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Serum IgA Immunoglobulin (Total)

Published: August 9, 2026Updated: August 16, 2026

This test measures the total amount of Immunoglobulin A (IgA), a type of antibody in your blood serum.

Quick summary

["IgA helps protect your body from infections and supports immune function."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
77208-7
Short code
SP-1 IgA Ser IA-aCnc
Synonyms
SP-1 IgA Ser IA-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ia
CPT
82784
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Might Be Ordered

Your healthcare provider may order this test to check for low or high levels of IgA, which can be linked to conditions like recurrent infections, immune system disorders, or certain autoimmune diseases. It may also be used to monitor treatment responses or investigate unexplained symptoms such as frequent colds, digestive issues, or skin problems.

What to Expect Before the Test

You can prepare for this test by following your usual routine. No special preparation is typically needed, but you may be asked to fast for 8–12 hours if your test involves a blood draw from an empty stomach. Avoid smoking or consuming alcohol for at least 1 hour before the test if instructed.

What Happens During the Test

A healthcare professional will collect a small sample of blood from a vein in your arm. The process usually takes a few minutes and may cause a slight pinch or discomfort. The sample is then sent to a lab for analysis.

What the Results Mean

Results are compared to standard reference ranges for IgA levels. Low IgA levels may suggest immune deficiencies, while very high levels could indicate certain infections, inflammatory conditions, or autoimmune disorders. Your results will be discussed with your provider to determine next steps.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

IgA Serum

Frequently asked questions

What causes IgA levels to be low?
IgA levels can be low due to genetic factors, immune system disorders (such as CVID), certain medications, or chronic illnesses. Rarely, it may also be linked to autoimmune conditions or conditions affecting the gut, like celiac disease. If your levels are low, your provider may recommend further testing or treatments to support your immune function.
What are the most common symptoms of low IgA?
Symptoms of low IgA may include frequent colds, sinus infections, or ear infections, persistent digestive issues (like diarrhea or bloating), unexplained skin rashes, or recurrent throat infections. Some people with low IgA may also have a higher risk of infections in the mouth or lungs. These symptoms don’t always appear, so testing is often done even if you don’t have obvious signs.
How is IgA tested, and what if my results are abnormal?
IgA is typically measured using an immunoassay, which detects the presence and amount of IgA in your blood serum. If your results are abnormal, your provider will discuss them with you and may recommend additional tests, such as checking other antibodies or immune markers, to understand the underlying cause. They may also suggest lifestyle changes, dietary adjustments, or other treatments to support your immune health.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy