Anti-Cardiolipin Antibodies (IgG and IgM) - Serology
This blood test measures antibodies against cardiolipin, a phospholipid found in cell membranes. These antibodies may be linked to certain autoimmune conditions or blood clotting disorders.
["This test helps assess potential autoimmune or clotting-related risks."]
Key facts at a glance
- LOINC
- 109132-1
- Short code
- COXP1IGA
- Synonyms
- C burnet Ph1 IgA Msmt Ser
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top vacutainer tube
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Enzyme-linked immunosorbent assay (ELISA) or indirect immunofluorescence assay (IFA) for detection of Coxiella burnetii phase 1 IgA antibodies
- CPT
- 86638
- SNOMED
- 122460008
- Specimen volume
- 1.0 mL serum (minimum 0.5 mL)
- Stability
- Stable for 7 days at 2-8°C; for prolonged storage, freeze at -20°C or below. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 48–168 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms like unexplained joint pain, fatigue, or a history of blood clots. It could also be part of evaluating conditions such as lupus or other autoimmune diseases.
What to Expect During the Test
A small blood sample will be taken from a vein, usually in your arm. You may feel a slight pinch, but it typically doesn’t cause significant discomfort. The process usually takes a few minutes.
Sample Collection and Preparation
The blood sample is collected in a special tube and sent to a lab for analysis. The test measures both IgG and IgM antibodies against cardiolipin, which are detected using immunoassay methods.
What the Results Mean
Results are reported as positive or negative for each antibody type. Elevated levels may indicate an increased risk of autoimmune conditions or clotting disorders, but they don’t diagnose a specific condition alone.
Reference range
Negative: <1:50 or as defined by laboratory. Phase 1 IgA titers ≥1:200 are suggestive of chronic Q fever infection. Results should be interpreted in conjunction with phase 2 IgG/IgM titers and clinical findings.N/A
No fasting required. Patients should inform their healthcare provider of any recent vaccinations, antibiotic therapy, or immunosuppressive medications as these may affect antibody response.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Anti-Cardiolipin Antibodies
Frequently asked questions
What does a positive result mean?
Can this test diagnose lupus or another condition?
How often should I get this test?
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 16, 2026. · Read our editorial policy