Bleeding Disorders

Question 1

Haemophilia A is a deficiency of which clotting factor?

Answer 1

Factor VIII

Question 2

Haemophilia B is a deficiency of which clotting factor?

Answer 2

Factor IX

Question 3

Haemophilia results in excess bleeding because it makes primary haemostasis less effective. T/F?

Answer 3

False - Haemophilia results in excess bleeding because it makes secondary haemostasis less effective

Question 4

What is the mode of inheritance for haemophilia A and B?

Answer 4

X-linked recessive

Question 5

Which sex is primarily affected by haemophilia?

Answer 5

Males

It is an x-linked recessive condition

Question 6

A family history of haemophilia is always present in patients with. haemophilia. T/F?

Answer 6

False - up to 30% of new cases are. the result of sporadic mutations

Question 7

The likelihood of bleeding can be roughly predicted from the level of Factor VIII present in haemophilia A. How is severe haemophilia A classified?

Answer 7

Factor VIII level <2 units /dL

Frequent spontaneous bleeds into joints and muscles

Question 8

The likelihood of bleeding can be roughly predicted from the level of Factor VIII present in haemophilia A. How is moderate haemophilia A classified?

Answer 8

Factor VIII level 2-5 units /dL

Some spontaneous bleeds. Bleeding after minor trauma

Question 9

The likelihood of bleeding can be roughly predicted from the level of Factor VIII present in haemophilia A. How is mild haemophilia A classified?

Answer 9

Factor VIII level 5-45 units /dL

Excessive bleeding after significant trauma or surgery

Question 10

At what stage in development does haemophilia A become apparent?

Answer 10

When the child begins to crawl

Question 11

Haemarthrosis is the most common problem in haemophilia A. Which joints are most commonly affected by this?

Answer 11

Elbows and knees

Question 12

What are the clinical features of haemophilia A?

Answer 12

Haemarthrosis
Easy bruising (ecchymosis)
Haematomas
Prolonged bleeding after cuts
GI bleeding
Haematuria
Severe nosebleeds (epitaxes)

Question 13

What result would you expect to see on PT and APTT for a patient with haemophilia?

Answer 13

PT - normal

APTT - prolonged

Question 14

Besides APTT, what test can be used to confirm haemophilia?

Answer 14

Clotting factor assay

Question 15

Describe the management of haemophilia A?

Answer 15

Injections of Factor VIII concentrate which can often be self-administered during bleeds
Desmopressin is useful in mild haemophilia A

Question 16

Why is desmopressin useful for the treatment of patients with mild haemophilia A?

Answer 16

Desmopressin stimulates vWF release from endothelial cells which promotes the stabilisation of residual Factor VIII

Question 17

What is the most common inherited bleeding disorder?

Answer 17

Von Willebrand disease

Question 18

What are the two key functions of Von Willebrand factor?

Answer 18

1) Promotion of platelet adhesion to damaged endothelium and other platelets
2) Transport and stabilisation of Factor VIII

Question 19

Type one Von Willebrand disease is most common. What is the mode of inheritance for this condition?

Answer 19

Autosomal dominant

Question 20

Describe the clinical features of severe Von Willebrand disease?

Answer 20

Spontaneous bleeding - particularly epistaxes (nosebleeds), gum bleeding and menorrhagia
There can also be easy bruising (ecchymosis)

Question 21

What test can be involved in the diagnosis of Von Willebrand disease?

Answer 21

FBC, APTT, functional assay of vWF and Factor VIII:C assay

Question 22

What drug can be used to treat significant bleeding in Von Willebrand disease?

Answer 22

Desmospressin

Question 23

Besides haemophilia and Von Willebrand disease, what can cause bleeding disorders?

Answer 23

Liver failure
Vitamin K deficiency
Autoimmunity against clotting factors
Disseminated intravascular coagulation