PLATELET VON-WILLEBRAND-FACTOR AND BLEEDING IN CHRONIC-RENAL-FAILURE

Twenty patients with stable chronic renal failure were studied to inve stigate the role of von Willebrand factor (vWf) in the bleeding tenden cy seen in uremia. A subgroup of six patients (30%) with an abnormal p latelet vWf multimer pattern consisting of greatly reduced intermediat e and high molecular weight multimers was identified. More of these pa tients reported easy bruising or bleeding (p < 0.05) when compared wit h uremic patients with a normal platelet vWf pattern, and bleeding tim e also appeared to be prolonged in this group. The expected overall po sitive correlation between plasma vWf antigen level and creatinine was seen (r = 0.63, p < 0.005). The pattern of plasma vWf multimers did n ot differ significantly from normal in any of the patients studied. Th ese findings suggest that deficiency of intermediate and high molecula r weight vWf multimers in platelets may make an important contribution to the increased tendency of uremic individuals to bleed.