Direct Antiphospholipid Antibody Screening (Anti-Cardiolipin Antibody, IgG and IgM)
This test measures antibodies in your blood that may indicate an autoimmune condition called antiphospholipid syndrome (APS). APS can increase your risk of blood clots and other complications.
["This screening helps identify potential autoimmune-related blood clotting risks."]
Key facts at a glance
- LOINC
- 51007-3
- Short code
- DAT p transf RBC Ql
- Synonyms
- DAT p transf RBC Ql
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85041
- SNOMED
- 900000000000003001
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
The test detects two types of antibodies—IgG and IgM—against cardiolipin, a protein found in cell membranes. These antibodies are linked to a higher likelihood of forming blood clots, which can affect blood flow in your body.
Why It’s Done
Your healthcare provider may order this test if you have symptoms like unexplained blood clots, recurrent miscarriages, or other signs of autoimmune disorders. It can also be part of a broader evaluation for conditions like lupus or other connective tissue diseases.
How the Test Works
A small blood sample is taken, and the lab analyzes it using an immunoassay method to detect the presence of IgG and IgM antibodies against cardiolipin. Results are reported as positive or negative for each antibody type.
What the Results Mean
Positive results suggest a higher likelihood of antiphospholipid syndrome or related autoimmune activity. However, further testing (such as lupus anticoagulant screening) may be needed to confirm a diagnosis.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is important because undiagnosed antiphospholipid syndrome can lead to serious complications like deep vein thrombosis, pulmonary embolism, or stroke. Early detection allows for management strategies, such as blood thinners, to reduce risks.
Short name
Anti-Cardiolipin Antibody Test (Screening)
Frequently asked questions
What does a positive result mean for my health?
How often should I get this test?
Can lifestyle changes help if I have a positive result?
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 17, 2026. · Read our editorial policy