vein. In new-borns, blood draws are sometimes done as a heel stick collection.
Before the test, you may have to avoid eating and drinking for several hours or overnight. Some drugs can change the protein levels in your blood. Your health care provider may instruct you to stop taking medications that affect the test. It’s a good idea to drink extra water the day before your blood draw. When the body is properly hydrated, veins allow easier access.
