What is the initial screening method for lupus anticoagulant testing?

The initial screening method for lupus anticoagulant testing is the activated partial thromboplastin time (aPTT). This test measures the time it takes for blood to clot and is sensitive to abnormalities in the coagulation pathways that are often affected by lupus anticoagulant. When lupus anticoagulant is present, it can prolong the aPTT, making it an effective initial screening tool.

In diagnosing lupus anticoagulant, the aPTT serves as the first step because it reflects the activity of several clotting factors that lupus anticoagulant can interfere with. If the aPTT is prolonged, further confirmatory testing is typically undertaken to identify the presence of lupus anticoagulant specifically.

Other tests, like prothrombin time, complete blood count, and thrombin time, do not specifically assess the pathways affected by lupus anticoagulant and are not used as initial screening methods. Prothrombin time primarily checks the extrinsic pathway and is less informative in this context, while the complete blood count is unrelated to coagulation pathways, and thrombin time assesses the final stage of the coagulation cascade but is not designed to detect the presence of lupus anticoagulant. Therefore, the aPTT stands out as the appropriate and effective