Skip to content

Immunoglobulin A (IgA) in Serum or Plasma

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

This test measures the amount of Immunoglobulin A (IgA), a type of antibody in your blood. IgA helps protect your body from infections and is important for immune function.

Quick summary

["IgA levels help assess immune health and detect potential deficiencies or disorders."]

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

Key facts at a glance

LOINC
17005-0
Short code
IgA1 CSF-mCnc
Synonyms
IgA1 CSF-mCnc
Category
chemistry
Sample
csf
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82784
Specimen volume
1-2 mL
Stability
Immediate analysis required, Refrigerated: 1h
Hemolysis max
200
TAT
4–24 hours
Order
routine

What IgA Is and Its Role in Your Body

IgA is a key part of your immune system, found in blood, mucus, saliva, and other bodily fluids. It helps fight off bacteria and viruses by binding to them and marking them for destruction by other immune cells. Low or high levels can indicate underlying health conditions.

Why This Test Might Be Ordered

Doctors may order an IgA test to check for immune system issues, such as a deficiency that increases infection risk, or to diagnose conditions like IgA nephropathy (a kidney disease linked to IgA deposits) or certain autoimmune disorders.

Common Reasons for Testing

Common reasons include recurrent infections, unexplained kidney problems, or symptoms of immune-related diseases. It may also be part of a broader evaluation for conditions like celiac disease or certain inflammatory disorders.

What to Expect Before the Test

No special preparation is needed. You’ll typically have a small needle inserted into your arm or vein to draw blood. If you’re nervous, let your healthcare provider know—they can offer comfort measures.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

IgA Level

Frequently asked questions

How long does it take to get results?
Results are usually available within 1–3 business days, depending on your lab. Follow up with your doctor if you have questions about your results.
Can I eat or drink before the test?
You can eat and drink normally before the test unless instructed otherwise by your doctor.
What if my IgA level is low?
A low IgA level may suggest an immune deficiency or certain autoimmune conditions. Your doctor will discuss next steps, which could include further testing or treatment recommendations.
  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