Bleeding tendencies

Question 1

What is the most common cause of an inherited haemophilia?

Answer 1

Von Willebrand disease.

Question 2

What is the most common cause of inherited thrombophilia?

Answer 2

Activated protein C resistance.

Question 3

How is Von Willebrand factor involved in clotting?

Answer 3

It is involved in platelet adhesion; it binds to collagen that is exposed in the vessel.

Is also a carrier for clotting factor VIII and helps to stabilise this clotting factor.

Question 4

How does Von Willebrand disease often present?

Answer 4

With minor problems such as epistaxis, easy bruising, menorrhagia and bleeding after minor trauma or surgery (for example, after tooth extraction).

Question 5

Which blood tests are you likely to be interested in for a patient with suspected Von Willebrand disease and what would the results be if a patient had Von Willebrand disease?

Answer 5

• Prolonged APTT
• Prolonged PT
• Increased bleeding time
• Reduded factor VIII
• Reduced VWF

Question 6

Which blood tests are you likely to be interested in for a patient with suspected Von Willebrand disease and what would the results be if a patient had Von Willebrand disease?

Answer 6

• Prolonged APTT
• Prolonged PT
• Increased bleeding time
• Reduded factor VIII
• Reduced VWF
• *APTT is a reflection of the intrinsic pathway.
• **Factor VIII is involved in the intrinsic pathway.

Question 7

1) Patients with haemophilia A and deficient in what?
2) Patients with haemophilia B are deficient in what?
3) What type of inheritance pattern do the haemophilias have?

Answer 7

1) Clotting factor 8.
2) Clotting factor 9.
3) X-linked recessive.

Question 8

How can haemophilia present in neonates?

Answer 8

Intracranial haemorrhage, haematomas and prolonged bleeding after circumcision.

Question 9

What is a feature of severe haemophilia and what can this lead to?

Answer 9

Haemarthrosis is a feature of severe haemophilia which can lead to joint deformity.

Question 10

1) What might blood tests show in people with haemophilia?

2) How is a diagnosis of haemophilia made?

Answer 10

1) Prolonged APTT but normal PT.

2) By factor VIII or factor IX assays.

Question 11

1) What might blood tests show in people with haemophilia?

2) How is a diagnosis of haemophilia made?

Answer 11

1) Prolonged APTT (as tests intrinsic and common pathways) BUT normal PT (because PT measures extrinsic and common pathways).
2) By factor VIII or factor IX assays.

Question 12

Why can desmopressin be helpful in patients with mild factor VIII deficiency?

Answer 12

Because it stimulates VWF release from endothelial cells which promotes stabilisation of residual factor VIII.

Question 13

In addition to medications, what other management is required for patients with haemophilia?

Answer 13

Avoid NSAIDs, Heparin and Warfarin as these can promote bleeding.
Avoid contact sports.

Question 14

Name 2 acquired coagulation disorders.

Answer 14

1) Vitamin K deficiency

2) Liver disease

Question 15

State 4 causes of vitamin K deficiency.

Answer 15

1) Haemorrhagic disease of the newborn.
2) Severe malnutrition
3) Malabsorption (cholestatic jaundice)
4) Warfarin.

Question 16

State 3 causes of coagulation disorders which occur in the liver.

Answer 16

1) Reduced synthesis.
2) Thrombocytopenia due to hypersplenism (causes portal HTN).
3) DIC.

Question 17

What are the 3 main categories of cause of thrombocytopenia?

Answer 17

1) Impaired production of platelets
2) Excessive destruction of platelets.
3) Sequestration of platelets in an enlarged spleen (splenomegaly/ hypersplenism).

Question 18

Give 3 causes of impaired production go platelets.

Answer 18

Bone marrow failure
Myelodysplastic syndromes
Myeloma
Aplastic anaemia
HIV

Question 19

Give 3 causes of excessive destruction of platelets.

Answer 19

• Immune/ idiopathic thrombocytopenia purpura.
• SLE/CLL/ viruses/ heparin
• Alloimmune neonatal thrombocytopenia
• DIC
• Thrombotic thrombocytopenia purpura

Question 20

What is the difference between immune/ idiopathic and thrombotic thrombocytopenia purpura?

Answer 20

Immune/ idiopathic = bleeding due to destruction of platelets (body destroys platelets).

Thrombotic = Clotting due to platelets being used up

Question 21

1) What can thrombotic thrombocytopenia purpura cause?

2) What causes immune/idiopathic thrombocytopenia purpura?

Answer 21

1) Fever, haemolytic anaemia and low platelet count. The cause is unknown.
2) Antibodies against GPIIb/IIIa receptor. Can occur in children who have had a recent viral illness.

Question 22

What does disseminated intravascular coagulation arise due to?

Answer 22

Systemic activation of coagulation, often as part of an inflammatory response. It can be a sign of a serious, life-threatening underlying illness.

Question 23

Give 3 conditions which can potentially lead to DIC.

Answer 23

Cancer
Septicaemia
Haemolytic infusion reactions
Obstetric complications
Trauma, burns and surgery
Liver disease

**DIC only happens in seriously unwell patients.

Question 24

Why can DIC cause both bleeding and thrombosis?

Answer 24

Can cause bleeding due to the condition using up all of the coagulation factors and clotting as there is less anticoagulant.

Question 25

Generally, what happens in haemophilia?

Answer 25

Secondary haemostasis (formation of fibrin mesh) occurs at a much slower rate than normal, causing increased bleeding.

Question 26

1) Deficiency in which factor is asymptomatic?

2) What happens in severe Von Willebrand disease?

Answer 26

1) Factor XII
2) CF VIII gets broken down faster than normal and so patients can become deficient in factor VIII (why VWD can mimic haemophilia A).

Question 27

1) Which clotting factors does the liver synthesise?

2) Vitamin K is needed to synthesise and release which clotting factors?

Answer 27

1) All except from III. IV, VI and IX.

2) II, VII, IX, X.

Question 28

State 5 clinical features associated with haemophilia.

Answer 28

Ecchymosis
Haematomas
Prolonged bleeding after a cut or surgery.
Blood oozing after tooth extraction. 
GI Bleeding
Haematuria
Epistaxis
Haemarthrosis
Brain bleeds

Question 29

1) What bleeding disorder might malabsorption cause?

2) How is this bleeding tendency treated?

Answer 29

1) Vitamin K deficiency.

2) IV Vitamin K (10mg) or in acute haemorrhage, with human prothrombin complex or FFP.

Question 30

Aside from malabsorption, name 4 other causes of vitamin K deficiency.

Answer 30

Drugs (e.g. warfarin)
Malnutrition
Alcoholism
Cystic fibrosis
CKD
Cholestatic disease

Question 31

What blood test results might you see in a patient with vitamin K deficiency?

Answer 31

Increased PT

Increased or normal APTT.