11. Summary

Summary

• Clinical history and laboratory data consistent with von Willebrand disease, type II (lack of larger multimers)
  
• No family history
  • 2 of 5 children tested negative for vWD
    
• No bleeding history until age 72

Acquired vWD

• First described in 1970's
  
• Estimated prevalence 0.04 - 0.13%, fewer than 300 cases reported
  
• Usually encountered in adults with no personal or family bleeding history
  
• Laboratory work-up most consistent with Type II vWD

Acquired vWD: Pathophysiology

An antibody to vWF is often present but, unlike other inhibitors,
the Ab does NOT bind a functional site to prevent action; instead,
the Ab increases clearance of HMWM (fig B) by RES, causing depletion
of HMWM (fig C); mixing with normal plasma corrects ristocetin activity