Immunoglobulin A Test - IgA

Recurrent infections, Chronic diarrhoea, IgA Nephropathy, HIV/AIDS.

The immunoglobulin test checks the problem with the immune system. Sometimes our body makes too many or too few immunoglobulins due to different conditions. Few immunoglobulins in our blood cause infections. While too many leads to allergies or an overactive immune system.

Immunoglobulin (Ig) is a protein that works as an antibody. Plasma cells and lymphocytes are responsible for their production. Immunoglobulins play an important role in the immune system of the body. They help in destroying foreign substances like bacteria, viruses, etc. Immunoglobulins can live either on the edges of the cells or move freely in the blood. Circulating immunoglobulins are antibodies.

There are five Immunoglobulin types. They are IgA, IgD, IgE, IgG and IgM. Each Isotope has different properties and the ability to fight with specific antigens. IgA is found in the gut, saliva, tears, breast milk, respiratory tract, etc. mucosal area and helps in the prevention of pathogen colonies. IgA makes up 15% of the total antibodies.

Your consulting physician may prescribe an IgA test to diagnose issues with the immune system. IgA tests are also done for the diagnosis of recurrent infections, especially of the lungs, stomach, sinuses, intestines or chronic diarrhoea.

IgA tests are also prescribed to people suffering from HIV/AIDS or multiple myeloma. IgA test results help to identify the autoimmune conditions in which the body makes antibodies against healthy tissues mistakenly, such as arthritis, lupus and celiac disease. Zero or low levels of IgA puts the patient at higher risk for autoimmune conditions, infections, allergies and asthma.

IgA Nephropathy (IgAN) is another such condition in which IgA deposits in the kidney, causing end-stage renal failure.

The prevalence and outcomes of IgAN are highly variable when compared between different parts of the world. IgAN is a serious problem in India owing to its higher prevalence in Asia, especially in India. Few studies show the prevalence of IgA nephropathy in the southern part of India. When compared with the data from the rest of the world, the results of patients from India are alarming and saddening, almost 50%, which is a burden in itself.

Other names of IgA test

• Gamma-Globulins, Quantitative
• IgA single test
• Immune Competence
• Immunoglobulin A (IgA), Serum
• Total Immunoglobulins
•  Immunoglobulin A
•  IgA
• Immunoglobulins, Quantitative

What does the IgA test detect and who is this prescribed for?

The body produces antibodies to fight harmful, disease-causing substances, bacteria, viruses etc. IgA test detects the number of antibodies called immunoglobulins in your body.

Some conditions or family history cause the body to make too many or too few immunoglobulins. Having deficient immunoglobulins in the blood gives you a greater chance of getting infections. Also gives the idea that you have allergies or an overactive immune system.

The Immunoglobulin Test is prescribed by a doctor if the person has infections of the lungs, sinuses, intestines or stomach. The IgA test is also prescribed in the following conditions:

• Persistent Diarrhoea
• Fevers having no relatable causes
• Allergies
• Unintended weight loss
• Skin rashes
• Illness after travelling

Some diseases for which an IgA Test can be prescribed are:

• HIV/AIDS or multiple myeloma
• IgA nephropathy
• Arthritis
• Lupus
• Celiac disease

The IgA test is applicable to people of any gender or age.

IgA antibodies shield body surfaces that are in contact with foreign substances. These antibodies are found in blood, saliva and tears. IgA antibodies constitute around 10-15% of the total antibodies.

Bodies of some people do not produce IgA antibodies due to some reasons. They have a higher chance of developing a potentially life-threatening reaction to a procedure like a blood transfusion.

The range for the Immunoglobulin A test varies according to the age of the person. Given below is a table for reference:

The main component of the Immunoglobulin A test is the antibodies. If the result of the Immunoglobulin A test shows a high level of IgA antibodies, then it could be an indication of the following conditions:

• Allergies
• Autoimmune disorders like rheumatoid disorder, lupus or celiac disease
• Inflammatory Bowel Disease
• Chronic infections
• Liver-related Disease
• Cancer such as lymphoma or leukaemia

Low levels of IgA interpret the following conditions:

• Diabetes Complications
• Kidney Disease or Kidney Failure
• HIV/AIDS

High or low levels of Immunoglobulins is not the diagnosis of any of the above-mentioned diseases and a doctor should be consulted for better IgA test results interpretation.

IgA test is performed on blood samples. The blood sample is collected from a vein of the arm.

No special requirement is needed for an IgA test.

Test Preparation for IgA Test

No special preparations are needed for an immunoglobulin blood test. A phlebotomist collects the blood from a vein in your arm. A little pricking sensation is felt. It hardly takes 5-10 minutes.

Risks

The risks involved with a blood test are very low. At the point of needle insertion, you will feel slight pain and bruising, but these symptoms go away quickly.

What might affect your test results?

There are certain reasons which might make it difficult for you to take the IgA test or affect the results of the IgA test. They include:

• Certain medications for birth control, heart failure, seizures and rheumatoid arthritis. Always keep your doctor in the loop of the medicines you are on.
• Receiving a blood transfusion in the past six months.    
• Using alcohol or illegal drugs.    
• Getting vaccinations, especially with repeat doses, in the past six months.
• Radiation and chemotherapy sessions for cancer patients.
• Having had a radioactive scan in the past three days.

IgA test inclusions: What parameters does it include?

Some Immunoglobulin A test parameters are:

• Test the levels of IgA in the blood
• Monitor excess or deficiency of IgA
• Test Antibodies

These are the only parameters covered under this test. An IgA test checks the level of Immunoglobulins or antibodies in the blood. Antibodies are nothing but proteins produced by your immune system to ward off harmful substances like bacteria and viruses. The result of the IgA test is not expressed as positive or negative. If the value is on the higher side or lower side, it is an indicator of a disorder with the immune system.

How frequently should you take this test?

The doctor recommends Immunoglobulin A test when a person has signs of chronic inflammation or recurrent infections. When healthcare practitioners suspect excess or abnormal immunoglobulin production, they recommend IgA tests. A doctor orders this test intermittently to observe the course of a person's condition.