A 35-year-old woman presents with epistaxis. She has a history of menorrhagia and frequent nose bleeds. She is prescribed a medication to help with this but cannot recall its name or why she takes it. She states that her father and brother also suffer with the same disorder. You have organised a set of blood tests for her.

The results are shown below:

  • Hb 12.2 g/dl (12-15 g/dl)
  • MCV 82 fl (80-100 fl)
  • Platelets 212 x 109/l (150-400 x 109/l)
  • Bleeding time 11 minutes (2-7 minutes)
  • Prothrombin time 12 seconds (10-14 seconds)
  • Thrombin time 17 seconds (15-19 seconds)
  • APTT 60 seconds (35-45 seconds)
1. What is the most likely diagnosis?
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The most likely diagnosis, in this case, is von Willebrand disease (vWD).

It arises from a deficiency in Von Willebrand factor (vWF), which causes a reduction in factor VIII levels. Ths occurs because vWF binds to factor VIII to protect it from rapid breakdown within the blood. vWF is additionally required for platelet adhesion, and a deficiency of it will also result in abnormal platelet function. It, therefore, prolongs both the APTT and the bleeding time. The platelet count and thrombin time are, however, unaffected.

Many patients with vWD are asymptomatic and are diagnosed following a coincidental check of the clotting profile. If symptomatic the most common symptoms are easy bruising, epistaxis and menorrhagia. In severe cases more severe bleeding and haemarthroses can occur.

2. What is the most common mode of inheritance of this disorder?
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Von Willebrand disease is the most common hereditary coagulation disorder occurring in approximately 1 in 100 of the population. Most cases are inherited in an autosomal dominant fashion.

3. Which medication is she most likely to have been prescribed?

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Desmopressin can be used to treat bleeding in mild cases of von Willebrand disease. This works by raising the patient’s own levels of vWF by releasing vWF that is stored in the Weibel-Palade bodies in the endothelial cells. The Weibel-Palade bodies are the storage granules of endothelial cells that form the inner lining of the blood vessels and the heart. More severe cases are treated with replacement therapy using cryoprecipitate infusions or Factor VIII concentrate. Replacement therapy is advised for patients with severe von Willebrand’s disease that are having moderate or major surgical procedures performed.

 

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