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Cardiolipin Antibody (IgG) – Serum

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

Key facts at a glance

LOINC
110787-9
Short code
CARDIOLG
Synonyms
Cardiolipin IgG Msmt Ser
Category
chemistry
Sample
serum
Container
Serum separator tube (SST, gold top) or red-top clot activator tube; alternatively, plain red-top tube without anticoagulant
Units
N/A
Ref low
0
Ref high
10
Critical range
— – 40 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
Enzyme-linked immunosorbent assay (ELISA) or chemiluminescence immunoassay (CLIA) for detection of IgG antibodies directed against cardiolipin
CPT
86147
SNOMED
445297008
Specimen volume
1.0–2.0 mL of serum (minimum 0.5 mL); pediatric minimum 0.5 mL whole blood in appropriate microtainer
Stability
Serum stable at room temperature (20–25°C) for 8 hours; refrigerated (2–8°C) for 7 days; frozen at -20°C or colder for up to 6 months. Avoid repeated freeze-thaw cycles.
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
24–72 hours
Order
routine

What Does This Test Measure?

Cardiolipin is a lipid (fat) molecule naturally present in cell membranes. When the immune system mistakenly targets these molecules, it may produce antibodies called cardiolipin antibodies. This test specifically detects IgG antibodies against cardiolipin, which can be associated with autoimmune diseases like lupus or antiphospholipid syndrome.

Why Might You Need This Test?

Your healthcare provider may order this test if you have symptoms suggestive of autoimmune disorders, such as unexplained blood clots, recurrent miscarriages, or chronic joint pain. It can also be part of a broader evaluation for conditions like lupus or other connective tissue diseases.

How Is the Test Performed?

A blood sample is drawn from a vein in your arm. The blood is processed to separate the serum (liquid part of blood without clotting factors) for testing. The test uses a specialized immunoassay to detect cardiolipin antibodies in your serum.

What Are Possible Results?

Results are qualitative (positive or negative) rather than numeric. A positive result indicates the presence of cardiolipin antibodies, which may warrant further evaluation by your healthcare provider.

Reference range

Negative: <10 GPL-U/mL; Equivocal/Borderline: 10–14 GPL-U/mL; Positive: 15–40 GPL-U/mL (low to moderate); Strongly Positive: >40 GPL-U/mL (high). Reference values may vary by laboratory and assay manufacturer.N/A

Specimen: serum

No fasting required. Patient should be well-hydrated. Inform the ordering physician of any current anticoagulant therapy, recent infections, or vaccinations, as these may transiently elevate antiphospholipid antibody titers. Repeat testing after at least 12 weeks is recommended to confirm persistent positivity per international consensus criteria.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

IgG Cardiolipin Antibody

Frequently asked questions

Why is this test important in diagnosing autoimmune conditions?
Cardiolipin antibodies are often linked to antiphospholipid syndrome (APS), a condition where the immune system mistakenly attacks blood vessels, leading to clotting problems. They may also be associated with lupus or other autoimmune diseases. While not definitive by itself, this test can help guide further testing or treatment decisions.
What does a positive result mean for my health?
A positive result suggests an increased likelihood of autoimmune activity, but it does not confirm a specific diagnosis. Your healthcare provider will consider your symptoms, medical history, and other test results to determine the next steps, which may include additional testing or monitoring.
Can lifestyle changes affect this test result?
No, this test measures antibodies in your blood and does not directly respond to lifestyle factors. However, managing underlying autoimmune symptoms through diet, exercise, and medications (if prescribed) can help overall health and may influence how your body responds to treatments.
  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