Bleeding Disorders

Question 1

What are the three categories of platelet plug failure?

Answer 1

• vascular (collagen deficiency)
• platelets
• Von Willebrand Factor

Question 2

Name the vascular causes of platelet plug failure

Answer 2

Hereditary - marfans
Vasculitis - HSP
Ageing - loss of collagen - senile purpura
Vitamin C deficiency

Question 3

Name the causes of thrombocytopenia

Answer 3

Hereditary - rare
Reduced production - pancytopenia due to marrow failure
Increased destruction

Question 4

What can cause peripheral platelet destruction?

Answer 4

Coagulopathy e.g DIC
Autoimmune e.g immune thrombocytopenic purpura
Hypersplenism

Question 5

Describe immune thrombocytopenic purpura

Answer 5

Antibodies against platelets (<1 day life span)

Question 6

What can cause hypersplenism?

Answer 6

Liver disease and portal hypertension leads to trapping of platelets

Question 7

Name the functional defects that can increase destruction of platelets

Answer 7

Drugs - aspirin, NSAIDs

Renal failure

Question 8

How can vWF deficiency arise?

Answer 8

Acquired in autoimmune

Hereditary - autosomal dominant, variable severity

Question 9

What can cause failure of fibrin clot?

Answer 9

Multiple clotting factor deficiencies

Single clotting factor deficiency

Question 10

Name the causes of multiple clotting factor deficiencies

Answer 10

Liver disease
Vitamin K deficiency/Warfarin
Complex coagulopathy

Question 11

Which clotting factors will be reduced in vitamin K deficiency?

Answer 11

II, VII, IX, X

Question 12

What will PT and APTT be when there are multiple clotting factor deficiencies?

Answer 12

Prolonged

Question 13

Where are clotting factors made?

Answer 13

Hepatocytes in the liver

Question 14

What is the function of vitamin K?

Answer 14

Carboxylates factors II, VII, IX and X which is essential for their function

Question 15

How do we get vitamin K into the blood stream?

Answer 15

Diet and bowel bacteria produce it

Absorbed by upper intestine and requires bile salts

Question 16

What can cause vitamin K deficiency?

Answer 16

Diet
Malabsorption - Crohn’s
Obstructive jaundice due to lack of bile salts (pancreatic cancer/gallstones)
Warfarin
Haemorrhage disease of the newborn (no bowel bacteria or presence in diet)

Question 17

How is haemorrhage disease of the newborn prevented?

Answer 17

IM vitamin K

Question 18

What is DIC?

Answer 18

Disseminated intravascular coagulation
Excessive and inappropriate activation of haemostatic system causing microvascular thrombus formation and end organ failure

Question 19

How does DIC present?

Answer 19

Clotting factor consumption - fibrinolysis causing bruising, purpura, bleeding
Significantly raised APTT and PT
Really low fibrinogen

Question 20

What can cause DIC?

Answer 20

Sepsis
Obstetric emergency
Malignancy
Hypovolaemic shock

Question 21

How is DIC treated?

Answer 21

Manage underlying cause

Replacement therapy - transfusion

Question 22

How will platelet failure present?

Answer 22

Purpura in lower limbs, mucosal bleeding, retinal haemorrhages

Question 23

What mode of inheritance is haemophilia?

Answer 23

X linked

Question 24

What are the two types of haemophilia?

Answer 24

A - factor VIII deficiency

B - factor IX deficiency

Question 25

Describe haemophilia

Answer 25

Abnormally prolonged bleeding recurs episodically at one or a few sites on each occasion

Question 26

Which joints are typically affected in haemophilia?

Answer 26

Load bearing - ankles and knees

Question 27

What will PT and APTT be in haemophilia?

Answer 27

PT normal

APTT prolonged

Question 28

Name the clinical features of haemophilia

Answer 28

Recurrent haemarthroses
Recurrent soft tissue bleeds - bruising in kids
Prolonged bleeding after dental extraction/surgery/invasive procedures

Question 29

How does a ‘target joint’ develop?

Answer 29

Iron deposition, inflammation and neovascularisation can eventually lead to joint fusion

Question 30

How is haemophilia managed?

Answer 30

Replacement of clotting factors by IV injection every couple of days