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Cardiolipin Antibody (IgG) - High-Sensitivity

Published: August 9, 2026Updated: August 15, 2026

This test measures the presence of antibodies against cardiolipin, a phospholipid found in cell membranes. These antibodies may be linked to certain autoimmune conditions.

Quick summary

This test helps assess potential autoimmune or inflammatory conditions, including lupus or other connective tissue disorders.

Medically reviewed by WellAlly Editorial TeamLast reviewed August 15, 2026Editorial policy

Key facts at a glance

LOINC
42729-4
Short code
CARDIGA
Synonyms
Cardiolipin IgA B2GP1 dep MoM Ser
Category
chemistry
Sample
serum
Container
Serum separator tube (SST) - red-top or gold-top tube
Units
N/A
Ref low
20
Ref high
39
Critical range
— – 80 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–99 years
Method
Enzyme-linked immunosorbent assay (ELISA) detecting IgA antibodies against cardiolipin complexed with beta-2 glycoprotein 1
CPT
86147
SNOMED
12182000
Specimen volume
1.0 mL serum (minimum 0.5 mL)
Stability
Room temperature: 8 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days. Avoid repeated freeze-thaw cycles.
Hemolysis max
100
Lipemia max
100
Icterus max
50
TAT
24–72 hours
Order
routine

Why This Test Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms or a history suggestive of autoimmune diseases, such as joint pain, fatigue, or unexplained rashes. It can also be part of a broader evaluation for conditions like lupus or antiphospholipid syndrome.

What to Expect Before the Test

No special preparation is needed. You’ll provide a blood sample, typically drawn from a vein in your arm. If you’re on blood thinners, inform your provider before the test.

What the Results Mean

Positive results indicate the presence of cardiolipin antibodies, which may signal an autoimmune response. However, results alone don’t diagnose a condition—your provider will consider them alongside other factors, including symptoms and lab results.

Common Conditions Linked to Positive Results

Elevated levels of these antibodies are often associated with autoimmune disorders like systemic lupus erythematosus (SLE), antiphospholipid syndrome, or other connective tissue diseases. They may also appear in people with no symptoms.

Reference range

Negative: <20 MPL-U/mL (Multiple of the Median); Equivocal: 20-39 MPL-U/mL; Positive: ≥40 MPL-U/mL. Reference ranges expressed as multiples of the median (MoM) of a healthy reference population.N/A

Specimen: serum

No fasting required. Patient should be informed that this test should be repeated after at least 12 weeks to confirm persistent positivity, as recommended by international antiphospholipid syndrome classification criteria.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

This test plays a key role in diagnosing or monitoring autoimmune conditions where phospholipid antibodies are suspected. While not definitive, it helps guide further testing or treatment decisions. False positives can occur, so results should be interpreted with clinical context.

Short name

IgG Cardiolipin Antibody (High-Sens)

Frequently asked questions

Will this test show if I have lupus?
This test can help identify antibodies linked to lupus or related conditions, but it’s not the only test used. Lupus diagnosis often involves multiple tests, including other autoantibody panels and clinical evaluation.
What does a positive result mean for my health?
A positive result suggests a higher likelihood of an autoimmune or inflammatory process, but it doesn’t confirm a diagnosis. Your provider will discuss next steps, which may include additional testing or monitoring.
Can I stop taking medications before this test?
If you’re on blood thinners (e.g., warfarin, aspirin), inform your provider before the test. Otherwise, no special adjustments are needed unless directed by your healthcare team.
  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 15, 2026. · Read our editorial policy