Case 6 - Clotting Disorders - Progress Test

Question 1

What would blood tests show for vWD?

Answer 1

• Prolonged bleeding time
• May have a prolonged APTT
• May have slightly decreased factor VIII
• Defective platelet aggregation

Normal PT

Question 2

What would blood tests show in haemophilia?

Answer 2

• Prolonged APTT

- Normal bleeding time, thrombin time and PT

Question 3

What would blood tests show in thalassaemia?

Answer 3

Microcytic anaemia

Haemoglobin electrophoresis - globin abnormalities

DNA testing - genetic abnormality

Question 4

Is thalassaemia dominant or recessive?

Answer 4

Recessive

Question 5

Is vWD dominant or recessive?

Answer 5

Dominant

Apart from type 3 which is recessive

Question 6

How is haemophilia treated?

Answer 6

IV infusions of the missing clotting factor (factor VIII or IX)

Acute bleeds:

• Infusions of clotting factor
• Desmopressin (stimulates the release of vWF)
• Antifibrinolytics (eg. transexamic acid)

Question 7

What are the types of haemophilia?

Answer 7

Type A (factor VIII) 
Type B (factor IX)

Question 8

How is vWD treated?

Answer 8

Transexamic acid for mild bleeding

Desmopressin (increases level of vWF)

Factor VIII concentrate

Question 9

What are the types of vWD?

Answer 9

Type 1 - partial reduction in vWF

Type 2 - abnormal vWF

Type 3 - absence of vWF

Question 10

What are complications of thalassaemia?

Answer 10

Splenomegaly (due to fragile blood cells which break down more easily)

Expanded bone marrow (from production of extra red blood cells)
- Causes susceptibility to fracture and prominent features (eg. pronounced forehead / cheekbones)

Question 11

What are complications of thalassaemia?

Answer 11

Splenomegaly (due to fragile blood cells which break down more easily)

Expanded bone marrow (from production of extra red blood cells)
- Causes susceptibility to fracture and prominent features (eg. pronounced forehead / cheekbones)

Iron overload due to faulty creation of RBCs, recurrent transfusions and increased absorption of iron in response to the anaemia

Question 12

How is alpha thalassaemia managed?

Answer 12

• Blood transfusions
• Splenectomy
• Bone marrow transplant can be curative
• monitor FBC for iron overload

Question 13

How is beta thalassaemia trait managed?

Answer 13

• Monitoring

- Ususally no treatment required

Question 14

How is beta thalassaemia major managed?

Answer 14

Regular transfusions

Iron chelation

Splenectomy

Bone marrow transplant

Question 15

What things in the blood are anticoagulants?

Answer 15

Protein C
Protein S
Antithrombin

Question 16

What are the stages of haemostasis?

Answer 16

Primary - formation of the platelet plug

Secondary - activation of clotting factors and formation of the fibrin (factor 1a) mesh

Question 17

Factors involved in the intrinsic pathway

Answer 17

Faction XII
Factor XI
Factor IX
Factor VIII

Question 18

Factors involved in the extrinsic pathway

Answer 18

VII

Question 19

Factors involved in the common pathway

Answer 19

Factor X
Factor II (Prothrombin)
Factor I (Fibrinogen)
XIII

Question 20

What clotting factors are activated by vitamin K?

Answer 20

Factor II, VII, IX, X

Proteins C, S, Z

Question 21

Does APPT show the intrinsic or extrinsic pathway?

Answer 21

Intrinsic

Question 22

Does APTT show the intrinsic or extrinsic pathway?

Answer 22

Intrinsic

Question 23

What causes a prolonged PT?

Answer 23

Liver disease
DIC
Vitamin K deficiency
Warfarin levels

Question 24

What causes a prolonged APPT?

Answer 24

Haemophillia
vWD
Heparin

Question 25

What causes a prolonged APTT?

Answer 25

Haemophillia
vWD
Heparin

Question 26

What causes a prolonged PT and APTT?

Answer 26

Vitamin K deficiency - liver disease / malabsorption
DIC
Rare - factor V or X

Question 27

What causes a prolonged thrombin time?

Answer 27

DIC
Liver disease
Malnutrition