Acquired coagulation inhibitors have become a popular area of research because they cause severe bleeding tendency in many patients. The use of acquired coagulation inhibitors requires rapid and precise diagnosis. Some acquired coagulation inhibitors show prolongation in the activated partial thromboplastin time (APTT) and/or prothrombin time (PT). To diagnose these disorders, mixing test is very useful. However, lupus anticoagulant related disorders, such as lupus anticoagulant hypoprothrombinemia syndrome (LAHPS), are difficult to diagnose because they are sometimes associated with a reduction in factor VIII and are thus difficult to distinguish from acquired hemophilia. Acquired factor XIII deficiency and acquired von Willebrand syndrome (AvWS) are easily overlooked because they show normal value in several patients with APTT and PT. Here I describe the diagnostic method for these disorders. In particular, five acquired coagulation inhibitors that appear to be clinically significant are studied.
Keywords: APTT mixing test; Acquired coagulation inhibitors; Acquired von Willebrand disease; Lupus anticoagulant.