2.1: Coagulation and Fibrinolytic Systems/Reagents and Methods

Which of the following initiates in vivo coagulation by activation of factor VII?

A. Protein C

B. Tissue factor (TF)

C. Plasmin activator

D. Thrombomodulin (TM)

Which of the following initiates in vivo coagulation by activation of factor VII?

A. Protein C

B. Tissue factor (TF)

C. Plasmin activator

D. Thrombomodulin (TM)

Which of the following clotting factors plays a role in clotvformation in vitro, but not in vivo?

A. Factor VIIa

B. Factor IIa

C. Factor XIIa

D. Factor Xa

Which of the following clotting factors plays a role in clotvformation in vitro, but not in vivo?

A. Factor VIIa

B. Factor IIa

C. Factor XIIa

D. Factor Xa

The anticoagulant of choice for most routine coagulation studies is:

A. Sodium oxalate

B. Sodium citrate

C. Heparin

D. Ethylenediaminetetraacetic acid (EDTA)

The anticoagulant of choice for most routine coagulation studies is:

A. Sodium oxalate

B. Sodium citrate

C. Heparin

D. Ethylenediaminetetraacetic acid (EDTA)

Which anticoagulant:blood ratio is correct for coagulation

procedures?

A. 1:4

B. 1:5

C. 1:9

D. 1:10

Which anticoagulant:blood ratio is correct for coagulation

procedures?

A. 1:4

B. 1:5

C. 1:9

D. 1:10

Which results would be expected for PT and APTT in a patient

with polycythemia?

A. Both prolonged

B. Both shortened

C. Normal PT, prolonged APTT

D. Both normal

Which results would be expected for PT and APTT in a patient

with polycythemia?

A. Both prolonged

B. Both shortened

C. Normal PT, prolonged APTT

D. Both normal

Which reagents are used in the PT test?

A. Thromboplastin and sodium chloride

B. Thromboplastin and potassium chloride

C. Thromboplastin and calcium

D. Actin and calcium chloride

Which reagents are used in the PT test?

A. Thromboplastin and sodium chloride

B. Thromboplastin and potassium chloride

C. Thromboplastin and calcium

D. Actin and calcium chloride

Which test would be abnormal in a patient with factor X

deficiency?

A. PT only

B. APTT only

C. PT and APTT

D. Thrombin time (TT)

Which test would be abnormal in a patient with factor X

deficiency?

A. PT only

B. APTT only

C. PT and APTT

D. Thrombin time (TT)

Which clotting factor is not measured by the PT and APTT

tests?

A. Factor VIII

B. Factor IX

C. Factor V D

D. Factor XIII

Which clotting factor is not measured by the PT and APTT tests?

A. Factor VIII

B. Factor IX

C. Factor V D

D. Factor XIII

A modification of which procedure can be used to measure

fibrinogen?

A. PT

B. APTT

C. TT

D. Fibrin degradation products

A modification of which procedure can be used to measure

fibrinogen?

A. PT

B. APTT

C. TT

D. Fibrin degradation products

Which of the following characterizes vitamin K?

A. It is required for biological activity of fibrinolysis

B. Its activity is enhanced by heparin therapy

C. It is required for carboxylation of glutamate residues

of some coagulation factors

D. It is made by endothelial cells

Which of the following characterizes vitamin K?

A. It is required for biological activity of fibrinolysis

B. Its activity is enhanced by heparin therapy

C. It is required for carboxylation of glutamate residues

of some coagulation factors

D. It is made by endothelial cells

Which fragments of fibrin clot degradation are measured by

the D-dimer test?

A. Fragments X and Y

B. Fibrinopeptide A and B

C. Fragments D and E

D. The D-D domains

Which fragments of fibrin clot degradation are measured by

the D-dimer test?

A. Fragments X and Y

B. Fibrinopeptide A and B

C. Fragments D and E

D. The D-D domains

Which of the following clotting factors are measured by the

APTT test?

A. Factors II, VII, IX, X

B. Factors VII, X, V, II, I

C. Factors XII, XI, IX, VIII, X, V, II, I

D. Factors XII, VII, X, V, II, I

Which of the following clotting factors are measured by the

APTT test?

A. Factors II, VII, IX, X

B. Factors VII, X, V, II, I

C. Factors XII, XI, IX, VIII, X, V, II, I

D. Factors XII, VII, X, V, II, I

Which coagulation test(s) would be abnormal in a patient with vitamin K deficiency?

A. PT only

B. PT and APTT

C. Fibrinogen level

D. TT

Which coagulation test(s) would be abnormal in a patient with vitamin K deficiency?

A. PT only

B. PT and APTT

C. Fibrinogen level

D. TT

Which of the following is correct regarding the international normalized ratio (INR)?

A. It uses the international sensitivity ratio (ISR)

B. It standardizes PT results

C. It standardizes APTT results

D. It is used to monitor heparin therapy

Which of the following is correct regarding the international normalized ratio (INR)?

A. It uses the international sensitivity ratio (ISR)

B. It standardizes PT results

C. It standardizes APTT results

D. It is used to monitor heparin therapy

Which of the following is referred to as an endogenous activator of plasminogen?

A. Streptokinase

B. Transamidase

C. Tissue plasminogen activator (tPA)

D. tPA inhibitor

Which of the following is referred to as an endogenous activator of plasminogen?

A. Streptokinase

B. Transamidase

C. Tissue plasminogen activator (tPA)

D. tPA inhibitor

Which protein is the primary inhibitor of the fibrinolytic system?

A. Protein C

B. Protein S

C. α2-Antiplasmin

D. α2-Macroglobulin

Which protein is the primary inhibitor of the fibrinolytic system?

A. Protein C

B. Protein S

C. α2-Antiplasmin

D. α2-Macroglobulin

Which of the following statements is correct regarding the D-dimer test?

A. Levels are decreased in DIC

B. Test detects polypeptides A and B

C. Test detects fragments D and E

D. Test has a negative predictive value

Which of the following statements is correct regarding the D-dimer test?

A. Levels are decreased in DIC

B. Test detects polypeptides A and B

C. Test detects fragments D and E

D. Test has a negative predictive value

A protein that plays a role in both coagulation and PLT aggregation is:

A. Factor I

B. Factor VIII

C. Factor IX

D. Factor XI

A protein that plays a role in both coagulation and PLT aggregation is:

A. Factor I

B. Factor VIII

C. Factor IX

D. Factor XI

A standard 4.5-mL blue-top tube filled with 3.0 mL of blood was submitted to the laboratory for PT and APTT tests. The sample is from a patient undergoing surgery the following
morning for a tonsillectomy. Which of the following is the necessary course of action by the medical laboratory
scientist?

A. Run both tests in duplicate and report the average result

B. Reject the sample and request a new sample

C. Report the PT result

D. Report the APTT result

A standard 4.5-mL blue-top tube filled with 3.0 mL of blood was submitted to the laboratory for PT and APTT tests. The sample is from a patient undergoing surgery the following
morning for a tonsillectomy. Which of the following is the necessary course of action by the medical laboratory
scientist?

A. Run both tests in duplicate and report the average result

B. Reject the sample and request a new sample

C. Report the PT result

D. Report the APTT result

Which statement is correct regarding sample storage for the PT test?

A. Stable for 24 hours if the sample is capped

B. Stable for 24 hours if the sample is refrigerated at 4°C

C. Stable for 4 hours if the sample is stored at 4°C

D. Should be run within 8 hours

Which statement is correct regarding sample storage for the PT test?

A. Stable for 24 hours if the sample is capped

B. Stable for 24 hours if the sample is refrigerated at 4°C

C. Stable for 4 hours if the sample is stored at 4°C

D. Should be run within 8 hours

In primary fibrinolysis, the fibrinolytic activity results in response to:

A. Increased fibrin formation

B. Spontaneous activation of fibrinolysis

C. Increased fibrin monomers

D. DIC

In primary fibrinolysis, the fibrinolytic activity results in response to:

A. Increased fibrin formation

B. Spontaneous activation of fibrinolysis

C. Increased fibrin monomers

D. DIC

Plasminogen deficiency is associated with:

A. Bleeding

B. Thrombosis

C. Increased fibrinolysis

D. Increased coagulation

Plasminogen deficiency is associated with:

A. Bleeding

B. Thrombosis

C. Increased fibrinolysis

D. Increased coagulation

Which of the following clotting factors are activated by thrombin that is generated by tissue pathway (TF-VIIa)?

A. Factors XII, XI

B. Factors XII, I

C. Factors I, II

D. Factors V, VIII

Which of the following clotting factors are activated by thrombin that is generated by tissue pathway (TF-VIIa)?

A. Factors XII, XI

B. Factors XII, I

C. Factors I, II

D. Factors V, VIII

Which substrate is used in a chromogenic factor assay?

A. p-nitroaniline (pNa)

B. Chlorophenol red

C. Prussian blue

D. Ferricyanide

Which substrate is used in a chromogenic factor assay?

A. p-nitroaniline (pNa)

B. Chlorophenol red

C. Prussian blue

D. Ferricyanide

Which of the following antibodies is used in the D-dimer assay?

A. Polyclonal antibody directed against X and Y fragments

B. Polyclonal antibody directed against D-dimer

C. Monoclonal antibody against D and E fragments

D. Monoclonal antibody against D-dimer

Which of the following antibodies is used in the D-dimer assay?

A. Polyclonal antibody directed against X and Y fragments

B. Polyclonal antibody directed against D-dimer

C. Monoclonal antibody against D and E fragments

D. Monoclonal antibody against D-dimer