Description

The Anticardiolipin Antibody (IgA) test measures IgA antibodies directed against cardiolipin, a phospholipid found in cell membranes. These antibodies are part of a group known as antiphospholipid antibodies, which can interfere with normal blood clotting processes and may be associated with autoimmune disorders.

Elevated anticardiolipin antibodies may be seen in individuals with Antiphospholipid Syndrome (APS), an autoimmune condition characterized by an increased risk of blood clots, stroke, recurrent pregnancy loss, and other vascular complications. While anticardiolipin IgG and IgM antibodies are more commonly used in the diagnosis of APS, IgA testing may provide additional information in selected patients, particularly when clinical suspicion remains high despite negative IgG and IgM results.

Who Should Consider This Test?

This test may be helpful for individuals with:

  • Unexplained deep vein thrombosis (DVT) or pulmonary embolism
  • Stroke or transient ischemic attack (TIA), especially at a younger age
  • Recurrent miscarriages or pregnancy complications
  • Suspected Antiphospholipid Syndrome (APS)
  • Systemic lupus erythematosus (SLE) or other autoimmune conditions
  • A personal or family history of abnormal blood clotting

Understanding Your Results

Elevated Results

  • May indicate the presence of antiphospholipid antibodies
  • May be associated with an increased risk of blood clot formation
  • May support the diagnosis of APS when combined with clinical findings and other laboratory tests

Normal Results

  • Suggest that significant levels of anticardiolipin IgA antibodies are not present
  • Do not completely exclude APS or other clotting disorders

Because antiphospholipid antibodies can occasionally appear temporarily following infections or other illnesses, repeat testing may be recommended to confirm persistent antibody positivity when APS is suspected.

Related Testing

Anticardiolipin IgA is often ordered along with:

  • Anticardiolipin IgG and IgM
  • Beta-2 Glycoprotein I Antibodies (IgG, IgM, and IgA)
  • Lupus Anticoagulant Testing

Specimen

Blood Draw Required

Fasting Requirements

Fasting is Not Required