Screening tests for the evaluation of VWD include the platelet count, APTT, PT, bleeding time, and/or PFA-100. Which of the following results would be evident in most cases of VWD?
A) Low platelet count
B) Decreased ristocetin platelet aggregation
C) Normal ristocetin platelet aggregation
D) Normal Ag assay

Question

Quizplus · Accepted Answer

Decreased ristocetin platelet aggregation is the most common abnormal finding in VWD, as VWF plays a crucial role in platelet adhesion and aggregation. The other tests listed may be abnormal in some cases of VWD, but not in all cases. Low platelet counts may be seen in severe cases of VWD, but not necessarily in all cases. A normal Ag assay result would not be indicative of VWD.

Screening Tests for the Evaluation of VWD Include the Platelet