Examinations
Examinations
The antiphospholipid antibody test is used to detect specific phospholipid-binding proteins that the body produces against itself as part of an autoimmune response to phospholipids. Phospholipids, which are components of the body's cells, are found in cell membranes and platelets. Essentially, these are fat molecules that play a crucial role in blood clotting, though their exact mechanism of action remains unclear. Antiphospholipid antibodies increase the risk of blood clotting disorders and contribute to the formation of clots in arteries and veins, potentially leading to strokes and heart attacks.
Clinical Significance
Antiphospholipid antibodies are also associated with an increased risk of:
- Thrombocytopenia (a decrease in blood platelet count)
- Recurrent miscarriages (particularly in the second and third trimesters)
- Preterm birth
- Late-stage toxicosis (preeclampsia/eclampsia)
The presence of these antibodies is a key component of antiphospholipid syndrome (APS), also known as Hughes-Stovin syndrome. This condition includes:
- Thrombosis
- Obstetric complications (miscarriage, abortion)
- Thrombocytopenia
APS may develop alongside other autoimmune diseases, particularly systemic lupus erythematosus (secondary APS), or it may occur independently (primary APS).
- Discontinue heparin and its analogs5 days before the test (only under a doctor’s supervision).
- Avoid smoking for 30 minutes before the test.
- To determine the causes of thrombotic microangiopathy, recurrent pregnancy loss (late-term), thrombocytopenia, and prolonged thromboplastin formation.
- If antiphospholipid syndrome is suspected (testing should be performed at least twice, with an interval of 6 weeks).
- In cases of recurrent miscarriages, along with the APTT test.
- In young patients with recurrent thrombosis.
- During thrombocytopenia.
- If symptoms of thrombotic microangiopathy appear (pain and swelling in the limbs, shortness of breath, and headaches).
Additional Uses
In rare cases, an antiphospholipid antibody test is performed to determine the cause of a false-positive syphilis result. The reagents used in syphilis testing contain phospholipids, which can lead to false-positive results in patients with antiphospholipid antibodies.
Additional Considerations
- Antiphospholipid antibodies are slightly more common in elderly individuals.
- The presence of antiphospholipid antibodies (especially in a single test) does not always indicate the development of antiphospholipid syndrome.
Recommended Additional Tests
- Lupus anticoagulant screening test (LA1)
- Anticardiolipin antibodies (IgG and IgM)
- Activated partial thromboplastin time (APTT)
- Bleeding time test
- Anti-beta-2-glycoprotein antibodies