34 Questions
What is the most common type of hemophilia?
Hemophilia A
What is the mode of inheritance of hemophilia A and B?
X-linked recessive
What percentage of hemophilia cases are caused by new mutations?
1/3
Which of the following is NOT a clinical presentation of hemophilia?
Hematemesis
What is the deficiency in hemophilia C?
Factor 11
What is the pathway that involves tissue factor (TF) and factor VIIa?
Extrinsic pathway
What is the order of increasing concentration of clotting factors in the following treatment preparations?
Whole blood, plasma, cryoprecipitate, factor concentrates
Which of the following is a complication of hemophilia?
All of the above
What is the treatment for Factor XI deficiency?
Fibrinolytic inhibitor, Tranexamic acid, and factor XI concentrate
Which of the following is a characteristic of Von Willebrand disease?
Autosomal dominant inheritance
What is the role of VWF in the coagulation process?
Carrier for factor 8, platelets adhesion to vascular collagen
Which population is more prone to Factor XI deficiency?
Ashkenazi Jews
What is the primary goal of hemophilia therapy?
To treat and prevent bleeding episodes and related complications
What is the benefit of regular prophylaxis in hemophilia therapy?
Reduced physical impairment from hemophilic arthropathy
What is the target trough factor level in blood for standard prophylaxis regimens?
1-2%
What is the purpose of immobilization of a limb in hemophilia treatment?
To relieve pain and stabilize the clot
What laboratory investigation is normal in hemophilia?
Platelet number and function
What is the purpose of factor assay in hemophilia diagnosis?
To measure the concentration of factors 8, 9, 11, and VWF
What should be avoided in hemophilia treatment to prevent bleeding?
Surgical intervention or invasive diagnostic procedures
What is the intrinsic pathway involved in?
Coagulation cascade
What is the most common presentation of bleeding in females with Von Willebrand disease?
Menorrhagia and mucocutaneous bleeding
What is the expected result of a Platelet function test in Von Willebrand disease?
Abnormal adhesion
What is the purpose of Tranexamic acid in the treatment of Von Willebrand disease?
To inhibit fibrinolysis
What is the underlying mechanism of Disseminated Intravascular Coagulation?
All of the above
What is the characteristic finding on blood film examination in patients with Disseminated Intravascular Coagulation?
Red cell fragmentation
What is the expected result of the Thrombin time test in patients with Disseminated Intravascular Coagulation?
Prolonged
What is the primary indication for the use of Cryoprecipitate in patients with Disseminated Intravascular Coagulation?
Bleeding
What is the percentage of patients with Disseminated Intravascular Coagulation who manifest thrombotic lesions?
5-10%
What is the purpose of administering heparin or antiplatelet drugs to patients with thrombotic problems?
To inhibit the coagulation process
Which of the following is an inherited thrombophilia?
Protein C deficiency
What is the significance of a prolonged APTT in the investigation of thrombophilia?
It suggests the presence of an anticoagulant
What is the mechanism of action of warfarin in the treatment of thrombophilia?
It inhibits the production of vitamin K
What is a common side effect of heparin therapy?
Osteoporosis
What is the significance of recurrent venous thrombosis in a young patient?
It is indicative of inherited thrombophilia
Study Notes
Haemophilia
- Inherited coagulation factor defect, affecting 1 in 5,000 to 1 in 10,000 males
- Three types: Haemophilia A (factor 8), Haemophilia B (factor 9), Haemophilia C (factor 11)
- Von Willebrand disease (VWF) is also an inherited bleeding disorder
Inheritance of Haemophilia
- X-linked recessive disease, affecting males
- 1/3 of cases develop post-new mutations, with no family history
- Haemophilia A is the most common, with Haemophilia B accounting for 20% of cases
Clinical Presentation
- Petechiae, purpura, hematoma, joint bleeding, mucocutaneous bleeding, intracranial hemorrhage, post-tooth extraction bleeding, post-operative bleeding, trauma
- Advanced joint and muscle bleeding
Laboratory Investigation
- Normal platelet count and function
- Normal PT, PC, INR
- Prolonged APTT
- Factor assay (8, 9, 11, VWF)
Treatment
- "On-demand" or prophylaxis
- Aimed at treating and preventing bleeding episodes and related complications
- Regular prophylaxis started at an early age can reduce physical impairment from hemophilic arthropathy
Complications of Haemophilia
- Arthropathy, deformity
- Muscle atrophy, nerve compression, limb ischemia
- Fatal ICH bleeding
- Pseudotumor (subperiosteal bleeding, new bone formation)
- Infection (HCV, HBV, HIV) due to plasma product
Factor XI Deficiency
- Ashkenazi Jews, affects both sexes
- Bleeding risk shows incomplete correlation to severity of deficiency
- Treatment: fibrinolytic inhibitor (tranexamic acid), factor XI concentrate, or fresh frozen plasma
Von Willebrand Disease
- VWF carries factor 8, platelets adhere to vascular collagen
- Most common inherited bleeding disorder
- Autosomal dominant inheritance
- Affects females, presenting with mucocutaneous bleeding
- Menorrhagia, epistaxis, rare hemarthrosis, and muscle bleeding
Laboratory Diagnosis
- Normal CBC, normal PT, normal TT
- Prolonged APTT
- VWF antigen, activity
- Factor 8 level (type III VWD)
- Platelet function test abnormal adhesion
Treatment
- Supportive: avoid antiplatelets (aspirin), anticoagulants (warfarin), fibrinolytic inhibitor (tranexamic acid)
- Cryoprecipitate, plasma, vasopressin (type 1 VWD)
- VWF/factor 8 concentrate
Acquired Coagulation Factors
- Disseminated intravascular coagulation
- Widespread inappropriate intravascular deposition of fibrin with consumption of coagulation factors and platelets
- Associated with many disorders, e.g., leukemia, trauma, obstetric complications
Clinical Presentation
- Bleeding, thrombotic lesions, organ dysfunction
- 5-10% of patients manifest thrombotic lesions
Laboratory Investigation
- Low platelet count
- Low fibrinogen concentration
- Prolonged thrombin time
- High levels of fibrin degradation products (D-dimers) in serum and urine
- Prolonged PT and APTT
Treatment
- Bleeding: supportive therapy with fresh frozen plasma and platelet concentrates
- Thrombosis: heparin or antiplatelet drugs to inhibit coagulation process
Thrombophilia
- Inherited: anti-thrombin III, protein C deficiency, protein S deficiency, factor V Leiden
- Acquired: dyslipidemia, malignancy, nephrotic syndrome, Behcet's syndrome, antiphospholipid antibody syndrome, pregnancy, COC, PNH, myeloproliferative disorder, leukemia
Clinical Picture and Investigation
- Recurrent venous thrombosis, abnormal site, young age
- Arterial thrombosis, absence of arterial atherosclerosis
- Recurrent abortion
- Thrombophlebitis
- Investigation: prolonged APTT, anticardiolipin antibody, lupus anticoagulant, level of protein S, C, anti-thrombin III, factor V Leiden
Treatment
- Anticoagulant: oral warfarin (vitamin K antagonist), parenteral heparin (subcutaneous, intravenous, unfractionated, low molecular weight)
- Side effects: heparin-induced thrombocytopenia, osteoporosis
This quiz covers the pathophysiology of haemophilia, including the intrinsic and extrinsic pathways of blood coagulation. Test your knowledge of the clotting factors and their interactions.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
