Case 6 - Clotting Disorders - Progress Test Flashcards
What would blood tests show for vWD?
- Prolonged bleeding time
- May have a prolonged APTT
- May have slightly decreased factor VIII
- Defective platelet aggregation
Normal PT
What would blood tests show in haemophilia?
- Prolonged APTT
- Normal bleeding time, thrombin time and PT
What would blood tests show in thalassaemia?
Microcytic anaemia
Haemoglobin electrophoresis - globin abnormalities
DNA testing - genetic abnormality
Is thalassaemia dominant or recessive?
Recessive
Is vWD dominant or recessive?
Dominant
Apart from type 3 which is recessive
How is haemophilia treated?
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)
What are the types of haemophilia?
Type A (factor VIII) Type B (factor IX)
How is vWD treated?
Transexamic acid for mild bleeding
Desmopressin (increases level of vWF)
Factor VIII concentrate
What are the types of vWD?
Type 1 - partial reduction in vWF
Type 2 - abnormal vWF
Type 3 - absence of vWF
What are complications of thalassaemia?
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)
What are complications of thalassaemia?
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
How is alpha thalassaemia managed?
- Blood transfusions
- Splenectomy
- Bone marrow transplant can be curative
- monitor FBC for iron overload
How is beta thalassaemia trait managed?
- Monitoring
- Ususally no treatment required
How is beta thalassaemia major managed?
Regular transfusions
Iron chelation
Splenectomy
Bone marrow transplant
What things in the blood are anticoagulants?
Protein C
Protein S
Antithrombin
What are the stages of haemostasis?
Primary - formation of the platelet plug
Secondary - activation of clotting factors and formation of the fibrin (factor 1a) mesh
Factors involved in the intrinsic pathway
Faction XII
Factor XI
Factor IX
Factor VIII
Factors involved in the extrinsic pathway
VII
Factors involved in the common pathway
Factor X
Factor II (Prothrombin)
Factor I (Fibrinogen)
XIII
What clotting factors are activated by vitamin K?
Factor II, VII, IX, X
Proteins C, S, Z
Does APPT show the intrinsic or extrinsic pathway?
Intrinsic
Does APTT show the intrinsic or extrinsic pathway?
Intrinsic
What causes a prolonged PT?
Liver disease
DIC
Vitamin K deficiency
Warfarin levels
What causes a prolonged APPT?
Haemophillia
vWD
Heparin
What causes a prolonged APTT?
Haemophillia
vWD
Heparin
What causes a prolonged PT and APTT?
Vitamin K deficiency - liver disease / malabsorption
DIC
Rare - factor V or X
What causes a prolonged thrombin time?
DIC
Liver disease
Malnutrition
