What is a globulin test?
Globulins are a group of proteins in your blood. They are made in your liver by your immune system. Globulins play an important role in liver function, blood clotting, and fighting infection. There are four main types of globulins. They are called alpha 1, alpha 2, beta, and gamma. Just as there are different types of globulins, there are different types of globulin tests. These include:
- Total protein test. This blood test measures two types of proteins: globulin and albumin. If protein levels are low, it can mean that you have liver or kidney disease.
- Serum protein electrophoresis. This blood test measures gamma globulins and other proteins in your blood. It can be used to diagnose a variety of conditions, including disorders of the immune system and a type of cancer called multiple myeloma.
Other names for globulin tests: Serum globulin electrophoresis, total protein
Formal Name: Total Protein Albumin to Globulin Ratio
Calculated globulin (CG)
Calculated globulin (total protein – albumin) is usually tested as part of a liver function test profile in both primary and secondary care and determines the serum globulin concentration, of which immunoglobulins are a major component. The main use hitherto of calculated globulin is to detect paraproteins when the level is high. This study investigated the potential to use low levels of calculated globulin to detect antibody deficiency. Serum samples with calculated globulin cut-off < 18 g/l based on results of a pilot study were collected from nine hospitals in Wales over a 12-month period. Anonymized request information was obtained and the samples tested for immunoglobulin levels, serum electrophoresis and, if appropriate, immunofixation.
What is it used for?
Globulin tests can be used to help diagnose a variety of conditions, including:
- Liver damage or disease
- Kidney disease
- Nutritional problems
- Autoimmune disorders
- Certain types of cancer
Why do I need a globulin test?
Your health care provider may order globulin tests as part your regular checkup or to help diagnose specific conditions. A total protein test may be included in a series of tests to check how well your liver is working. These tests, called liver function tests, may be ordered if you are at risk for liver disease or have symptoms of liver disease, which may include:
- Jaundice, a condition that causes your skin and eyes to turn yellow
- Nausea and vomiting
- Recurring fatigue
- Fluid buildup in the abdomen, feet, and legs
- Loss of appetite
A serum protein electrophoresis test measures gamma globulins and other proteins. This test may be ordered to diagnose disorders related to the immune system, including:
- Autoimmune diseases such as lupus and rheumatoid arthritis
- Multiple myeloma, a type of cancer
Purpose of the test
The purpose of a total protein test is to check the levels of proteins in the blood. Too much or too little protein can reflect conditions including liver or kidney disease, infection, inflammation, malnutrition, and cancer. In many cases, the total protein measurement and A/G ratio are included as part of broader tests, such as the liver panel or comprehensive metabolic panel, that offer further information about possible health conditions.
In addition to the total protein level, testing can determine the ratio between types of proteins known as albumin and globulins. The albumin-to-globulin ratio, or A/G ratio, can also be used to look for signs of an underlying health issue.
This testing can be utilized as part of diagnosis, screening, and/or monitoring:
- Diagnosis happens after you have symptoms and includes tests that work to determine what is causing those symptoms.
- Screening involves tests that look for health problems before they have caused any symptoms. Panel tests including total protein, for example, may be part of routine checkups for people who have a higher risk of developing liver or kidney disease with the hope of detecting problems at an earlier stage.
- Monitoring is testing that is used to follow a person’s condition over time or in response to treatment. Total protein may be measured in repeat tests at regular intervals in people who have known liver or kidney problems. It can also be part of panel tests to check liver and kidney health when taking medications that can affect these organs.
Risks and Contraindications
Globulin tests require a blood sample. A blood draw (venipuncture) is a routine procedure that can be completed at a healthcare provider’s office, clinic, or outpatient lab.
Most people don’t experience any problems during or after a blood draw. However, when a vein is punctured it’s possible the following can occur:
- Broken blood vessels under the skin (hematoma)
- Dizziness or lightheadedness
- Excessive bleeding
- Infection resulting from skin puncture
While they do not typically occur, these outcomes can be addressed immediately and generally do not have longterm medical consequences.
For healthy people, the overall risk associated with venipuncture is low. The technicians who perform blood draws take steps to lower the risk, such as using single-use needles and appropriate safety precautions.
In most cases, the benefits of the test outweigh the risk associated with having blood taken. However, there are cases where a person should not have a blood draw (contraindication). For example, if they have a skin infection (cellulitis) in the area.
What happens during a globulin test?
Globulin tests are blood tests. During a blood test, a health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
How to get tested
A total protein test is typically performed after it has been prescribed by a doctor. The blood sample is normally taken with a blood draw in a hospital, doctor’s office, or similar medical setting.
Can I take the globulin test at home?
Some at-home test kits include total protein and albumin. With these kits, you can collect a blood sample at home with a fingerstick, but the sample must be mailed to a laboratory where the total protein can be measured.
How much does globulin test cost?
The cost of a total protein test may vary based on a number of factors including where the test is taken, whether other measurements are included in the test, and whether you have any type of health insurance.
Instead of one total cost, there may be separate bills for office visits, technician fees for the blood draw, and laboratory analysis. These charges are often covered by insurance if your doctor prescribes a total protein test, but you should contact your insurance company to find out if you are responsible for a deductible or copayments.
Will I need to do anything to prepare for the test?
You don’t need any special preparations for a globulin test. If your health care provider has also ordered other blood tests, you may need to fast (not eat or drink) for several hours before the test. Your health care provider will let you know if there are any special instructions to follow.
Are there any risks to the test?
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
What do the results mean?
Low globulin levels can be a sign of liver or kidney disease. High levels may indicate infection, inflammatory disease or immune disorders. High globulin levels may also indicate certain types of cancer, such as multiple myeloma, Hodgkin’s disease, or malignant lymphoma. However, abnormal results may be due to certain medications, dehydration, or other factors. To learn what your results mean, talk to your health care provider.