A 13-year-old girl is brought to the emergency department by her father because of a severe nosebleed after she fell down on her face. She takes no medications and has no history of serious medical illness but has had frequent nosebleeds in the past. Physical examination shows brisk bleeding from the right nare and pooled blood in the posterior pharynx. Laboratory evaluation shows decreased von Willebrand Factor antigen levels and activity, measured via the ristocetin cofactor assay. Which of the following sets of laboratory values is most likely present in this patient?

Question

A 13-year-old girl is brought to the emergency department by her father because of a severe nosebleed after she fell down on her face. She takes no medications and has no history of serious medical illness but has had frequent nosebleeds in the past. Physical examination shows brisk bleeding from the right nare and pooled blood in the posterior pharynx.  Laboratory evaluation shows decreased von Willebrand Factor antigen levels and activity, measured via the ristocetin cofactor assay.  Which of the following sets of laboratory values is most likely present in this patient?

Quizplus · Accepted Answer

Eductional Objective: Von Willebrand disease is the most common inherited bleeding disorder and is usually transmitted in an autosomal dominant fashion.  Symptomatic patients typically present with easy bruising and mucosal bleeding.  Laboratory evaluation will show normal platelets, normal PT, and either normal or prolonged PTT due to low levels of factor VIII.

A 13-Year-Old Girl Is Brought to the Emergency Department by Her