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Type IIB von Willebrand disease: a paradox explains how von Willebrand factor works

Z M Ruggeri1

  • 1Roon Center for Arteriosclerosis and Thrombosis, Division of Experimental Hemostasis and Thrombosis, Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA. ruggeri@scripps.edu

Journal of Thrombosis and Haemostasis : JTH
|January 14, 2004
PubMed

Type IIB is a variant form of von Willebrand disease in which a structural abnormality of von Willebrand factor (VWF) causes enhanced binding to the platelet glycoprotein Ib receptor. As a consequence of this functional alteration, there is a decrease in the concentration of the largest VWF multimers in plasma, and the platelet count may be episodically decreased as a consequence of microaggregation. The net result is an apparent paradox, since the presence of a hyperfunctional adhesive molecule in blood causes a bleeding tendency. Here I recall how my colleagues and I managed to understand what goes on in these patients.

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