Question 1

Which unusual laboratory finding may be present in sepsis-induced DIC?

Accepted Answer

A) Fibrinogen may be high because it is an acute phase reactant. 
B) Schistocytes are absent because the fever destroys them. 
C) D dimer is low because the toxins prevent fibrin lysis. 
D) The PT and PTT are low because bacteria interfere with these tests. 
A) Fibrinogen may be high because it is an acute phase reactant. 
B) Schistocytes are absent because the fever destroys them. 
C) D dimer is low because the toxins prevent fibrin lysis. 
D) The PT and PTT are low because bacteria interfere with these tests. A

Question 2

Why does the factor V Leiden mutation increase thrombotic risk?

Accepted Answer

A) makes factor Va resistant to degradation by activated protein C 
B) makes blood more viscous 
C) makes factor V more susceptible to activation by thrombin 
D) decreases the binding of factor Va to the inhibitor antithrombin 
A) makes factor Va resistant to degradation by activated protein C 
B) makes blood more viscous 
C) makes factor V more susceptible to activation by thrombin 
D) decreases the binding of factor Va to the inhibitor antithrombin A

Question 3

A 37-year-old female patient has a PTT of 76 seconds (reference range,25 to 37 seconds).Her plasma is mixed 1:1 with normal plasma.An immediate PTT performed on the mix is 74 seconds.Which of the following is the most likely diagnosis?

Accepted Answer

A) hemophilia A 
B) factor VIII inhibitor 
C) intrinsic factor deficiency 
D) lupus anticoagulant 
A) hemophilia A 
B) factor VIII inhibitor 
C) intrinsic factor deficiency 
D) lupus anticoagulant D

Question 4

What is the best method to prevent warfarin-induced skin necrosis during treatment for thrombosis?

Accepted Answer

A) Use higher dose of warfarin early in treatment. 
B) Give the patient injections of protein C. 
C) Stop warfarin at the first sign of necrosis. 
D) Use heparin for first 5 days in conjunction with warfarin. 
A) Use higher dose of warfarin early in treatment. 
B) Give the patient injections of protein C. 
C) Stop warfarin at the first sign of necrosis. 
D) Use heparin for first 5 days in conjunction with warfarin.

Question 5

A patient arrives at the emergency department complaining of pain in the calf of his left leg and shortness of breath.A "stat" D dimer is ordered.Why is this useful information for this patient's care?

Accepted Answer

A) An elevated D dimer supports the possibility of deep vein thrombosis. 
B) An elevated D dimer is diagnostic for deep vein thrombosis. 
C) A normal D dimer is diagnostic for deep vein thrombosis. 
D) This was not an appropriate test to order on this patient. 
A) An elevated D dimer supports the possibility of deep vein thrombosis. 
B) An elevated D dimer is diagnostic for deep vein thrombosis. 
C) A normal D dimer is diagnostic for deep vein thrombosis. 
D) This was not an appropriate test to order on this patient.

Question 6

Which of the following is the cause for most strokes and heart attacks in the United States?

Accepted Answer

A) hemorrhage 
B) thrombocytopenia 
C) cancer 
D) consequences of thrombotic events 
A) hemorrhage 
B) thrombocytopenia 
C) cancer 
D) consequences of thrombotic events

Question 7

What substance is used to activate protein C in the chromogenic assay to determine its concentration?

Accepted Answer

A) partial thromboplastin 
B) a specific snake venom 
C) kaolin 
D) heparin 
A) partial thromboplastin 
B) a specific snake venom 
C) kaolin 
D) heparin

Question 8

What tests should be performed on a regular basis on patients receiving therapeutic heparin?

Accepted Answer

A) PT and hematocrit 
B) PTT and white count 
C) PTT and platelet count 
D) factor assays and platelet count 
A) PT and hematocrit 
B) PTT and white count 
C) PTT and platelet count 
D) factor assays and platelet count

Question 9

A thrombosis risk testing profile is ordered on a patient being treated with warfarin for a blood clot in the leg.Select the best course of action.

Accepted Answer

A) Run the tests immediately. 
B) Reject the order. 
C) Perform only the tests for protein C and protein S. 
D) Recommend the testing be postponed until the warfarin is discontinued. 
A) Run the tests immediately. 
B) Reject the order. 
C) Perform only the tests for protein C and protein S. 
D) Recommend the testing be postponed until the warfarin is discontinued.

Question 10

Why does prothrombin G20210A increase the risk of thrombosis?

Accepted Answer

A) makes prothrombin activation easier 
B) elevates prothrombin levels 
C) decreases binding of thrombin by antithrombin 
D) decreases binding of plasminogen to prothrombin 
A) makes prothrombin activation easier 
B) elevates prothrombin levels 
C) decreases binding of thrombin by antithrombin 
D) decreases binding of plasminogen to prothrombin

Question 11

A patient has a quantitative D dimer of 800 ng/mL.Which can be ruled out from the following list?

Accepted Answer

A) DIC 
B) deep vein thrombosis 
C) pulmonary embolus 
D) patient is normal 
A) DIC 
B) deep vein thrombosis 
C) pulmonary embolus 
D) patient is normal

Question 12

When the chromogenic assay for antithrombin is performed,which of the following is true?

Accepted Answer

A) The colored end-product intensity is inversely proportional to the antithrombin concentration. 
B) The chromogenic substrate is bound by antithrombin. 
C) Warfarin is added to the patient sample before testing to improve sensitivity. 
D) Activated protein C competes for the chromogenic substrate, so it must first be selectively removed. 
A) The colored end-product intensity is inversely proportional to the antithrombin concentration. 
B) The chromogenic substrate is bound by antithrombin. 
C) Warfarin is added to the patient sample before testing to improve sensitivity. 
D) Activated protein C competes for the chromogenic substrate, so it must first be selectively removed.

Question 13

Which of the following is used to treat DIC?

Accepted Answer

A) antithrombin and protein C concentrates 
B) platelet transfusions and fresh frozen plasma (FFP) 
C) heparin 
D) all of the above 
A) antithrombin and protein C concentrates 
B) platelet transfusions and fresh frozen plasma (FFP) 
C) heparin 
D) all of the above

Question 14

All of the following are associated with an increased risk of thrombosis except

Accepted Answer

A) high high-density lipoprotein (HDL) cholesterol 
B) increased homocysteine 
C) immobilization of extremities 
D) increased high-sensitivity C-reactive protein 
A) high high-density lipoprotein (HDL) cholesterol 
B) increased homocysteine 
C) immobilization of extremities 
D) increased high-sensitivity C-reactive protein

Question 15

Which of the following results puts the patient at an increased risk for thrombosis?

Accepted Answer

A) total cholesterol of 180 mg/dL 
B) PTT of 25 seconds 
C) deficiency of factor V 
D) chronically elevated fibrinogen 
A) total cholesterol of 180 mg/dL 
B) PTT of 25 seconds 
C) deficiency of factor V 
D) chronically elevated fibrinogen

Question 16

Which of the following is an expected finding in DIC?

Accepted Answer

A) elevated D-dimer and fibrin split products 
B) high platelet count 
C) low prothrombin time (PT) and PTT 
D) low TT 
A) elevated D-dimer and fibrin split products 
B) high platelet count 
C) low prothrombin time (PT) and PTT 
D) low TT

Question 17

What is important about the test systems used for detection of the lupus anticoagulant?

Accepted Answer

A) The phospholipid concentration should be high. 
B) Ellagic acid should be the PTT activator substance. 
C) The patient plasma and normal plasma used for mixing studies should be platelet poor. 
D) A 1:1 mix should be performed when the initial test is normal to improve the sensitivity. 
A) The phospholipid concentration should be high. 
B) Ellagic acid should be the PTT activator substance. 
C) The patient plasma and normal plasma used for mixing studies should be platelet poor. 
D) A 1:1 mix should be performed when the initial test is normal to improve the sensitivity.

Question 18

A patient who is not on heparin and has no history of a factor deficiency has a prolonged partial thromboplastin time (PTT).Select the test that should be performed next.

Accepted Answer

A) high-sensitivity C-reactive protein 
B) mixing studies for lupus anticoagulant 
C) thrombin time (TT) 
D) lipid panel 
A) high-sensitivity C-reactive protein 
B) mixing studies for lupus anticoagulant 
C) thrombin time (TT) 
D) lipid panel

Question 19

Which of the following makes a patient more prone to hemorrhage?

Accepted Answer

A) protein C deficiency 
B) acute disseminated intravascular coagulation (DI
C)  
C) factor V Leiden 
D) free protein S deficiency 
A) protein C deficiency 
B) acute disseminated intravascular coagulation (DI
C)  
C) factor V Leiden 
D) free protein S deficiency

Question 20

Inappropriate formation of platelets or fibrin clots that obstructs blood vessels is called

Accepted Answer

A) thrombophilia. 
B) thrombosis. 
C) embolus. 
D) factor V Leiden. 
A) thrombophilia. 
B) thrombosis. 
C) embolus. 
D) factor V Leiden.

Exam 39: Thrombotic Disorders and Laboratory Assessment

Which unusual laboratory finding may be present in sepsis-induced DIC?

Why does the factor V Leiden mutation increase thrombotic risk?

A 37-year-old female patient has a PTT of 76 seconds (reference range,25 to 37 seconds).Her plasma is mixed 1:1 with normal plasma.An immediate PTT performed on the mix is 74 seconds.Which of the following is the most likely diagnosis?

What is the best method to prevent warfarin-induced skin necrosis during treatment for thrombosis?

A patient arrives at the emergency department complaining of pain in the calf of his left leg and shortness of breath.A "stat" D dimer is ordered.Why is this useful information for this patient's care?

Which of the following is the cause for most strokes and heart attacks in the United States?

What substance is used to activate protein C in the chromogenic assay to determine its concentration?

What tests should be performed on a regular basis on patients receiving therapeutic heparin?

A thrombosis risk testing profile is ordered on a patient being treated with warfarin for a blood clot in the leg.Select the best course of action.

Why does prothrombin G20210A increase the risk of thrombosis?

A patient has a quantitative D dimer of 800 ng/mL.Which can be ruled out from the following list?

When the chromogenic assay for antithrombin is performed,which of the following is true?

Which of the following is used to treat DIC?

All of the following are associated with an increased risk of thrombosis except

Which of the following results puts the patient at an increased risk for thrombosis?

Which of the following is an expected finding in DIC?

What is important about the test systems used for detection of the lupus anticoagulant?

A patient who is not on heparin and has no history of a factor deficiency has a prolonged partial thromboplastin time (PTT).Select the test that should be performed next.

Which of the following makes a patient more prone to hemorrhage?

Inappropriate formation of platelets or fibrin clots that obstructs blood vessels is called

An Overview of Clinical Laboratory Hematology

Safety in the Hematology Laboratory

Blood Specimen Collection

Care and Use of the Microscope

Quality Assurance in Hematology and Hemostasis Testing

Cellular Structure and Function

Hematopoiesis

Erythrocyte Production and Destruction

Erythrocyte Metabolism and Membrane Structure and Function

Hemoglobin Metabolism

Iron Kinetics and Laboratory Assessment

Leukocyte Development, Kinetics, and Functions

Platelet Production, Structure, and Function

Manual, Semiautomated and Point-of-Care Testing in Hematology

Automated Blood Cell Analysis

Examination of the Peripheral Blood Film and Correlation with the Complete Blood Count

Bone Marrow Examination

Body Fluid Analysis in the Hematology Laboratory

Anemias: Red Blood Cell Morphology and Approach to Diagnosis

Disorders of Iron Kinetics and Heme Metabolism

Anemias Caused by Defects of DNA Metabolism

Bone Marrow Failure

Introduction to Increased Destruction of Erythrocytes

Intrinsic Defects Leading to Increased Erythrocyte Destruction

Extrinsic Defects Leading to Increased Erythrocyte Destruction Nonimmune Causes

Extrinsic Defects Leading to Increased Erythrocyte Destruction Immune Causes

Hemoglobinopathies (Structural Defects in Hemoglobin)

Thalassemias

Nonmalignant Leukocyte Disorders

Cytogenetics

Molecular Diagnostics in Hematopathology

Flow Cytometric Analysis in Hematologic Disorders

Myeloproliferative Neoplasms

Myelodysplastic Syndromes

Acute Leukemias

Mature Lymphoid Neoplasms

Normal Hemostasis and Coagulation

Hemorrhagic Disorders and Laboratory Assessment

Thrombocytopenia and Thrombocytosis

Qualitative Disorders of Platelets and Vasculature

Laboratory Evaluation of Hemostasis

Antithrombotic Therapies and their Laboratory Assessment

Hemostasis and Coagulation Instrumentation

Pediatric and Geriatric Hematology and Hemostasis

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