What condition demonstrates prolonged APTT with no correction after mixing studies?

What condition demonstrates prolonged APTT with no correction after mixing studies?

• A. Lupus anticoagulant
• B. Factor IX deficiency
• C. Factor XI deficiency
• D. Hemophilia B

Answer: (A)

A prolonged activated partial thromboplastin time (APTT) that shows no correction after mixing studies indicates the presence of an inhibitor. In this scenario, a lupus anticoagulant is a type of antibody that interferes with the phospholipids necessary for the coagulation cascade, leading to prolonged APTT. When mixing studies are performed, the patient's plasma is mixed with normal plasma. If the APTT is corrected, it suggests a factor deficiency, as the normal plasma provides the needed factors for clotting. However, if there is no correction, it indicates that an inhibitor, like a lupus anticoagulant, is present. This is a critical distinction since it informs the clinical response and management of the patient, especially when considering the potential for thrombotic events versus bleeding issues associated with different coagulation disorders.

A prolonged activated partial thromboplastin time (APTT) that shows no correction after mixing studies indicates the presence of an inhibitor. In this scenario, a lupus anticoagulant is a type of antibody that interferes with the phospholipids necessary for the coagulation cascade, leading to prolonged APTT.

When mixing studies are performed, the patient's plasma is mixed with normal plasma. If the APTT is corrected, it suggests a factor deficiency, as the normal plasma provides the needed factors for clotting. However, if there is no correction, it indicates that an inhibitor, like a lupus anticoagulant, is present. This is a critical distinction since it informs the clinical response and management of the patient, especially when considering the potential for thrombotic events versus bleeding issues associated with different coagulation disorders.