Von Willebrand disease

00:00 / 00:00



Von Willebrand disease

Hematological system

Coagulation disorders


Vitamin K deficiency

Leukemoid reaction

Leukemoid reaction


Von Willebrand disease

USMLE® Step 1 questions

0 / 1 complete

High Yield Notes

6 pages


USMLE® Step 1 style questions USMLE

of complete

A 4-year-old girl presents to the emergency department with abdominal pain, diarrhea, and fatigue. The patient was in her usual state of health until yesterday afternoon, when her family returned home from a barbeque. The patient is otherwise healthy and takes no medications aside from amoxicillin for a recent episode of otitis media. According to her parents, the patient’s urine has looked “darker” than usual. Temperature is 39.0°C (102.2°F), pulse is 115/min, respirations are 22/min, and blood pressure is 100/70 mmHg. Physical examination demonstrates a pale appearing girl with diffuse abdominal tenderness to palpation, delayed capillary refill, and gingival bleeding. Multiple tiny, brownish-purple, blanchable spots are noted under the skin. Which of the following laboratory findings are most consistent with this patient’s disease process?  


Von Willebrand disease is a bleeding disorder caused by a deficiency in the quantity, or the quality of von Willebrand factor, a plasma glycoprotein that plays a key role in forming blood clots needed to stop bleeding. The disease was named after Erik Adolf Von Willebrand, a Finnish physician who first described it in 1924.

Von Willebrand factor is synthesized and stored in the endothelial cells and megakaryocytes. Its synthesis is regulated by the von Willebrand factor gene located on the short arm of chromosome 12.

Alright, when there is a bleeding injury to a blood vessel, histamine and thrombin stimulate the local endothelial cells and megakaryocytes to release the von Willebrand factor into the bloodstream.

After its release, it attaches to the exposed collagen fibers located in the wall of an injured blood vessel, where it serves as a glue-like substance that sticks to platelet receptors known as glycoprotein 1b or simply Gp1b.

Within the bloodstream, more of von Willebrand factor start to bind more platelets together into kind of a mass, over which fibrin fibers deposit forming a clot needed to plug the injured vessel, and thus stop bleeding.

In addition to binding platelets together, von Willebrand factor also binds and carries factor VIII. Factor VIII plays a major role in the blood clot formation process, and to work well, it is supposed to be bound to the von Willebrand factor, because in this case it is protected from early degradation by protein C, and S, which would remove it from the circulation before it does its job.

Now in von Willebrand disease there isn’t enough working von Willebrand factor to help with platelet adhesion and to bind and carry factor VIII, both of which makes it really hard to stop bleeding.

The majority of von Willebrand disease cases are inherited, but it can also be acquired. In the inherited form, there is a mutation in the Von Willebrand gene, and the gene gets passed from parents to children. Inherited von Willebrand disease is classified into three main types - type I, II, and III.

Von Willebrand disease type I is the most common, making up 75 percent of all cases. It is autosomal dominant, meaning that a mutation in only one allele results in insufficient, or even defective production of von Willebrand factor.


Von Willebrand disease is a bleeding disorder caused by a deficiency in the quantity or quality of von Willebrand factor, a plasma glycoprotein that plays a key role in forming blood clots. Symptoms depend on the type of the disease and range from mild to severe. People with acquired von Willebrand disease present with new onset of bleeding in the context of other pathologic conditions or medication use. For treatment, people who present with minor bleeding are treated with desmopressin analogs, while those with severe bleeding receive exogenous von Willebrand factor and factor VIII concentrates.


Copyright © 2023 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Cookies are used by this site.

USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.