Cardiolipin Antibody (IgA) - Serum
This test measures the presence of antibodies against cardiolipin, a phospholipid found in cell membranes, specifically targeting IgA antibodies. It may be used to help evaluate certain autoimmune conditions.
["This test helps assess potential autoimmune responses linked to phospholipid-related disorders."]
Key facts at a glance
- LOINC
- 5076-5
- Short code
- CARDIOLIP
- Synonyms
- Cardiolipin IgA Ser IA-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum tube or serum separator tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 10
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Immunoassay (Enzyme-linked immunosorbent assay, ELISA)
- CPT
- 86147
- SNOMED
- 115698000
- Specimen volume
- 1-2 mL of 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
What Is Cardiolipin Antibody Testing For?
Cardiolipin antibodies are sometimes associated with autoimmune disorders that affect blood clotting, such as antiphospholipid syndrome (APS). This test helps identify elevated levels of IgA antibodies against cardiolipin, which may indicate an immune system response that could influence blood clotting or other autoimmune processes. It is not a standalone diagnostic test but may be part of a broader evaluation when symptoms like unexplained clots, recurrent miscarriages, or other autoimmune concerns are present.
How Is This Test Performed?
A blood sample is drawn from a vein in your arm. The sample is sent to a lab where it is processed to separate serum (the liquid part after clotting). The test uses an immunoassay method to detect IgA antibodies against cardiolipin. Results are reported as either positive or negative, or sometimes with a semi-quantitative indication of antibody presence.
Why Might You Need This Test?
Your healthcare provider may recommend this test if you have symptoms or risk factors for conditions like antiphospholipid syndrome (APS), such as unexplained blood clots, recurrent pregnancy loss, or autoimmune-related symptoms. It may also be part of a screening or monitoring plan for other suspected autoimmune disorders.
What Do Results Mean?
Positive results indicate the presence of IgA antibodies against cardiolipin, which may suggest an autoimmune response. However, a single positive test does not confirm a diagnosis of APS or another condition. Results are often interpreted in the context of clinical symptoms, other test results, and medical history.
Reference range
Negative: <10 APL U/mL; Equivocal: 10-15 APL U/mL; Positive: >15 APL U/mL. Reference ranges may vary by laboratory and assay manufacturer.N/A
No fasting required. No special patient preparation is necessary prior to specimen collection. Patients should be informed that anticoagulant therapy (heparin) may interfere with some assay methods.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated cardiolipin IgA antibodies can be associated with antiphospholipid syndrome, a condition that increases the risk of blood clots and other complications. While not definitive on its own, these antibodies may prompt further evaluation for autoimmune disorders or conditions affecting blood clotting. Always discuss results with your healthcare provider to understand their relevance to your specific situation.
Short name
IgA Cardiolipin Antibody
Frequently asked questions
What does a positive result mean?
Can this test be done at home?
How often should this test be repeated?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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