Lecture 6: Haemostasis Flashcards
Name two vascular disorders
Vascular bleeding
Hereditary haemorrhagic telangiectasia
Give inherited and acquired causes of vascular bleeding
Inherited:
- Hereditary haemorrhagic telangiectasia
- Ehlers-Danlos syndrome
Acquired:
- Scurvy
- Steroids
- Senile
Name the disorder of low platelets
Thrombocytopaenia
Normal range 150-400x10^9/L
Symptoms when platelets <10
Epistaxis, GI bleeds, menorrhagia, bruising
Inherited causes of thrombocytopenia
Rare
Acquired causes of thrombocytopenia
ITP, drug-related, DIC
Name inherited and acquired disorders of platelet function
Inherited:
- Many rare diagnoses e.g. Glanzmann’s
Acquired:
- Drugs e.g. aspirin, NSAIDs
Name inherited and acquired disorders of coagulation
Inherited:
- Inherited haemophilia
Acquired:
- Non-inherited causes of haemophilia (liver disease, DIC)
- Anti-coagulant drugs
- Vitamin K deficiency
What causes haemophilia A and what causes haemophilia B?
A - 8
B - 9
Both x-linked conditions affecting males only
What are the clinical features of haemophilia?
Spontaneous bleeding into joints and muscle
Unexpected post-op bleeding
Chronic debilitating joint disease
Major haematoma
Haemarthritis
What is APTT?
Assess the intrinsic pathway
Tests factors VIII, IX, XI XII
What is PT?
Assesses the extrinsic pathway
Tests factors II, V, VII, X
What would the APTT and PT be for haemophilia?
APTT - prolonged
PT - normal
What is von willebrand disease?
Autosomal dominant
vWF - large multimeric protein that carries factor VIII in the blood
vWF also binds platelets to endothelial collagen
vWD = deficiency of vWF and FVIII in plasma
Mucocutaneous, nosebleeds, menorrhagia
What would the APTT and PT be for vWD?
APTT - prolonged PT - normal Also Low vWF level Low FVIII Prolonged bleeding time Defective platelet function
Treatment with desmopressin, anti-fibrinolytic and plasma products
What would the APTT and PT be for meningococcal DIC?
PT - prolonged APTT - prolonged TT - prolonged Also Low fibrinogen, low platelets, raised D-dimers
