CHAPTER 37 Flashcards
- The clinical presentation of platelet-related bleeding may include all of the following except:
a. Bruising
b. Nosebleeds
c. Gastrointestinal bleeding
d. Bleeding into the joints
(hemarthroses)
d. Bleeding into the joints
(hemarthroses)
- A defect in GP IIb/IIIa causes:
a. Glanzmann thrombasthenia
b. Bernard-Soulier syndrome
c. Gray platelet syndrome
d. Storage pool disease
a. Glanzmann thrombasthenia
- Patients with Bernard-Soulier syndrome have which of the following laboratory test findings?
a. Abnormal platelet response to
arachidonic acid
b. Abnormal platelet response to
ristocetin
c. Abnormal platelet response to
collagen
d. Thrombocytosis
b. Abnormal platelet response to
ristocetin
- Which of the following is the most common of the hereditary platelet function defects?
a. Glanzmann thrombasthenia
b. Bernard-Soulier syndrome
c. Storage pool defects
d. Multiple myeloma
c. Storage pool defects
- A reduction in thrombin generation in patients with Scott syndrome results from:
a. Defective granule secretion
b. Altered platelet aggregation
c. Altered expression of
phospholipids on the platelet
membrane
d. Deficiency of vitamin K-dependent
clotting factors
c. Altered expression of
phospholipids on the platelet
membrane
- The impaired platelet function in
myeloproliferative neoplasms results from:
a. Abnormally shaped platelets
b. Extended platelet life span
c. Increased procoagulant activity
d. Decreased numbers of a granules
and dense granules
d. Decreased numbers of a granules
and dense granules
- The platelet defect associated with increased paraproteins is:
a. Impaired membrane activation,
owing to protein coating
b. Hypercoagulability, owing to antibody
binding and membrane activation
c. Impaired aggregation, because the
hyperviscous plasma prevents
platelet-endothelium interaction
d. Hypercoagulability, because the
increased proteins bring platelets closer
together, which leads to inappropriate
aggregation
a. Impaired membrane activation,
owing to protein coating
- In uremia, platelet function is impaired by higher than normal levels of:
a. Urea
b. Uric acid
c. Creatinine
d. NO
d. NO
- Thrombocytopenia associated with the use of cardiopulmonary bypass is not caused by:
a. Anti-GP IIb/IIIa antibodies
b. Hemodilution
c. Platelet binding to bypass circuitry
d. Platelet consumption associated with
normal postsurgical hemostatic activity
a. Anti-GP IIb/IIIa antibodies
- A mechanism of antiplatelet drugs targeting GP IIb/IIIa function is:
a. Interference with platelet adhesion to
the subendothelium by blocking of the
collagen binding site
b. Inhibition of transcription of the GP
IIb/IIIa gene
c. Direct binding to GP IIb/IIIa
d. Interference with platelet secretion
c. Direct binding to GP IIb/IIIa
- Aspirin ingestion blocks the synthesis of:
a. Thromboxane A2
b. Ionized calcium
c. Collagen d. ADP
a. Thromboxane A2
- Which is a congenital qualitative platelet
disorder?
a. Senile purpura
b. Ehlers-Danlos syndrome
c. Henoch-Schönlein purpura
d. Waldenström macroglobulinemia
b. Ehlers-Danlos syndrome
- A defect in primary hemostasis (platelet
response to an injury) often results in:
a. Musculoskeletal bleeding
b. Mucosal bleeding
c. Hemarthroses
d. None of the above
b. Mucosal bleeding
- The autosomal dominant disorder associated with decreased platelet production is:
a. Fanconi anemia
b. TAR syndrome
c. May-Hegglin anomaly
d. Wiskott-Aldrich anomaly
c. May-Hegglin anomaly
- Which of the following is not a hallmark of ITP?
a. Petechiae
b. Thrombocytopenia
c. Large overactive platelets
d. Megakaryocyte hypoplasia
c. Large overactive platelets
- The specific antigen most commonly
responsible for the development of NAIT is:
a. Bak
b. HPA-1a
c. GPIb
d. Lewis antigen a
b. HPA-1a
- A 2-year-old child with an unexpected platelet count of 15,000/mL and a recent history of a viral infection most likely has:
a. HIT
b. NAIT
c. Acute ITP
d. Chronic ITP
c. Acute ITP
- Which drug causes a reduction in platelet
count by inhibiting megakaryocyte
maturation?
a. Gold salts
b. Abciximab
c. Anagrelide
d. Quinidine
c. Anagrelide
- When a drug acts as a hapten to induce
thrombocytopenia, an antibody forms against which of the following?
a. Typically unexposed, new platelet
antigens
b. The combination of the drug and
the platelet membrane protein to
which it is bound
c. The drug alone in the plasma, but the
immune complex then binds to the
platelet membrane
d. The drug alone, but only when it is
bound to the platelet membrane
b. The combination of the drug and
the platelet membrane protein to
which it is bound
- TAR refers to:
a. Abnormal platelet morphology in
which the radial striations of the
platelets are missing
b. Abnormal appearance of the iris of
the eye in which radial striations are
absent
c. Abnormal bone formation,
including hypoplasia of the forearms
d. Neurologic defects affecting the root
(radix) of the spinal nerves
c. Abnormal bone formation,
including hypoplasia of the forearms
- Neonatal autoimmune thrombocytopenia occurs when:
a. The mother lacks a platelet antigen
that the infant possesses, and she
builds antibodies to that antigen, which
cross the placenta
b. The infant develops an autoimmune
process such as ITP secondary to in
utero infection
c. The infant develops an autoimmune
disease such as lupus erythematosus
before birth
d. The mother has an autoimmune
antibody to her own platelets, which
crosses the placenta and reacts with
the infant’s platelets
d. The mother has an autoimmune
antibody to her own platelets, which
crosses the placenta and reacts with
the infant’s platelets
- HUS in children is associated with:
a. Diarrhea caused by Shigella
species
b. Meningitis caused by Haemophilus
species
c. Pneumonia caused by Mycoplasma
species d. Pneumonia caused by
respiratory viruses
a. Diarrhea caused by Shigella
species
- Treatment with an anticomplement agent such as eculizumab is first-line therapy for:
a. Hereditary TTP
b. Hemolytic uremic syndrome (HUS)
c. ITP
d. Atypical HUS
d. Atypical HUS
- Which of the following statements regarding thrombocytosis is not true?
a. Thrombocytosis can be associated
with hemorrhage and thrombosis
b. Affected patients have platelet counts
in excess of 450,000/mL
c. Thrombocytosis is self-correcting
d. Thrombocytosis can be congenital or
acquired
c. Thrombocytosis is self-correcting
- What is the prevalence of venous thrombosis in the United States?
a. 0.01
b. 1 in 1000
c. 10% to 15%
d. 500,000 cases per year
b. 1 in 1000
- What is thrombophilia?
a. Predisposition to thrombosis
secondary to a congenital or
acquired disorder
b. Inappropriate triggering of the plasma
coagulation system
c. A condition in which clots form
uncontrollably
d. Inadequate fibrinolysis
a. Predisposition to thrombosis
secondary to a congenital or
acquired disorder
- What acquired thrombosis risk factor is
assessed in the hemostasis laboratory?
a. Smoking
b. Immobilization
c. Obesity
d. Lupus anticoagulant
d. Lupus anticoagulant
- Trousseau syndrome, a low-grade chronic DIC, is often associated with what type of disorder?
a. Renal disease
b. Hepatic disease
c. Adenocarcinoma
d. Chronic inflammation
c. Adenocarcinoma
- What is the most common heritable
thrombosis risk factor in Caucasians?
a. APC resistance (factor V Leiden
mutation)
b. Prothrombin G20210A mutation
c. Antithrombin deficiency
d. Protein S deficiency
a. APC resistance (factor V Leiden
mutation)
- In most LAC profiles, what test is primary
(performed first) because it detects LAC with the least interference?
a. Low-phospholipid PTT
b. DRVVT
c. KCT
d. PT
b. DRVVT
- A patient with venous thrombosis is tested for protein S deficiency. The protein S activity, antigen, and free antigen are all less than 65%, and the C4bBP level is normal. What type of deficiency is likely?
a. Type I
b. Type II
c. Type III
d. No deficiency is indicated, because the
reference range
includes 65%
a. Type I
- An elevated level of what fibrinolytic system assay is associ- ated with arterial thrombotic risk?
a. PAI-1
b. TPA
c. FactorVIIa
d. Factor XII
a. PAI-1
- How does lipoprotein (a) cause thrombosis?
a. It causes elevated factor VIII levels
b. It coats the endothelial lining of
arteries
c. It substitutes for plasminogen or
TPA in the forming clot
d. It contributes additional phospholipid
in vivo for formation of the tenase
complex
c. It substitutes for plasminogen or
TPA in the forming clot
- What test may be used to confirm the
presence of LAC?
a. PT
b. Bethesda titer
c. Antinuclear antibody
d. DRVVT using high-phospholipid
reagent
d. DRVVT using high-phospholipid
reagent
- What molecular test may be used to confirm APC resis- tance?
a. Prothrombin G20210A
b. MTHFR 1298
c. MTHFR 677
d. Factor V Leiden
d. Factor V Leiden
- What therapeutic agent may occasionally cause DIC?
a. FactorVIII
b. Factor VIIa
c. Antithrombin concentrate
d. Activated prothrombin complex
concentrate
d. Activated prothrombin complex
concentrate
- Which is not a fibrinolysis control protein?
a. Thrombin-activatable fibrinolysis
inhibitor
b. Plasminogen activator inhibitor-1
c. a2-Antiplasmin
d. D-dimer
d. D-dimer
- What is the most important application of the quantitative D-dimer test?
a. Diagnose primary fibrinolysis
b. Diagnose liver and renal disease
c. Rule out deep venous thrombosis
d. Diagnose acute myocardial infarction
c. Rule out deep venous thrombosis
- What is the first laboratory assay necessary to detect heparin- induced thrombocytopenia?
a. Platelet count
b. H:PF4 immunoassay
c. Quick turnaround test
d. Serotonin release assay
a. Platelet count
- What is the PT/INR therapeutic range for
Coumadin therapy when a patient has a
mechanical heart valve?
a. 1 to 2
b. 2 to 3
c. 2.5 to 3.5
d. Coumadin is not indicated for patients
with mechanicalheart valves
c. 2.5 to 3.5