Platelet VWF levels are significantly reduced in patients with low VWF. Following platelet lysis, platelet VWF:Ag (A) and platelet VWF:CB levels (B) were determined in 54 patients with low VWF levels. (A) Platelet VWF:Ag was significantly reduced in LoVIC patients (n = 54, triangles) compared with controls (n = 22, circles) (mean values 0.16 vs 0.21 IU/109 platelets; *P < .05). (B) Platelet VWF:CB levels were also significantly reduced in LoVIC patients (triangles) compared with controls (circles) (mean values 0.19 vs 0.34 IU/109 platelets; P < .0001). (C) On the basis of platelet VWF:Ag and platelet VWF:CB levels, patients with low VWF levels were subdivided into 3 distinct groups of “platelet-low” (green box), “platelet-normal” (red box), and “platelet-discordant” (blue box). LoVIC patients are indicated as filled circles and healthy controls as open circles.
