Platform
Company
Immunology & Autoimmune
Review status
Currently under review
Pending specialist review and validation.
The anticardiolipin IgG test measures IgG autoantibodies that target cardiolipin, a phospholipid that helps regulate blood clotting on cell and platelet surfaces. It is performed on a blood sample using an immunoassay. Detecting these antibodies helps assess whether your immune system is reacting against components involved in clotting.
This test is commonly ordered as part of an antiphospholipid antibody evaluation together with anticardiolipin IgM, anti–beta-2 glycoprotein I, and lupus anticoagulant. Antiphospholipid antibodies can appear temporarily with infections or persist in autoimmune conditions. Your result provides context about the presence of this specific antibody type.
Anticardiolipin IgG is clinically linked to a higher tendency for blood clots and certain pregnancy complications. Your clinician may order it if you have an unexplained clot, stroke at a younger age, specific pregnancy losses, or features of autoimmune disease. Among anticardiolipin antibody types, the IgG class is generally considered the most informative for risk assessment.
Identifying these antibodies can guide care, including decisions about blood thinners, safe contraceptive options, surgery planning, and pregnancy management. A negative result helps rule out this antibody as a contributor to symptoms, while a positive result may prompt confirmation testing and a broader evaluation for antiphospholipid syndrome.
Your report indicates whether anticardiolipin IgG was detected and the level according to your laboratory’s method. Low-level or single-time positivity can occur during infections or other short-lived immune responses and may not indicate a lasting problem.
If positive, your clinician may repeat the test after several months and pair it with related antibody tests, since a sustained pattern provides stronger clinical evidence. A single positive result does not diagnose antiphospholipid syndrome, and many people with these antibodies never develop a clot or pregnancy complication. Discuss your result with your clinician in the context of symptoms, medical history, and medications to decide on monitoring and treatment.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Viral or bacterial infections and other inflammatory illnesses can trigger temporary anticardiolipin antibody positivity. Retesting after you have fully recovered helps determine whether the antibody is persistent.
Some drugs, such as certain antibiotics and antiepileptics, have been associated with transient positive results. Blood thinners do not usually affect this immunoassay but can influence related clot-based tests that are often ordered alongside it.
Hemolyzed, lipemic, or poorly stored samples can interfere with immunoassay performance. Proper collection, timely processing, and avoiding testing during acute illness can improve result reliability.
Autoimmune diseases like systemic lupus erythematosus are associated with persistent antiphospholipid antibodies. Results should be interpreted together with clinical history and additional antibody testing.
Physiologic changes in pregnancy and the postpartum period can influence antiphospholipid antibody testing and risk assessment. If positive, confirmation on a later sample and coordinated obstetric care are important.
References