Thrombosis
pregnancy and birth control pills cause increase/ decrease risk of thrombosis
increased
_________________________is a
quantitative platelet disorder associated with
increased intravascular platelet activation and
aggregation resulting in thrombocytopenia. The
PT and APTT results
Thrombotic thrombocytopenic purpura (TTP)
Which factors are involved in the intrinsic pathway ?
XII, XI, IX, VIII
A patient has an increased PT and a normal APTT . What factor is most likely deficient?
VII
Disseminated intravascular coagulation (DIC) is
most often associated with which of the following
types of acute leukemia?
Acute promyelocytic leukemia
Factor V Leiden promotes thrombosis by
being resistant to protein C
!rombotic thrombocytopenic purpura (TTP) is
characterized by:
A. Prolonged PT
B. Increased platelet aggregation
C.!rombocytosis
D. Prolonged APTT
B Thrombotic thrombocytopenic purpura (TTP) is a
quantitative platelet disorder associated with
increased intravascular platelet activation and
aggregation resulting in thrombocytopenia. The
PT and APTT results are normal in TTP
Which of the following is a characteristic of classic
hemophilia A?
A. Prolonged bleeding time
B. Autosomal recessive inheritance
C. Mild to severe bleeding episodes
D. Prolonged PT
C.
Hemophilia A is a factor VIII deficiency
Bleeding time and PT normal
It is also a X chromosome linked gene so not autosomal
A prolonged APTT is corrected with factor
VIII– deficient plasma but not with factor
IX–deficient plasma. Which factor is deficient?
A. V
B. VIII
C. IX
D. X
Factor IX
!e most suitable product for treatment of factor
VIII deficiency is:
Factor VIII concentrate
________ is heparin cofactor and it is the most
important naturally occurring physiological inhibitor
of blood coagulation.
Antithrombin aka antithrombin III
_______is a platelet receptor for VWF.
_________ and VWF are both necessary for a
normal platelet ______.
glycoprotein 1b
adhesion
Normal PT and APTT results in a patient with a
poor wound healing may be associated with what factor deficiency
Factor XIII
A prolonged APTT and PT are corrected when
mixed with normal plasma. Which factor is most
likely deficient?
A. VIII
B. V
C. XI
D. IX
V
A fresh blood sample was sent to the laboratory at
8:00 a.m. for a PT test. At 4:00 p.m., the doctor
requested an APTT test to be done on the same
sample. What should the technologist do?
request a new sample : APPT only good for 4 hours
________ functions as a cofactor of protein C and
as such enhances its activity. Activated protein C
inactivates factors Va and VIIIa.
Protein S
____________ is associated with
thrombocytopenia and giant platelets. It is a
qualitative platelet disorder caused by the
deficiency of glycoprotein Ib.
Bernard - Soulier syndrome
the activity of lupus anticoagulant appears to be directed against?
phospholipids
prolonged APPT and thrombosis seen with no correction with mixing studies
Mrs. Smith has the following laboratory results,
and no bleeding history:
APTT: prolonged
APTT results on a 1:1 mixture of the patient’s plasma
with normal plasma:
Preincubation: prolonged APTT
2-hour incubation: prolonged APTT
These results are consistent with:
lupus anticoagulant
Which factors would be affected by Vitamin K deficiency and what would happen to the PT and APTT results of these patients
II, VII, IX, X
both would be increased
Which of the following alleles has the highest
frequency in the general population?
A. #F508 (cystic fibrosis)
B. Factor V-Leiden (hereditary thrombophilia)
C. Prothrombin G20210A (hereditary
thrombophilia)
D. Methylene tetrahydrofolate reductase mutation
C677T homocysteinemia
D MTHFR- found in about 30% population - increased risk of thrombosis
Aspirin prevents platelet aggregation by inhibiting
the action of which enzyme?
Cyclo-oxygenase
This
inhibition prevents the formation of thromboxane A2
(TXA2), which serves as a potent platelet aggregator.
a phleb collects blood for an aPTT on patient at 10am . The blood was collected in a sodium citrate tube . At 4:30 pm the phleb finds the tube on her tray and realizes she forgot to send to the lab. She immediately sends it to the lab. describe the most likely effect to the results.
Why ?
Falsely elevated aPTT ..
why ?
test is only good for 4 hours mainly because factors V and VIII are labile and deteriorate fast at room Temp
Which test may be used to monitor LMWH ( low molecular weight heparin)
therapy?
anti- factor Xa
Which of the following does not contribute to the activation of the fibrinolytic system?
a. XIIa
b. XIa
c. Kallikrein
d. Tissue plasminogen activator
B ..
remember all others loop back to feed into fibrinolysis.. this is why deficiency of factor XII actually leads to thrombosis not bleeding