Coagulation Medical Review 2023 Questions and Answers
Verified
Which of the following initiates in vivo coagulation by activating factor VII?
Tissue factor
Which of the following clotting factors plays a role in clot formation in vitro, but not in
vivo? (In vitro clot formation and not in in coagulation)
XIIa
The anticoagulant of choice for most routine coagulation studies is _____________.
Sodium Citrate
Which ratio of anticoagulant-to-blood is correct for coagulation procedures?
1:9
Which result would be expected for the prothrombin time (PT) and activated partial
thromboplastin time (PTT) in a patient with polycythemia?
Both prolonged
What reagents are used in the PT test?
Thromboplastin and calcium
Which test would be abnormal in a patient with factor X deficiency?
PT and PTT time
Which clotting factor is not measured by PT and PTT tests?
Factor XIII
A modification of which procedure can be used to measure fibrinogen?
Thrombin time
Which of the following characterizes vitamin K?
It is required for carboxylation of glutamate residue of some coagulation factors
Which statement about the fibrinogen/fibrin degradation product test is correct?
It detects late degradation products (D and E)
Which of the following clotting factors are measured by the PPT test?
XII, XI, IX, VIII, X, V, II, I
Which coagulation test(s) would be abnormal in a vitamin K-deficient patient?
PT and PTT
Which of the following is correct regarding the international normalized ratio (INR)?
It standardizes PT results
Which of the following is referred to as an endogenous activator of plasminogen?
Tissue plasminogen activator
Which protein is the primary inhibitor of the fibrinolytic system?
Alpha2-Antiplasmin
Which of the following statements is correct regarding the D-dimer test?
Test has a negative predictive value
A protein that plays a role in both coagulation and platelet aggregation is
____________.
Factor I
A standard 4.5mL blue-top tube filled with 3.0mL of blood was submitted to the
laboratory for PT and PTT tests. The sample is from a patient undergoing surgery the
, following morning for a tonsillectomy. Which of the following is the appropriate course of
action by the technologist?
Reject the sample and request a new sample
Which statement is correct regarding sample storage for the prothrombin time test?
Stable for 24 hours if the sample is capped
In primary fibrinolysis, the fibrinolytic activity results in response to ___________.
Spontaneous activity of fibirnolysis
Plasminogen deficiency is associated with ______________.
Thrombosis
Which of the following clotting factors are activated by thrombin that is generated by
tissue pathway (TF-VIIa)?
V, VIII
What substrate is used in a chromogenic factor assay?
p-nitroanaline
Which of the following antibodies is used in the D-dimer assay?
Monoclonal against D-dimer
Thrombotic thrombocytopenia purpura (TTP) is characterized by ____________.
Increased platelet aggregation
Thrombocytopenia may be associated with _____________.
Hypersplenism
Aspirin prevents platelet aggregation by inhibiting the action of which enzyme?
Cyclo-oxygenase
Normal platelet adhesion depends upon ____________.
Glycoprotein Ib
Which of the following test results is normal in a patient with classic von Willebrand's
disease?
Platelet count
Bernard-Soulier syndrome is associated with ___________.
Thrombocytopenia and giant platelets
When performing platelet aggregation studies, which set of platelet aggregation results
would be the most likely to be associated with Bernard-Soulier syndrome?
Normal platelet aggregation to collagen, ADP, and epinephrine, decreased aggregation
to ristocetin
Which set of platelet responses would be most likely associated with Glanzmann's
thrombasthenia?
Normal platelet aggregation to ristocetin; decreased aggregation to collagen, ADP, and
epinephrine
Which of the following is a characteristic of acute immune thrombocytopenic purpura?
Spontaneous remission within a few weeks
TTP differes from DIC in that ___________.
PTT is normal in TTP but prolonged in DIC
Several hours after birth, a baby boy develops petechiae and purpura and a
hemorrhagic diathesis. The platelet count is 18x10^9/L. What is the most likely
explanation for the low platelet count?
Neonatal alloimmune thrombocytopenia
Which of the following is associated with post-transfusion purpura (PTP)?
Verified
Which of the following initiates in vivo coagulation by activating factor VII?
Tissue factor
Which of the following clotting factors plays a role in clot formation in vitro, but not in
vivo? (In vitro clot formation and not in in coagulation)
XIIa
The anticoagulant of choice for most routine coagulation studies is _____________.
Sodium Citrate
Which ratio of anticoagulant-to-blood is correct for coagulation procedures?
1:9
Which result would be expected for the prothrombin time (PT) and activated partial
thromboplastin time (PTT) in a patient with polycythemia?
Both prolonged
What reagents are used in the PT test?
Thromboplastin and calcium
Which test would be abnormal in a patient with factor X deficiency?
PT and PTT time
Which clotting factor is not measured by PT and PTT tests?
Factor XIII
A modification of which procedure can be used to measure fibrinogen?
Thrombin time
Which of the following characterizes vitamin K?
It is required for carboxylation of glutamate residue of some coagulation factors
Which statement about the fibrinogen/fibrin degradation product test is correct?
It detects late degradation products (D and E)
Which of the following clotting factors are measured by the PPT test?
XII, XI, IX, VIII, X, V, II, I
Which coagulation test(s) would be abnormal in a vitamin K-deficient patient?
PT and PTT
Which of the following is correct regarding the international normalized ratio (INR)?
It standardizes PT results
Which of the following is referred to as an endogenous activator of plasminogen?
Tissue plasminogen activator
Which protein is the primary inhibitor of the fibrinolytic system?
Alpha2-Antiplasmin
Which of the following statements is correct regarding the D-dimer test?
Test has a negative predictive value
A protein that plays a role in both coagulation and platelet aggregation is
____________.
Factor I
A standard 4.5mL blue-top tube filled with 3.0mL of blood was submitted to the
laboratory for PT and PTT tests. The sample is from a patient undergoing surgery the
, following morning for a tonsillectomy. Which of the following is the appropriate course of
action by the technologist?
Reject the sample and request a new sample
Which statement is correct regarding sample storage for the prothrombin time test?
Stable for 24 hours if the sample is capped
In primary fibrinolysis, the fibrinolytic activity results in response to ___________.
Spontaneous activity of fibirnolysis
Plasminogen deficiency is associated with ______________.
Thrombosis
Which of the following clotting factors are activated by thrombin that is generated by
tissue pathway (TF-VIIa)?
V, VIII
What substrate is used in a chromogenic factor assay?
p-nitroanaline
Which of the following antibodies is used in the D-dimer assay?
Monoclonal against D-dimer
Thrombotic thrombocytopenia purpura (TTP) is characterized by ____________.
Increased platelet aggregation
Thrombocytopenia may be associated with _____________.
Hypersplenism
Aspirin prevents platelet aggregation by inhibiting the action of which enzyme?
Cyclo-oxygenase
Normal platelet adhesion depends upon ____________.
Glycoprotein Ib
Which of the following test results is normal in a patient with classic von Willebrand's
disease?
Platelet count
Bernard-Soulier syndrome is associated with ___________.
Thrombocytopenia and giant platelets
When performing platelet aggregation studies, which set of platelet aggregation results
would be the most likely to be associated with Bernard-Soulier syndrome?
Normal platelet aggregation to collagen, ADP, and epinephrine, decreased aggregation
to ristocetin
Which set of platelet responses would be most likely associated with Glanzmann's
thrombasthenia?
Normal platelet aggregation to ristocetin; decreased aggregation to collagen, ADP, and
epinephrine
Which of the following is a characteristic of acute immune thrombocytopenic purpura?
Spontaneous remission within a few weeks
TTP differes from DIC in that ___________.
PTT is normal in TTP but prolonged in DIC
Several hours after birth, a baby boy develops petechiae and purpura and a
hemorrhagic diathesis. The platelet count is 18x10^9/L. What is the most likely
explanation for the low platelet count?
Neonatal alloimmune thrombocytopenia
Which of the following is associated with post-transfusion purpura (PTP)?
