Bleeding Disorders

Question 1

What is haemostasis?

Answer 1

The cessation of bleeding following trauma to blood vessels.

Question 2

What is FIII?

Answer 2

Tissue factor

Question 3

What is FII?

Answer 3

Prothrombin

Question 4

What are the principle haemostatic mechanisms?

Answer 4

Platelet aggregation, fibrin polymerisation and vasoconstriction

Question 5

What are platelets?

Answer 5

Small anucleate fragments

Question 6

What are platelets derived from?

Answer 6

Megakayocytes

Question 7

What do platelets respond to?

Answer 7

A variety of chemical stimuli

Question 8

What do platelets circulate as?

Answer 8

Resting disks

Question 9

What is VWF?

Answer 9

An adhesion molecule present in plasma and subendothelial matrix

Question 10

What is fibrinogen?

Answer 10

An adhesion molecule present in the plasma

Question 11

What does coagulation mean?

Answer 11

The solidification of liquid plasma

Question 12

What is FIIa?

Answer 12

Thrombin

Question 13

What is FI?

Answer 13

Fibrinogen

Question 14

What is the coagulation cascade initiated by?

Answer 14

The exposure of blood (plasma) to a trigger which sets off a series of enzymes reactions

Question 15

What is the final step in the coagulation cascade?

Answer 15

Polymerisation of fibrin monomers to format a gel like mesh

Question 16

Why is there no factor IV?

Answer 16

Factor VI was discovered as calcium ions but by this time factor V had already been named

Question 17

What can bleeding disorders be a result of?

Answer 17

Primary or secondary haemostasis

Question 18

What is primary haemostasis?

Answer 18

Formation of a platelet plug

Question 19

What is secondary haemostasis?

Answer 19

Consolidation of the thrombus by fibrin strands

Question 20

What are the disorders of primary haemostasis?

Answer 20

Platelet disorders (thrombocytopenia, platelet dysfunction), von willebrands disease, connective tissue disorder

Question 21

What are the disorders of secondary haemostasis?

Answer 21

Clotting factor deficiencies (haemophilias, liver disease), anti coagulant overdose, overactive fibrinolysis

Question 22

What are the patterns of bleeding from primary haemostatic disorders?

Answer 22

Bleeding from skin wounds, bleeding from mucous membranes, GI bleeds, surgical bleeding, cranial haemorrhages (rare)

Question 23

What are the patterns of bleeding from secondary haemostatic disorders?

Answer 23

Haemoarthrosis (joints), intramuscular bleeding, cranial haemorrhages (rare)

Question 24

What can be noted in thrombocytopenia?

Answer 24

Low platelet count, impaired bone marrow function, autoimmunological destruction

Question 25

What can be noted in Von Willebrand's disease?

Answer 25

Qualitative or quantitative deficiency in Von Willebrand's factor, reduced circulating factor VIII

Question 26

What can be noted in Glanzmann's thrombocytopenia/bernard-soulier syndrome?

Answer 26

Autosomal inheritance with varying severity, caused by defects in VWF gene.

Question 27

What is thrombocytopenia?

Answer 27

Most common cause of defective primary haemostasis

Question 28

Platelet + autoantibodies ➡ sensitised platelet = ?

Answer 28

Destroyed by macrophage

Question 29

Haemophilia A is caused by?

Answer 29

FVIII deficiency

Question 30

Haemophilia B is caused by?

Answer 30

FIX deficiency

Question 31

What is haemophilia C caused by?

Answer 31

FXI deficiency, liver disease, vitamin k deficiency, warfarin overdose