lab test for primary hemostasis

Question 1

which of the following does not belong to thrombocytosis

a. PV
b. idiopathic thrombocythemia
c. thrombocytopenia purpura
d. CML

Answer 1

PLATELET COUNT

> Reference value= 150-400 x10 9 /L, 150 to 450 x10 9 (Rodak’s)

❖ Thrombocytosis:   (PICS)
        PV, 
        idiopathic thrombocythemia, 
        CML,
        splenectomy 

❖ Thrombocytopenia: thrombocytopenia purpura, aplastic anemia, acute leukemia, pernicious anemia, Gaucher’s disease (PATAG)

Question 2

which of the following does not belong to thrombocytopenia

a. CML
b. pernicious anemia
c. thrombocytepenia purpura
d. gaucher’s disease

Answer 2

answer :  CML
Thrombocytopenia:  (PATAG)
       Pernicious anemia
       aplastic anemia
       thrombocytopenia purpura
       acute leukemia
       Gaucher's disease

Thrombocytosis:   (PICS)
        PV, 
        idiopathic thrombocythemia, 
        CML,
        splenectomy

Question 3

ideal microscope for platelet count

a. bright field
b. fluorescent
c. dark field
d. phase contrast

Answer 3

Dilution factor : 1:100

Squares counted : Count 25/25 squares or 10 tertiary squares of the center square

Ideal microscope : Phase contrast microscope

Question 4

If fewer than 50 platelets counted on each side = repeat procedure and dilute blood to _____

a. 1:100
b. 1:200
c. 1:20
d. 1:1

Answer 4

A. If fewer than 50 platelets counted on each side = repeat procedure and dilute blood to 1:20

B. If more than 500platelets counted on each side = repeat procedure and dilute blood to 1:200

Question 5

which of the following methods of platelet count belong to direct

a. dameshek
b. tonkantin method
c. olek
d. guy and leake

Answer 5

direct
  1. Reese Ecker  / Tonkantin method
  2, Guy and Leake
  3.  Brecker
  4. unopette

indirect (DOF)

1. Dameshek
2. olek’s
3. Fonio

Question 6

normal platelet count + prolonged BT

a. qualitative platelet abnormlaity
b. autoimmune thrombocytopenia
c. Simultaneous quantitative and qualitative platelet deficiency
d. Von Willebrand’s syndome

Answer 6

Normal Platelet count + prolonged BT
✓ Qualitative platelet abnormality
✓ Primary vascular abnormality
✓ Von Willebrand’s syndrome

Question 7

low platelet count + normal BT

a. qualitative platelet abnormlaity
b. autoimmune thrombocytopenia
c. Simultaneous quantitative and qualitative platelet deficiency
d. Von Willebrand’s syndome

Answer 7

Normal Platelet count + prolonged BT
✓ Qualitative platelet abnormality
✓ Primary vascular abnormality
✓ Von Willebrand’s syndrome

Lowplatelet count + Normal BT
✓ Autoimmune thrombocytopenia

Low Platelet count + very prolonged BT
✓ Simultaneous quantitative and qualitative platelet deficiency

Question 8

gold standard test to determine platelet function

a. platelet count
b. platelet aggregation
c. platelet adhesiveness
d. clot retraction time

Answer 8

PLATELET AGGREGATION TEST

❖ In vitro test to determine the ability of platelet to aggregate with certain agonist

❖ Platelet aggregation is the gold standard test to determine platelet function

❖ The principle of the test is that platelet-rich plasma is TREATED WITH KNOWN AGGREGATING AGENT. If aggregated, cloudiness or turbidity can be measured using a spectrophotometer.

Question 9

An instrument designed to measure platelet aggregation in a suspension of citrated whole blood or PRP (Platelet Rich Plasma)

A. aggregometer

b. epinephrine
c. Collagen
d. Arachidonic acid

Answer 9

Aggregometer

   An instrument designed to measure platelet aggregation in a suspension of citrated whole blood or PRP (Platelet Rich Plasma)

Question 10

Agonist that is stored at 1° C to 6° C and reconstituted with distilled water immediately before it is used

A. aggregometer

b. epinephrine
c. Collagen
d. Arachidonic acid

Answer 10

ADP and thrombin
Agonists that are stored at –20° C, reconstituted with PHYSIOLOGIC SALINE, and used immediately after reconstitution

Epinephrine
Agonist that is stored at 1° C to 6° C and reconstituted with DISTILLED WATER immediately before it is used

Question 11

Agonist that is stored at 1° C to 6° C and used without further dilution. It cannot be frozen

A. aggregometer

b. epinephrine
c. Collagen
d. Arachidonic acid

Answer 11

Collagen

• Agonist that is stored at 1° C to 6° C and used without further dilution.
• It cannot be frozen

Arachidonic acid

• Agonist that is READILY OXIDIZED and must be stored at –20° C in the DARK OR DARK BOTTLE.
• It must be DILUTED WITH BOVINE SOLUTION for immediate use.

Question 12

which of the following is most common agonist

a. ADP
b. Collagen
c. Epinephrine
d. Thrombin

Answer 12

Agonists (ACE TAR)

ADP - most common agonists
COLLAGEN
EPINEPHRINE

THROMBIN
ARACHIDONIC ACID
RISTOCETIN