Which disorder is consistent with normal platelet count, normal PT, and prolonged APTT?

Which disorder is consistent with normal platelet count, normal PT, and prolonged APTT?

• A. Hemophilia A
• B. Bernard-Soulier syndrome
• C. von Willebrand's disease
• D. Glanzmann's thrombasthenia

Answer: (A)

Hemophilia A is consistent with a normal platelet count, normal PT (Prothrombin Time), and prolonged APTT (Activated Partial Thromboplastin Time). This is due to the specific deficiency of factor VIII in Hemophilia A, which affects the intrinsic pathway of the coagulation cascade. Since the platelet count remains normal, it's clear that the disorder is related to a clotting factor deficiency rather than a problem with platelet production or functionality. In this condition, although the APTT is prolonged indicating an issue with intrinsic pathway factors, the PT remains normal because the extrinsic pathway, which is assessed by PT, is functioning adequately. This lack of impact on platelet count reinforces that the primary issue is the defective coagulation factor rather than a qualitative or quantitative platelet problem.

Hemophilia A is consistent with a normal platelet count, normal PT (Prothrombin Time), and prolonged APTT (Activated Partial Thromboplastin Time). This is due to the specific deficiency of factor VIII in Hemophilia A, which affects the intrinsic pathway of the coagulation cascade. Since the platelet count remains normal, it's clear that the disorder is related to a clotting factor deficiency rather than a problem with platelet production or functionality.

In this condition, although the APTT is prolonged indicating an issue with intrinsic pathway factors, the PT remains normal because the extrinsic pathway, which is assessed by PT, is functioning adequately. This lack of impact on platelet count reinforces that the primary issue is the defective coagulation factor rather than a qualitative or quantitative platelet problem.