Lupus Anticoagulant

The lupus anticoagulant test detects specific antibodies in the plasma that are associated with various health issues, including thrombosis and pregnancy complications. At IntroLab in Belgrade, we offer this test to help diagnose and manage these conditions.

What is lupus anticoagulant?

Lupus anticoagulant (LA) is a specific antibody that can be found in plasma. These antibodies are part of a broader group called antiphospholipid antibodies (aPL), which target phospholipids, essential components of cell membranes. These antibodies were originally identified in patients with systemic lupus erythematosus, which is why they are named lupus anticoagulant. However, it is now understood that these antibodies can be present in a variety of conditions, including those related to thrombosis, adverse pregnancy outcomes, and autoimmune disorders. Although lupus anticoagulant can prolong blood clotting time in laboratory tests, suggesting a tendency to bleed, in patients with antiphospholipid syndrome (APS), it often leads to thrombosis. This phenomenon is known as the lupus anticoagulant paradox.

Why is measuring this parameter important?

Testing for lupus anticoagulant is essential in various medical situations. In patients with thrombocytopenia, a condition characterized by a reduced platelet count, testing for LA can be crucial in determining the most effective therapy. Additionally, for patients at a higher risk of thrombosis, testing for LA can aid in thrombosis prevention through the use of anticoagulants. This test can detect the presence of antibodies that may cause thrombosis, enabling early intervention and reducing the risk of complications.

When is this test needed?

The lupus anticoagulant test is typically recommended for individuals who exhibit symptoms or have a medical condition that may suggest a blood clotting disorder. Situations where this test may be needed include:

• Unexpected blood clots
• Recurrent miscarriages
• Prolonged bleeding times
• Unexplained abnormalities in other blood coagulation test results

How are the results interpreted?

Test results can be classified as “positive,” “negative,” or “borderline.” A positive result may suggest the presence of antibodies and a potential risk of developing blood clots. However, it is important to emphasize that a positive result does not establish a definitive diagnosis. Further tests and medical evaluations are required to confirm the diagnosis.

The importance of disclosing medications before testing

The accuracy of diagnostic tests can be significantly influenced by the use of certain medications. Medications such as oral contraceptives, estrogens, antibiotics, antipsychotics, and antidepressants can potentially lead to false-positive results. This could result in incorrect diagnoses and inappropriate treatments. Therefore, it is essential for patients to inform their doctors about all medications they are currently taking before undergoing testing. Providing this information allows doctors to accurately interpret the test results and make informed decisions about further treatment.

Details and types of lupus anticoagulant testing

Lupus anticoagulant testing can be conducted as part of a comprehensive blood coagulation evaluation, which may include other tests, such as those for antiphospholipid antibodies. In some cases, it may be necessary to repeat the test after 12 weeks to confirm or rule out a diagnosis, as lupus anticoagulant levels can fluctuate over time.