Semin Thromb Hemost 2002; 28(2): 173-190
DOI: 10.1055/s-2002-27820
Copyright © 2002 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel.: +1(212) 584-4662

Laboratory Diagnosis of Congenital von Willebrand Disease

Ulrich Budde1 , Elke Drewke1 , Kerstin Mainusch1 , Reinhard Schneppenheim2
  • 1Coagulation Laboratory, Laboratory Association Prof. Arndt and Partners, Hamburg
  • 2Department of Hematology, Children's Hospital, University Clinic, Hamburg, Germany
Further Information

Publication History

Publication Date:
03 May 2002 (online)

ABSTRACT

Von Willebrand disease (vWD) is caused by quantitative or qualitative defects, or both, of the von Willebrand factor (vWF), a multimeric high-molecular glycoprotein (GP). Typically, it affects the primary hemostatic system, which is reflected by a mucocutaneous bleeding tendency simulating a platelet function defect. The vWF promotes its function in two ways: (1) by supporting platelet adhesion to the injured vessel wall under conditions of high shear forces and (2) by its carrier function for factor VIIIc (FVIIIc) in plasma. Because of the complexity of the disease, diagnosis of vWD is one of the most challenging of any coagulation disorder. The stepwise diagnosis of vWD includes patients and family history, screening procedures (bleeding time [BT], filter tests, platelet counts, activated partial thromboplastin time [aPTT]), confirmatory tests (vWF antigen [vWF:Ag], vWF ristocetin cofactor activity [vWF:RCo], vWF collagen-binding [vWF:CB] assay, ristocetin-induced platelet aggregation [RIPA], FVIIIc) and tests for final classification (multimeric analysis, FVIII binding capacity of vWF [vWF:FVIIIB], platelet vWF). In 1999, we classified 303 patients with congenital vWD as type 1 (n = 122), type 2 (n = 171), and type 3 (n = 10). Type 2 was further subdivided into type 2A (n = 126), type 2B (n = 17), type 2M (n = 22), and type 2N (n = 6). Type 2A showed a remarkable heterogeneity, with only 27.8% (n = 36) of the ``classic'' IIA pattern. The other high-frequency patterns were type IB (25.4% n = 32) and type IIE/F/H-like structural abnormalities (28.6% n = 36). The spectrum was completed with samples from patients with types 2D, 2C, 2C Miami, smeary structures, and other rare subtypes (together 18.9% n = 23).

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