Bleeding Disorders

Question 1

What are the broad causes of failure of platelet plug formation?

Answer 1

Vascular abnormalities
Reduced platelet number/function
Reduced vWF

Question 2

Which vasculitis can result in failure of platelet plug formation?

Answer 2

Henoch-Schonlein purpura

Question 3

What is the medical term for low levels of platelets?

Answer 3

Thrombocytopenia

Question 4

What coagulopathy can result in peripheral platelet destruction?

Answer 4

Disseminated intravascular coagulation

Question 5

What autoimmune disorder can cause peripheral platelet destruction?

Answer 5

Immune thrombocytopenic purpura

Question 6

Why may portal hypertension result in increased platelet destruction?

Answer 6

As the blood backing up causes hypersplenism increasing platelet destruction

Question 7

What drugs may cause platelet functional defects?

Answer 7

Aspirin

NSAIDs

Question 8

Why may renal failure cause platelet functional defects?

Answer 8

As uraemia can interfere with platelet function

Question 9

Multiple clotting factor deficiencies are generally acquired/hereditary

Answer 9

Acquired

Question 10

Give some causes of multiple clotting deficiencies

Answer 10

DIC
Liver failure
Vitamin K deficiency

Question 11

What is the main cause of a single clotting factor deficiency?

Answer 11

Haemophilia

Question 12

Why does liver failure cause a multiple factor deficiency?

Answer 12

As all clotting factors are produced in the liver

Question 13

A vitamin K deficiency will affect which clotting factors?

Answer 13

II, VII, IX and X

Question 14

In multiple factor deficiencies, only prothrombin time will be prolonged. True/false?

Answer 14

False - both PT and APTT prolonged

Question 15

Give some causes of vitamin K deficiency

Answer 15

Diet (no green leafy veg)
Malabsorption (Crohn's)
Obstructive jaundice
Warfarin therapy
Haemorrhagic disease of the newborn

Question 16

What occurs in disseminated intravascular coagulation?

Answer 16

There is excessive activation of the haemostatic system causing microvascular thrombus formation and clotting factor consumption

Question 17

Give some causes of DIC

Answer 17

Sepsis
Obstetric emergencies
Malignancy
Trauma
Hypovolaemic shock

Question 18

A prolonged prothrombin time suggests what is affected?

Answer 18

Tissue factor

Factor VIIa

Question 19

A prolonged activated partial thromboplastin time suggests what is affected?

Answer 19

Factors VIII/IXa

Question 20

What breaks down fibrin into fibrin degradation products?

Answer 20

Plasmin

Question 21

What are fibrin degradation products measured as in the lab?

Answer 21

D-dimers

Question 22

How is DIC treated?

Answer 22

Treat underlying cause

Replace platelets, plasma and fibrinogen

Question 23

Only men/women are affected by haemophilia

Answer 23

Men - X-linked disorder

Question 24

Haemophilia A and B are deficiencies of which factors?

Answer 24

A - VIII

B - IX

Question 25

What parts of the body are most commonly affected by haemophilia?

Answer 25

Joints under most strain - tends to be ankle and knee

Question 26

Give some clinical features of severe haemophilia

Answer 26

Recurrent haemarthroses Recurrent soft tissue bleeds Prolonged bleeding after surgery

Question 27

In moderate haemophilia what is the level of factor VIII?

Answer 27

2-5%