Von Willebrand disease

Revision as of 12:34, 10 June 2015 by Rossdonaldson1 (talk | contribs) (References)

Background

  • Most common inherited bleeding disorder
  • vWF has two roles:
    • 1. Acts as cofactor for platelet adhesion
    • 2. Acts as carrier protein for factor VIII extending its half life
  • vWD results from quantitative or qualitative dysfunction of Von Willebrand factor

Clinical Features

  • Skin and mucosal bleeding
    • Epistaxis, gingival bleeding, menorrhagia
  • Hemarthrosis is unusual

Differential Diagnosis

Diagnosis

  • Bleeding time: prolonged
  • PT: normal
  • PTT: normal-mildly prolonged
  • vWF activity level: low

Treatment

  • Avoid ASA, NSAIDs, heparin
  • Intermediate purity factor VIII
    • Goal to increase VWF activity by 50-100%
    • Initial infusion of 20-40 IU/Kg
    • High replacement doses may be indicated in more severe disease
  • Platelet transfusion
    • consider if replacement therapy instituted and persistent bleeding
  • Desmopressin
    • Induces release of vWF from endothelial storage sites
    • 0.3mcg/kg IV (max 20mcg) over 30min
  • Aminocaproic acid
  • Recombinant Factor VIIa
    • Consider in type 3 VWD patients who have developed antibodies to VWF replacement
    • Increased risk of thrombosis, especially in patients with coronary artery disease

See Also

References

  • Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 7e (2010), Chapter 230. Hemophilias and Von Willebrand Disease