The tracing shown represents a patient with which von Willebrand disease status?

The tracing shown represents a patient with which von Willebrand disease status?

• A. Type 1 vW disease
• B. Type 2 vW disease
• C. Type 3 vW disease
• D. No vW disease

Answer: (D)

Ristocetin-induced platelet aggregation relies on von Willebrand factor to bridge platelets through the GPIb-IX-V complex. A tracing that shows normal aggregation with ristocetin means that this interaction is functioning properly and vWF is present in adequate amount and activity. That pattern argues against von Willebrand disease, where either the quantity (type 1) or the quality (type 2) of vWF is impaired, or a complete absence of vWF (type 3) would blunt or abolish ristocetin-induced aggregation. So a normal tracing fits no vWD status because the vWF-platelet interaction is intact. In contrast, types 1, 2, or 3 would produce abnormal traces: reduced or altered aggregation depending on the specific defect, and type 3 would show minimal to no aggregation even with ristocetin.

Ristocetin-induced platelet aggregation relies on von Willebrand factor to bridge platelets through the GPIb-IX-V complex. A tracing that shows normal aggregation with ristocetin means that this interaction is functioning properly and vWF is present in adequate amount and activity. That pattern argues against von Willebrand disease, where either the quantity (type 1) or the quality (type 2) of vWF is impaired, or a complete absence of vWF (type 3) would blunt or abolish ristocetin-induced aggregation. So a normal tracing fits no vWD status because the vWF-platelet interaction is intact. In contrast, types 1, 2, or 3 would produce abnormal traces: reduced or altered aggregation depending on the specific defect, and type 3 would show minimal to no aggregation even with ristocetin.