Which condition would most likely present with a prolonged bleeding time and decreased platelet aggregation?

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Multiple Choice

Which condition would most likely present with a prolonged bleeding time and decreased platelet aggregation?

Prolonged bleeding time points to a defect in primary hemostasis, where platelets fail to form a proper plug at the vessel wall. Von Willebrand disease involves a deficiency or dysfunction of von Willebrand factor, the protein that allows platelets to adhere to exposed collagen and to each other via the platelet receptor GPIb. Without sufficient functional vWF, platelets don’t stick well, so bleeding lasts longer and the aggregation response—especially in tests that depend on vWF, like ristocetin-induced aggregation—is reduced. This combination of prolonged bleeding time and impaired platelet aggregation is characteristic of von Willebrand disease. The other options don’t fit as well: Factor X deficiency affects the coagulation cascade and typically alters clotting times (PT/aPTT) rather than primarily prolonging bleeding time or impairing platelet aggregation. Protein C deficiency is a prothrombotic disorder rather than a bleeding one. Aspirin ingestion can prolong bleeding time by impairing platelet function, but it is an acquired condition and does not specifically reproduce the ristocetin-dependent defect seen with vWD.

Prolonged bleeding time points to a defect in primary hemostasis, where platelets fail to form a proper plug at the vessel wall. Von Willebrand disease involves a deficiency or dysfunction of von Willebrand factor, the protein that allows platelets to adhere to exposed collagen and to each other via the platelet receptor GPIb. Without sufficient functional vWF, platelets don’t stick well, so bleeding lasts longer and the aggregation response—especially in tests that depend on vWF, like ristocetin-induced aggregation—is reduced. This combination of prolonged bleeding time and impaired platelet aggregation is characteristic of von Willebrand disease.

The other options don’t fit as well: Factor X deficiency affects the coagulation cascade and typically alters clotting times (PT/aPTT) rather than primarily prolonging bleeding time or impairing platelet aggregation. Protein C deficiency is a prothrombotic disorder rather than a bleeding one. Aspirin ingestion can prolong bleeding time by impairing platelet function, but it is an acquired condition and does not specifically reproduce the ristocetin-dependent defect seen with vWD.

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