Bleeding disorders

Question 1

What is the platelet count of someone with thrombocytopenia?

Answer 1

<150x10^9/L

Question 2

What is the platelet count of someone who would be treated for thrombocytopenia?

Answer 2

<50x10^9/L

Question 3

What are the main causes of thrombocytopenia?

Answer 3

• Failure of marrow production
• Shortened lifespan
• Dilution
• Sequestration

Question 4

What is sequestration?

Answer 4

Pooling of platelets in spleen

Question 5

What is the mechanism for acute idiopathic thrombocytopenic purpura?

Answer 5

• Sudden onset after trivial illness
• Platelet will attach viral antigens to itself

Question 6

What is the mechanism for chronic idiopathic thrombocytopenic purpura?

Answer 6

• Gradual onset
• Autoantibodies against platelet membranes
• Platelets destroyed in spleen hours after being ,made

Question 7

How is acute idiopathic thrombocytopenic purpura treated?

Answer 7

No treatment, Patient is just observed

Question 8

How is chronic idiopathic thrombocytopenic purpura treated?

Answer 8

• Corticosteroids
• Splenectomy
• Stem cell transplant

Question 9

What causes thrombotic thrombocytopenic purpura?

Answer 9

Formation of von willebrand factor multimers which lead to thrombosis

Question 10

How do you diagnose thrombotic thrombocytopenic purpura?

Answer 10

Look out for:
- Thrombocytopenia
- Schistocytis (fragmented rbcs)

Question 11

How is thrombotic thrombocytopenic purpura treated?

Answer 11

• Plasma exchange to remove the VWF multimers

Question 12

What is disseminated intravascular coagulation?

Answer 12

• Widespread innapropriate intravascular deposition of fibrin
• Consumption of coagulation factors and platelets

Question 13

What does disseminated intravascular coagulation result in?

Answer 13

Thrombocytopenia and bleeding

Question 14

What causes disseminated intravascular coagulation?

Answer 14

Typically it’s secondary to other causes:
- Infections
- Malignancy
- Tissue damage

Question 15

How is disseminated intravascular coagulation treated?

Answer 15

-Depends on whether patient is bleeding (fresh frozen plasma) or thrombotic (heparin)

Question 16

Give an example of an inhereted platelet disorder

Answer 16

Von willebrand disease

Question 17

What is Von willebrand disease?

Answer 17

A low volume of vWF factors leading to premature destruction of platelets and clots not forming

Question 18

What are the signs and symptoms of vWF Disease

Answer 18

Frequent nose bleeds
easy bruising
heavy menstural bleeding

Question 19

How is vWF diagnosed?

Answer 19

Activated partial thromboplastin time being prolonged

Question 20

What is the treatment for vWF disease?

Answer 20

Generally no treatment is required

Question 21

What is Glanzmann’s thrombasthenia?

Answer 21

Inability of platelets to bind to fibrinogen, preventing the formation of the platelet plug

Question 22

How is Glanzmann’s thrombasthenia diagnosed?

Answer 22

Check to see if platlets will react to any type of antagonist

Question 23

What is the interaction between asparin and platelets?

Answer 23

Asparin irreversably acelates cyclooxygenase 1 which usually catalayses thromboxane A2

Question 24

What factor deficiency is Haemophilia A associated with

Answer 24

8

Question 25

How is Haemophilia A diagnosed?

Answer 25

Activated partial thromboplastin abnormally long time

Question 26

How is haemophilia A treated?

Answer 26

Prophylactic infusions of factor VIII

Question 27

What is the prognosis for someone with haemophilia A?

Answer 27

Near normal life expectancy, but they should avoid competitive sports

Question 28

What factor deficieny is Haemophilia B associated with?

Answer 28

9