Thrombotic Disorders
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Questions and Answers

What is the correct sequence of steps involved in normal haemostasis after blood vessel injury?

  • Platelet activation, Platelet aggregation, Coagulation, Platelet secretion
  • Collagen exposed, Platelet adhesion, Platelet activation, Fibrin strands trap cells
  • Collagen exposed, Platelet adhesion, Platelet activation, Platelet secretion, Platelet aggregation, Coagulation (correct)
  • Coagulation, Platelet adhesion, Collagen exposed, Platelet aggregation

    • Which of the following is a pathological consequence of arterial thrombosis?

  • Deep Vein Thrombosis
  • Pulmonary Embolism
  • Varicose Veins
  • Myocardial Infarction (correct)

    • What initiates the process of platelet activation following blood vessel injury?

  • Exposure of collagen (correct)
  • Aggregation of platelets
  • Formation of thrombus
  • Secretion of fibrinogen

    • Which of the following symptoms is indicative of ischaemic stroke related to arterial thrombosis?

    <p>Sudden difficulty with vision</p> Signup and view all the answers

    In the context of arterial thrombosis, what role do fibrin strands play?

    <p>They trap cells to form a stable clot</p> Signup and view all the answers

    What is a common probable cause of arterial thrombosis?

    <p>Inappropriate activation of platelets</p> Signup and view all the answers

    What symptom is associated with peripheral arterial disease (PAD)?

    <p>Pain or cramping in the legs during activity</p> Signup and view all the answers

    Which factor primarily contributes to the inappropriate activation of platelets in arterial thrombosis?

    <p>Atherosclerosis</p> Signup and view all the answers

    What symptom is commonly associated with myocardial infarction (MI) that may radiate to different parts of the body?

    <p>Central chest pain</p> Signup and view all the answers

    What is one sign of arterial thrombosis in the case of ischemic stroke?

    <p>Slurred speech</p> Signup and view all the answers

    Which diagnostic method is essential for confirming an ischemic stroke?

    <p>Neuroimaging (CT or MRI)</p> Signup and view all the answers

    What treatment option is typically used for arterial thrombosis in the case of myocardial infarction?

    <p>Thrombolytic therapy</p> Signup and view all the answers

    What does Virchow's Triad not include as a component contributing to venous thrombosis?

    <p>Elevated D-dimers</p> Signup and view all the answers

    What is a common risk factor for developing deep vein thrombosis (DVT)?

    <p>Long-distance travel</p> Signup and view all the answers

    Which of the following is a common sign of pulmonary embolism (PE)?

    <p>Chest pain during deep breathing</p> Signup and view all the answers

    What percentage of patients experience post-thrombotic syndrome after deep vein thrombosis (DVT)?

    <p>40%</p> Signup and view all the answers

    What is the annual incidence of venous thrombosis?

    <p>1-3 cases per 1000 individuals</p> Signup and view all the answers

    What is a defining symptom of deep vein thrombosis (DVT)?

    <p>Pain in the leg</p> Signup and view all the answers

    Which factor is NOT a common cause of venous thrombosis?

    <p>Physical activity</p> Signup and view all the answers

    What is the risk of fatal pulmonary embolism (PE) following deep vein thrombosis (DVT)?

    <p>3%</p> Signup and view all the answers

    What does thrombophilia refer to in the context of venous thrombosis?

    <p>Increased long-term risk of venous thromboembolism</p> Signup and view all the answers

    What is the primary inheritance pattern of Anti-thrombin III Deficiency?

    <p>Autosomal dominant disorder</p> Signup and view all the answers

    What is the prevalence of Protein C Deficiency in the population?

    <p>1 in 500</p> Signup and view all the answers

    Which deficiency is characterized by an increased risk of venous thrombosis by 10-15 times?

    <p>Protein C Deficiency</p> Signup and view all the answers

    How many types of Protein S Deficiency exist?

    <p>3 types</p> Signup and view all the answers

    What is the estimated risk of developing a clot for individuals with Anti-thrombin III Deficiency?

    <p>50%</p> Signup and view all the answers

    Which factor demonstrates the highest increased risk for venous thrombosis in homozygotes?

    <p>Factor V Leiden</p> Signup and view all the answers

    What is one potential outcome of dysfunctional fibrinogen in Dysfibrinogenemia?

    <p>Hemorrhage in 50% of cases</p> Signup and view all the answers

    In which demographic are protein S levels generally higher?

    <p>Adult males</p> Signup and view all the answers

    What condition is associated with compression of the left common iliac vein?

    <p>Congenital anatomic variation</p> Signup and view all the answers

    How does age contribute to acquired thrombophilia?

    <p>Stasis in the venous system</p> Signup and view all the answers

    Which acquired risk factor increases the likelihood of thrombosis fourfold?

    <p>Malignancy</p> Signup and view all the answers

    Which Medications are known to associate with increased risk of acquired thrombophilia?

    <p>Oral contraceptives</p> Signup and view all the answers

    What is the frequency of the Prothrombin G20210A allele in the population?

    <p>1 in 50</p> Signup and view all the answers

    What role does activated protein C play in the clotting process?

    <p>Cleaves FV or FVIII</p> Signup and view all the answers

    Which clotting factors are increased by estrogen therapy?

    <p>Factors II, VII, VIII, IX, and X</p> Signup and view all the answers

    What effect does estrogen therapy have on anti-thrombin III levels?

    <p>Decreases levels</p> Signup and view all the answers

    In which scenarios do protein S levels notably decrease?

    <p>In pregnancy and hormone replacement therapy</p> Signup and view all the answers

    What are common effects caused by Antiphospholipid Antibody Syndrome in vivo?

    <p>Increased arterial and venous thrombosis</p> Signup and view all the answers

    What condition is characterized by a raised platelet count above 150-400 x 10^9/L?

    <p>Essential Thrombocytosis</p> Signup and view all the answers

    Which of the following is a characteristic of Polycythemia Rubra Vera?

    <p>Excess production of red blood cells</p> Signup and view all the answers

    What is a potential consequence of blood thickening in Polycythemia Rubra Vera?

    <p>Increased risk of thrombosis</p> Signup and view all the answers

    Why might urine appear darker in the morning in individuals with Paroxysmal Nocturnal Hemoglobinuria?

    <p>Urine concentration due to overnight lysis of RBCs</p> Signup and view all the answers

    Which of the following is NOT associated with Antiphospholipid Antibody Syndrome?

    <p>Increased hemoglobin levels</p> Signup and view all the answers

    Which type of disorder is Essential Thrombocytosis classified as?

    <p>Myeloproliferative neoplasms</p> Signup and view all the answers

    What is the first step that occurs in the normal haemostasis process following blood vessel injury?

    <p>Collagen exposed</p> Signup and view all the answers

    What mechanism facilitates the trapping of cells to form a stable thrombus?

    <p>Coagulation</p> Signup and view all the answers

    Which of the following is NOT a symptom associated with myocardial infarction (MI)?

    <p>Sudden weakness or numbness of the face</p> Signup and view all the answers

    What condition is primarily associated with the inappropriate activation of platelets in arterial thrombosis?

    <p>Atherosclerosis</p> Signup and view all the answers

    What is a common symptom of peripheral arterial disease (PAD)?

    <p>Pain in the legs during physical activity</p> Signup and view all the answers

    Which of the following best outlines the pathological consequences of venous thrombosis?

    <p>Deep Vein Thrombosis and Pulmonary Embolism</p> Signup and view all the answers

    What symptom is commonly found in ischaemic stroke due to arterial thrombosis?

    <p>Facial drooping on one side</p> Signup and view all the answers

    What could likely occur as a consequence of arterial thrombosis?

    <p>Reduction in blood supply to limbs</p> Signup and view all the answers

    What effect does estrogen therapy have on tissue plasminogen activator (tPA) levels?

    <p>Decreases tPA levels</p> Signup and view all the answers

    What is the percentage of the healthy population that has antiphospholipid antibodies?

    <p>5%</p> Signup and view all the answers

    Which condition is associated with increased arterial and venous thrombosis in vivo?

    <p>Antiphospholipid Antibody Syndrome</p> Signup and view all the answers

    In which condition do protein S levels decrease?

    <p>Pregnancy</p> Signup and view all the answers

    What characterizes Paroxysmal Nocturnal Hemoglobinuria (PNH)?

    <p>Lysis of red blood cells causing hemoglobinuria</p> Signup and view all the answers

    What is the main underlying defect in Paroxysmal Nocturnal Hemoglobinuria?

    <p>Defect in forming GPI-anchors</p> Signup and view all the answers

    Which of the following is NOT a type of myeloproliferative neoplasm?

    <p>Aplastic Anemia</p> Signup and view all the answers

    Which acquired risk factor is associated with an increased likelihood of thrombosis?

    <p>Hormone replacement therapy</p> Signup and view all the answers

    What percentage of young myocardial infarction (MI) patients have antiphospholipid antibodies?

    <p>21%</p> Signup and view all the answers

    What type of deficiency is Anti-thrombin III Deficiency classified as?

    <p>Both quantitative and qualitative deficiency</p> Signup and view all the answers

    What is the estimated lifetime risk of developing a clot for individuals with Anti-thrombin III Deficiency?

    <p>50%</p> Signup and view all the answers

    What is the prevalence of Protein C Deficiency in the general population?

    <p>1 in 500</p> Signup and view all the answers

    How many types of Protein S Deficiency exist?

    <p>3 types</p> Signup and view all the answers

    What inheritance pattern is associated with Factor V Leiden?

    <p>Autosomal dominant disorder</p> Signup and view all the answers

    What is the prevalence of Prothrombin G20210A allele in the population?

    <p>1 in 50</p> Signup and view all the answers

    What effect does the Prothrombin G20210A allele have on prothrombin levels?

    <p>Elevates prothrombin levels</p> Signup and view all the answers

    What is one of the major risk factors for acquired thrombophilia?

    <p>Age</p> Signup and view all the answers

    Which of the following is associated with an increased risk of venous thrombosis in individuals with Factor V Leiden?

    <p>3-5 times for heterozygotes</p> Signup and view all the answers

    What is the inheritance pattern of Dysfibrinogenemia?

    <p>Autosomal dominant disorder</p> Signup and view all the answers

    In which conditions do protein S levels typically drop?

    <p>During pregnancy and hormonal therapy</p> Signup and view all the answers

    Which congenital anatomic variation is associated with inherited thrombophilia?

    <p>Compression of the left common iliac vein</p> Signup and view all the answers

    What is the strongest risk factor for acquired thrombophilia?

    <p>Previous thrombosis</p> Signup and view all the answers

    What are some common signs of arterial thrombosis in myocardial infarction (MI)?

    <p>Pale skin and sweating</p> Signup and view all the answers

    Which diagnostic method is commonly used to confirm myocardial infarction?

    <p>Electrocardiogram (ECG) and serum markers</p> Signup and view all the answers

    What is a potential long-term consequence of deep vein thrombosis (DVT)?

    <p>Post-thrombotic syndrome</p> Signup and view all the answers

    Which treatment option is typically NOT associated with myocardial infarction?

    <p>Carotid endarterectomy</p> Signup and view all the answers

    What is the defining clinical tool used to assess symptoms of an ischemic stroke?

    <p>FAST (Face, Arm, Speech, Time)</p> Signup and view all the answers

    What characterizes the symptoms of deep vein thrombosis (DVT)?

    <p>Hot, red, swollen, painful leg</p> Signup and view all the answers

    What are the key components of Virchow's Triad in relation to venous thrombosis?

    <p>Endothelial damage, stasis, and hypercoagulability</p> Signup and view all the answers

    What is a major complication associated with venous thrombosis?

    <p>Pulmonary embolism (PE)</p> Signup and view all the answers

    Which symptom is indicative of pulmonary embolism (PE)?

    <p>Shortness of breath and chest pain</p> Signup and view all the answers

    What is the estimated incidence of venous thrombosis on an annual basis?

    <p>1-3 cases per 1000 individuals</p> Signup and view all the answers

    What is the prognosis for a patient after their first myocardial infarction?

    <p>13% die during hospital admission</p> Signup and view all the answers

    What immediate symptom is often present in an ischemic stroke?

    <p>Face asymmetries</p> Signup and view all the answers

    What is the primary treatment approach for deep vein thrombosis (DVT)?

    <p>Anticoagulation and thrombolytic therapy</p> Signup and view all the answers

    How is arterial thrombosis diagnosed in ischemic stroke?

    <p>By neuroimaging to differentiate types of stroke</p> Signup and view all the answers

    What underlying factor can lead to venous thrombosis in a patient?

    <p>Dehydration</p> Signup and view all the answers

    Study Notes

    Steps of Normal Haemostasis

    • Collagen is exposed upon blood vessel injury, initiating haemostasis.
    • Platelet adhesion occurs as platelets bind to exposed collagen.
    • Platelet activation follows, triggering a cascade of chemical signals.
    • Platelet secretion releases various substances that further attract and activate additional platelets.
    • Platelet aggregation happens as platelets clump together to form a primary plug.
    • Fibrin strands form through coagulation, stabilizing the clot by trapping cells.
    • This leads to the formation of a stable clot or thrombus.

    Physiological Processes of Blood Vessel Injury

    • Exposure of collagen activates platelets, leading to their adhesion, activation, secretion, and aggregation, followed by coagulation.

    Mechanism of Clot Stabilization

    • Coagulation results in the formation of fibrin strands that encapsulate and trap blood cells, solidifying the clot structure.

    Consequences of Arterial Thrombosis

    • Involves risks such as myocardial infarction (MI), ischemic stroke, and peripheral arterial disease (PAD), primarily due to atherosclerosis.

    Inappropriate Activation of Platelets

    • Arterial thrombosis triggered by inappropriate platelet activation due to:
      • Atherosclerosis in arteries.
      • Rupture of atherosclerotic plaques, releasing thrombogenic lipids.

    Symptoms of Ischemic Stroke

    • Sudden weakness or numbness in the face, arm, or leg, often unilateral.
    • Speech difficulties and confusion.
    • Vision problems in one or both eyes.

    Symptoms of Peripheral Arterial Disease (PAD)

    • Claudication: leg pain or cramping during activity.
    • Weakness or numbness in legs.
    • Non-healing sores on legs/feet and temperature variations.

    Symptoms of Myocardial Infarction (MI)

    • Central chest pain radiating to arms, back, neck, jaw, or stomach.
    • Accompanied by shortness of breath, sweating, nausea, and anxiety.

    Signs of Myocardial Infarction (MI)

    • Tachycardia, low-grade fever, pale clammy skin, changes in blood pressure, altered heart sounds.

    Diagnosis of Myocardial Infarction (MI)

    • Confirmed through ECG readings and elevated troponin and creatine kinase levels.

    Treatment Options for Myocardial Infarction (MI)

    • Thrombolytic therapy, anti-platelet medications, beta-blockers, percutaneous coronary intervention (PCTA), and coronary artery bypass grafting (CABG).

    Prognosis After First Myocardial Infarction (MI)

    • 23% may die before reaching the hospital.
    • 13% die during hospitalization.
    • 10% die within the first year post-discharge, with a continuous 5% risk annually thereafter.

    Ischemic Stroke Diagnosis

    • Based on clinical signs and symptoms, confirmed through neuroimaging (CT/MRI) to differentiate stroke types.

    Treatment Options for Ischemic Stroke

    • Thrombolytic therapy, anti-platelet therapies, and carotid endarterectomy.

    Prognosis After Ischemic Stroke

    • Complete recovery occurs in about 10% of cases.
    • Significant long-term deficits are common, with an increased risk of subsequent strokes. Hospital mortality is 20%.

    Causes of Venous Thrombosis

    • Risk factors include stasis (immobility), endothelial damage, and hypercoagulability contributing to Virchow's Triad.

    Symptoms of Venous Thrombosis

    • Pain and tenderness in affected leg.
    • Swelling, redness, and warmth, typically unilateral.

    Signs of Deep Vein Thrombosis (DVT)

    • Increased temperature, general malaise, elevated white blood cell count, and elevated erythrocyte sedimentation rate (ESR).

    Diagnosis of Deep Vein Thrombosis (DVT)

    • Confirmed via ultrasound, venogram, and elevated D-dimer levels.

    Treatment Options for Deep Vein Thrombosis (DVT)

    • Anti-coagulation therapy and thrombolytic treatment.

    Prevention Measures for Deep Vein Thrombosis (DVT)

    • Encouraging leg exercises, using support stockings, and prescribing prophylactic anti-coagulation.

    Prognosis of Deep Vein Thrombosis (DVT)

    • 3% risk of fatal pulmonary embolism (PE).

    Annual Incidence of Venous Thrombosis

    • Ranges from 1 to 3 cases per 1000 individuals.

    Major Complications of Venous Thrombosis

    • Associated with post-thrombotic syndrome in 40% of cases and a 3% mortality rate.

    Thrombophilia Overview

    • Refers to congenital or acquired conditions that increase the risk of venous thromboembolism.

    Congenital Thrombophilia Causes

    • Include deficiencies in antithrombin, protein C, protein S, Factor V Leiden, Prothrombin G20210A, and Dysfibrinogenemia.

    Acquired Thrombophilia Factors

    • Prior thrombosis, age, immobilization, surgery, malignancy, and hormonal therapies increase thrombotic risk.

    General Impact of Hormone Therapy

    • Estrogen can increase clotting factor levels while decreasing levels of anti-thrombin III and protein S, heightening thrombosis risk.

    Antiphospholipid Antibody Syndrome

    • Involves autoantibodies leading to increased risk of both arterial and venous thrombosis and associated with pregnancy complications.

    Essential Thrombocytosis (Thrombocythemia)

    • Characterized by elevated platelet counts, risk of thrombosis or bleeding, classified as a myeloproliferative neoplasm.

    Polycythemia Rubra Vera

    • Elevation of red blood cells leading to blood thickening, diagnosed by high hematocrit and hemoglobin levels.

    Paroxysmal Nocturnal Hemoglobinuria (PNH)

    • Condition leading to RBC lysis, hemoglobinuria, and risks of venous thrombosis and bone marrow failure.

    Summary of Thrombophilia Factors

    • Inherited thrombophilia syndromes (e.g., deficiencies in various coagulation factors) and acquired factors (e.g., past thrombosis, malignancy) contribute to thromboembolic risk.

    Steps of Normal Haemostasis

    • Collagen is exposed upon blood vessel injury, initiating haemostasis.
    • Platelet adhesion occurs as platelets bind to exposed collagen.
    • Platelet activation follows, triggering a cascade of chemical signals.
    • Platelet secretion releases various substances that further attract and activate additional platelets.
    • Platelet aggregation happens as platelets clump together to form a primary plug.
    • Fibrin strands form through coagulation, stabilizing the clot by trapping cells.
    • This leads to the formation of a stable clot or thrombus.

    Physiological Processes of Blood Vessel Injury

    • Exposure of collagen activates platelets, leading to their adhesion, activation, secretion, and aggregation, followed by coagulation.

    Mechanism of Clot Stabilization

    • Coagulation results in the formation of fibrin strands that encapsulate and trap blood cells, solidifying the clot structure.

    Consequences of Arterial Thrombosis

    • Involves risks such as myocardial infarction (MI), ischemic stroke, and peripheral arterial disease (PAD), primarily due to atherosclerosis.

    Inappropriate Activation of Platelets

    • Arterial thrombosis triggered by inappropriate platelet activation due to:
      • Atherosclerosis in arteries.
      • Rupture of atherosclerotic plaques, releasing thrombogenic lipids.

    Symptoms of Ischemic Stroke

    • Sudden weakness or numbness in the face, arm, or leg, often unilateral.
    • Speech difficulties and confusion.
    • Vision problems in one or both eyes.

    Symptoms of Peripheral Arterial Disease (PAD)

    • Claudication: leg pain or cramping during activity.
    • Weakness or numbness in legs.
    • Non-healing sores on legs/feet and temperature variations.

    Symptoms of Myocardial Infarction (MI)

    • Central chest pain radiating to arms, back, neck, jaw, or stomach.
    • Accompanied by shortness of breath, sweating, nausea, and anxiety.

    Signs of Myocardial Infarction (MI)

    • Tachycardia, low-grade fever, pale clammy skin, changes in blood pressure, altered heart sounds.

    Diagnosis of Myocardial Infarction (MI)

    • Confirmed through ECG readings and elevated troponin and creatine kinase levels.

    Treatment Options for Myocardial Infarction (MI)

    • Thrombolytic therapy, anti-platelet medications, beta-blockers, percutaneous coronary intervention (PCTA), and coronary artery bypass grafting (CABG).

    Prognosis After First Myocardial Infarction (MI)

    • 23% may die before reaching the hospital.
    • 13% die during hospitalization.
    • 10% die within the first year post-discharge, with a continuous 5% risk annually thereafter.

    Ischemic Stroke Diagnosis

    • Based on clinical signs and symptoms, confirmed through neuroimaging (CT/MRI) to differentiate stroke types.

    Treatment Options for Ischemic Stroke

    • Thrombolytic therapy, anti-platelet therapies, and carotid endarterectomy.

    Prognosis After Ischemic Stroke

    • Complete recovery occurs in about 10% of cases.
    • Significant long-term deficits are common, with an increased risk of subsequent strokes. Hospital mortality is 20%.

    Causes of Venous Thrombosis

    • Risk factors include stasis (immobility), endothelial damage, and hypercoagulability contributing to Virchow's Triad.

    Symptoms of Venous Thrombosis

    • Pain and tenderness in affected leg.
    • Swelling, redness, and warmth, typically unilateral.

    Signs of Deep Vein Thrombosis (DVT)

    • Increased temperature, general malaise, elevated white blood cell count, and elevated erythrocyte sedimentation rate (ESR).

    Diagnosis of Deep Vein Thrombosis (DVT)

    • Confirmed via ultrasound, venogram, and elevated D-dimer levels.

    Treatment Options for Deep Vein Thrombosis (DVT)

    • Anti-coagulation therapy and thrombolytic treatment.

    Prevention Measures for Deep Vein Thrombosis (DVT)

    • Encouraging leg exercises, using support stockings, and prescribing prophylactic anti-coagulation.

    Prognosis of Deep Vein Thrombosis (DVT)

    • 3% risk of fatal pulmonary embolism (PE).

    Annual Incidence of Venous Thrombosis

    • Ranges from 1 to 3 cases per 1000 individuals.

    Major Complications of Venous Thrombosis

    • Associated with post-thrombotic syndrome in 40% of cases and a 3% mortality rate.

    Thrombophilia Overview

    • Refers to congenital or acquired conditions that increase the risk of venous thromboembolism.

    Congenital Thrombophilia Causes

    • Include deficiencies in antithrombin, protein C, protein S, Factor V Leiden, Prothrombin G20210A, and Dysfibrinogenemia.

    Acquired Thrombophilia Factors

    • Prior thrombosis, age, immobilization, surgery, malignancy, and hormonal therapies increase thrombotic risk.

    General Impact of Hormone Therapy

    • Estrogen can increase clotting factor levels while decreasing levels of anti-thrombin III and protein S, heightening thrombosis risk.

    Antiphospholipid Antibody Syndrome

    • Involves autoantibodies leading to increased risk of both arterial and venous thrombosis and associated with pregnancy complications.

    Essential Thrombocytosis (Thrombocythemia)

    • Characterized by elevated platelet counts, risk of thrombosis or bleeding, classified as a myeloproliferative neoplasm.

    Polycythemia Rubra Vera

    • Elevation of red blood cells leading to blood thickening, diagnosed by high hematocrit and hemoglobin levels.

    Paroxysmal Nocturnal Hemoglobinuria (PNH)

    • Condition leading to RBC lysis, hemoglobinuria, and risks of venous thrombosis and bone marrow failure.

    Summary of Thrombophilia Factors

    • Inherited thrombophilia syndromes (e.g., deficiencies in various coagulation factors) and acquired factors (e.g., past thrombosis, malignancy) contribute to thromboembolic risk.

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    Description

    Test your knowledge on the steps involved in normal haemostasis following blood vessel injury. This quiz covers the physiological processes from collagen exposure to the formation of a stable clot. Understand how platelets adhere, activate, and aggregate in response to vascular injury.

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