2.3 Coagulation System Disorders

Question 1

The APTT is sensitive to a deficiency of which clotting factor?

Answer 1

Factor X

Question 2

Which test result would be normal in a patient with dysfibrinogenemia?

A. TT
B. APTT
C. PT
D. Immunologic fibrinogen level

Answer 2

Immunologic fibrinogen level

Question 3

A patient with a prolonged PT is given intravenous vitamin K. PT is corrected to normal after 24 hours. Which clinical condition most likely caused these results?

Answer 3

Obstructive jaundice

Question 4

Which factor deficiency is associated with prolonged PT and APTT?

Answer 4

Factor X

Question 5

Prolonged APTT is corrected with factor VIII–deficient plasma but not with factor IX deficient plasma. Which factor is deficient?

Answer 5

Factor IX

Question 6

Which of the following is a characteristic of classic hemophilia A?

Answer 6

Mild to severe bleeding episodes

Question 7

Refer to the following results:

PT = prolonged
APTT = prolonged
PLT count = decreased

Which disorder may be indicated?

Answer 7

DIC

Question 8

Which of the following is a predisposing condition for the development of DIC?

Answer 8

Adenocarcinoma

Question 9

Factor XII deficiency is associated with:

Answer 9

Increased risk of thrombosis

Question 10

The following results were obtained on a patient: normal PLT count and function, normal PT, and prolonged APTT. Which of the following disorders is most consistent with these results?

Answer 10

Hemophilia A

Question 11

The following laboratory results were obtained from a 40-year-old woman: PT = 20 sec; APTT = 50 sec; TT = 18 sec. What is the most probable diagnosis?

Answer 11

Hypofibrinogenemia

Question 12

When performing a factor VIII activity assay, a patient’s plasma is mixed with:

Answer 12

Factor VIII–deficient plasma

Question 13

The most suitable product for treatment of factor VIII deficiency is:

Answer 13

Factor VIII concentrate

Question 14

Which of the following is associated with an abnormal PLT aggregation test result?

A. Factor VIII deficiency
B. Factor VIII inhibitor
C. Lupus anticoagulant
D. Afibrinogenemia

Answer 14

Afibrinogenemia

Question 15

Refer to the following results:

PT = normal
APTT = prolonged
PLT count = normal
PLT aggregation to ristocetin = abnormal

Which of the following disorders may be indicated?

Answer 15

von Willebrand disease

Question 16

Which results are associated with hemophilia A?

Answer 16

Prolonged APTT, normal PT

Question 17

Fibrin monomers are increased in which of the following conditions?

Answer 17

DIC

Question 18

Which of the following is associated with multiple factor deficiencies?

Answer 18

Severe liver disease

Question 19

Normal PT and APTT results in a patient with poor wound healing may be associated with:

Answer 19

Factor XIII deficiency

Question 20

Fletcher factor (prekallikrein) deficiency may be associated with:

Answer 20

Thrombosis

Question 21

One of the complications associated with a severe hemophilia A is:

Answer 21

Hemarthrosis

(bleeding into the joints)

Question 22

The most common subtype of classic von Willebrand disease is:

Answer 22

Type 1

Question 23

Prolonged APTT and PT are corrected when mixed with normal plasma. Which factor is most likely deficient?

Answer 23

Factor V