Immunoglobulin A (IgA)

The Immunoglobulin A (IgA) test contains 1 test with 1 biomarker.

Bried Description: The Immunoglobulin A (IgA) test is a laboratory test that measures the level of IgA antibodies in the blood. IgA is a type of antibody that plays a crucial role in the body's immune response, particularly in mucous membranes such as those in the respiratory and gastrointestinal tracts.

Collection Methold: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When and Why an Immunoglobulin A Test May Be Ordered?

An Immunoglobulin A test may be ordered in the following situations:

1. Evaluation of Immune System Function: The test is often performed to assess the overall function of the immune system, specifically the IgA component. It helps determine whether the immune system is producing an appropriate amount of IgA antibodies.

2. Diagnosis of Immunodeficiency Disorders: An Immunoglobulin A test can be used to identify certain immunodeficiency disorders, such as selective IgA deficiency. In this condition, individuals have very low levels of IgA in their blood, which can make them more susceptible to infections.

3. Evaluation of Autoimmune Diseases: Some autoimmune diseases, such as celiac disease, systemic lupus erythematosus (SLE), and inflammatory bowel disease, can cause abnormalities in IgA levels. Measuring IgA levels helps in the diagnosis and monitoring of these conditions.

4. Monitoring Treatment Response: For individuals with known IgA-related disorders, such as IgA nephropathy, monitoring IgA levels can help assess the effectiveness of treatment interventions and disease progression.

What an Immunoglobulin A Test Checks For

The Immunoglobulin A test checks for the level of IgA antibodies in the blood. IgA antibodies are primarily found in the mucous membranes, where they help protect against pathogens and allergens. By measuring IgA levels, the test provides information about the immune system's ability to produce these antibodies.

Other Lab Tests That May Be Ordered Alongside an Immunoglobulin A Test

When an IgA test is ordered, it's often part of a broader evaluation of the immune system or in investigating conditions like allergies, autoimmune diseases, and gastrointestinal disorders. Here are some tests commonly ordered alongside it:

1. Immunoglobulin G and Immunoglobulin M Tests:

   • Purpose: To measure the levels of other major types of immunoglobulins in the blood.
   • Why Is It Ordered: To provide a comprehensive assessment of the immune system. Abnormal levels of these immunoglobulins can indicate immune deficiencies or dysfunctions.

2. Total Protein and Albumin:

   • Purpose: To measure the total amount of protein and albumin in the blood.
   • Why Is It Ordered: To assess overall protein levels, which can help in understanding the context of IgA levels and general health status.

3. Celiac Disease Test:

   • Purpose: To screen for celiac disease, an autoimmune disorder affecting the small intestine.
   • Why Is It Ordered: Selective IgA deficiency is relatively common in individuals with celiac disease, and celiac disease can cause elevated IgA specific to tissue transglutaminase.

4. Liver Function Test:

   • Purpose: To assess liver health.
   • Why Is It Ordered: The liver is involved in protein synthesis, including immunoglobulins, so liver disorders can affect IgA levels.

5. Kidney Function Test:

   • Purpose: To evaluate kidney function.
   • Why Is It Ordered: Kidney disease can lead to alterations in protein levels, including immunoglobulins.

6. ANA and RF:

   • Purpose: To screen for autoimmune disorders.
   • Why Is It Ordered: To help diagnose conditions like lupus, rheumatoid arthritis, and other autoimmune diseases that can affect immunoglobulin levels.

7. Allergy Testing (specific IgE):

   • Purpose: To test for specific allergen sensitivities.
   • Why Is It Ordered: In the context of allergic diseases, assessing specific IgE levels can be helpful.

8. Complete Blood Count (CBC) with Differential:

   • Purpose: Provides a broad picture of overall blood health.
   • Why Is It Ordered: To assess for signs of infection, inflammation, or other hematologic abnormalities that might be related to immune system issues.

These tests, when ordered alongside an Immunoglobulin A test, provide a comprehensive view of an individual’s immune system status and can assist in diagnosing various immune-related conditions. They are important for detecting and managing immune deficiencies, autoimmune diseases, allergic responses, and gastrointestinal disorders. The specific combination of tests will depend on the individual's symptoms, medical history, and clinical presentation.

Conditions or Diseases That Would Require an Immunoglobulin A Test

An Immunoglobulin A test may be ordered for the following conditions or diseases:

1. Immunodeficiency Disorders: Individuals suspected of having immunodeficiency disorders, particularly selective IgA deficiency, may undergo an Immunoglobulin A test to confirm the diagnosis.

2. Autoimmune Diseases: Certain autoimmune diseases, such as celiac disease, SLE, and inflammatory bowel disease, can be associated with abnormalities in IgA levels. Testing IgA levels helps in the diagnosis and monitoring of these conditions.

3. Chronic Infections: In some cases, chronic infections may lead to alterations in IgA levels. The test may be ordered to assess the immune response and aid in the diagnosis of these infections.

4. Kidney Diseases: IgA nephropathy is a kidney disease characterized by the deposition of IgA antibodies in the kidneys. Monitoring IgA levels can help evaluate disease progression and response to treatment.

How Health Care Providers Use the Results of an Immunoglobulin A Test

Healthcare providers use the results of an Immunoglobulin A test in the following ways:

1. Diagnosis: Abnormal IgA levels can help diagnose certain conditions, such as selective IgA deficiency or IgA-related autoimmune diseases.

2. Monitoring: Serial measurements of IgA levels can track changes in the immune system's response to treatment or disease progression.

3. Risk Assessment: In certain clinical situations, low IgA levels may increase the risk of infections or guide the need for preventive measures, such as vaccinations or antibiotic prophylaxis.

It's important to interpret the results of an Immunoglobulin A test in conjunction with the patient's clinical presentation and other diagnostic tests to make an accurate diagnosis and guide appropriate management.

Most Common Questions About the Immunoglobulin A test:

Understanding the Immunoglobulin A (IgA) Test

What is the Immunoglobulin A (IgA) test?

The Immunoglobulin A (IgA) test is a blood test that measures the amount of IgA, one type of antibody, in your blood. Antibodies are proteins produced by the immune system to fight off bacteria, viruses, and toxins.

Why is the Immunoglobulin A (IgA) test done?

The test is used to detect IgA deficiency, an immune system condition where your body doesn't produce enough IgA antibodies. This could make you more likely to get infections. It may also be used to help diagnose conditions such as celiac disease or autoimmune diseases.

What does a high result on the Immunoglobulin A (IgA) test mean?

Elevated levels of IgA may indicate an autoimmune disease, chronic liver disease, a respiratory or gastrointestinal infection, or a myeloma (a type of cancer).

What does a low result on the Immunoglobulin A (IgA) test mean?

Low levels of IgA could indicate IgA deficiency, which makes an individual more prone to infections, especially of the mucous membranes in the respiratory and gastrointestinal tracts.

Interpreting Immunoglobulin A (IgA) Test Results

How accurate is the Immunoglobulin A (IgA) test?

The Immunoglobulin A (IgA) test is considered to be accurate and reliable when performed in a certified laboratory by experienced technicians.

Can the Immunoglobulin A (IgA) test diagnose specific diseases?

The Immunoglobulin A (IgA) test itself cannot diagnose a specific disease, but it can provide important information that, when combined with other tests and clinical findings, can assist in diagnosing certain conditions, such as celiac disease or an IgA deficiency.

Can medication or other factors affect the results of the Immunoglobulin A (IgA) test?

Yes, certain medications can affect the level of immunoglobulins, including corticosteroids and chemotherapy drugs. Chronic alcoholism can also result in lower IgA levels.

Immunoglobulin A (IgA) Test and Specific Conditions

How is the Immunoglobulin A (IgA) test used in the diagnosis of celiac disease?

People with celiac disease often have elevated levels of certain types of IgA antibodies, specifically anti-tissue transglutaminase antibodies (tTGA) and endomysial antibodies (EMA). These specific antibodies are often tested for when celiac disease is suspected.

What conditions can cause high Immunoglobulin A (IgA) levels?

Elevated IgA levels can occur due to chronic liver disease, systemic lupus erythematosus, rheumatoid arthritis, respiratory or gastrointestinal infections, and certain types of cancer, such as multiple myeloma.

Can the Immunoglobulin A (IgA) test be used to diagnose an autoimmune disease?

The test can suggest the presence of an autoimmune condition if IgA levels are significantly elevated, but it can't diagnose a specific autoimmune disease. More specialized tests are typically necessary for a definitive diagnosis.

General Questions About the Test

What are the normal reference ranges for the Immunoglobulin A (IgA) test?

The normal range of IgA is usually between 70 and 400 mg/dL, but this can vary depending on the lab that analyzes the test. Always consult with your healthcare provider about your specific results.

Can a person with IgA deficiency lead a normal life?

Yes, many people with IgA deficiency lead normal lives. While they may be more susceptible to infections, these can typically be treated with antibiotics. In some cases, additional immunizations may be recommended.

Understanding Immunoglobulins and the Immune System

What is the role of Immunoglobulin A (IgA) in the immune system?

IgA plays a crucial role in the immune function of mucous membranes. It helps to prevent infections in the respiratory and gastrointestinal tracts and other body areas that produce and secrete mucus.

What is the difference between Immunoglobulin A (IgA) and other immunoglobulins?

Immunoglobulins, or antibodies, are proteins made by the immune system to fight antigens such as bacteria, viruses, and toxins. There are five main types: IgA, IgD, IgE, IgG, and IgM. Each has a different role and location in the body. IgA, for instance, is mainly found in areas with mucous membranes like the nose, breathing passages, digestive tract, ears, eyes, and vagina.

Can a person be deficient in Immunoglobulin A (IgA) and not other immunoglobulins?

Yes, it's possible for a person to be deficient in IgA and not other immunoglobulins. This condition is known as selective IgA deficiency.

Can I still be immune to certain diseases if I have low Immunoglobulin A (IgA)?

Yes, other types of immunoglobulins (IgG, IgM, etc.) still provide immune defense against many types of infections, even if IgA is low or absent.

What happens if I have too much Immunoglobulin A (IgA) in my body?

Having too much IgA can lead to certain health problems, including kidney disease (IgA nephropathy), in which IgA deposits in the kidneys cause inflammation.

Additional Questions

What is the link between the Immunoglobulin A (IgA) test and allergies?

IgA is not typically involved in allergic reactions. Those are usually related to IgE, another type of immunoglobulin.

Can the Immunoglobulin A (IgA) test determine if I am immune to a specific disease?

The IgA test measures total IgA in the blood, not specific to a certain antigen, so it cannot determine immunity to a specific disease. There are other specific antibody tests for that purpose.

Can the Immunoglobulin A (IgA) test predict the onset of certain diseases?

The IgA test isn't typically used to predict disease onset. However, low or high levels of IgA could suggest a higher risk for certain conditions, such as infections or autoimmune diseases.

Can changes in Immunoglobulin A (IgA) levels be reversed?

In some cases, changes in IgA levels can be reversed, especially if they're due to a treatable underlying condition. In other cases, like genetic IgA deficiency, the changes may be permanent.

Can the Immunoglobulin A (IgA) test determine if I have a genetic disorder?

While certain genetic disorders can affect IgA levels, the test alone cannot diagnose a genetic disorder.

Why might a person with normal Immunoglobulin A (IgA) levels still get frequent infections?

The immune system is complex and involves many different components, not just IgA. Therefore, a person could have normal IgA levels but still have a different issue with their immune system that makes them more susceptible to infections.

Can the Immunoglobulin A (IgA) test be used to monitor response to treatments for certain conditions?

In some cases, physicians might use IgA levels to monitor response to treatments, particularly in diseases where IgA levels are known to be affected. However, it's just one piece of the overall clinical picture.

How often should the Immunoglobulin A (IgA) test be done?

The frequency of the test will depend on individual health conditions and the doctor's assessment. For some, it might be a one-time test. For others with certain health conditions, it might be part of regular monitoring.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.