Platelet Function Testing

Question 1

Designed to detect qualitative (function) platelet
abnormalities in patients with symptoms of mucocutaneous bleeding.

Answer 1

Platelet Function Testing

Question 2

REMINDER‼️‼️‼️‼️

Platelet count and blood film is reviewed before the test.

Question 3

Original platelet function test, now obsolete.

Answer 3

Bleeding Time Test

Question 4

Bleeding time testing

First described by __________ and. _______________

Answer 4

Duke (1912) and modified by Ivy (1941)

Question 5

Platelet adhesion, aggregation and secretion are assessed using ___________________

Answer 5

in-vitro platelet aggregometry

Question 6

an instrument designed to measure platelet
function in a suspension of Citrated WB or PRP.

Answer 6

Aggregometer

Question 7

Samples use in aggregometer

Answer 7

Citrated WB - 3.2% sodium citrate ( 18-24°C)
Platelet Rich Plasma- Platelet count must be (200-300 x 10^9/ L)

Question 8

Types of Platelet Aggregometry Studies

Answer 8

1. Optical platelet aggregometry
2. Whole blood platelet aggregometry
3. Platelet Lumiaggregometry

Question 9

Optical platelet aggregometry sample used

Answer 9

PRP

Question 10

Optical platelet aggregometry testing principle

Answer 10

Light transmittance aggregometry

Question 11

Baseline 0% Transmission scales down to 100% transmittance.

Answer 11

Optical platelet aggregometry

Question 12

Optical platelet aggregometry
5 Phases

Answer 12

1. Baseline
2. Shape Change
3. Primary-wave aggregation
4. ADP/ATP release
5. Second-wave aggregation

Question 13

Whole blood platelet aggregometry
- Sample used

Answer 13

Whole blood (WB)

Question 14

Whole blood platelet aggregometry
Testing principle

Answer 14

Electrical impedance

Question 15

Whole blood platelet aggregometry
Working temp:

Answer 15

37 c

Question 16

As platelet aggregate, platelets collects on the electrodes impeding the current. The change is amplified and recorded.

Answer 16

Whole blood platelet aggregometry

Question 17

Platelet Lumiaggregometry
- Sample used:

Answer 17

Whole blood (WB) or PRP

Question 18

Platelet Lumiaggregometry
Testing principle

Answer 18

Chemiluminescence

Question 19

Platelet Lumiaggregometry
Working temp

Answer 19

37 C

Question 20

What reagent is added in platelet lumiaggregometry

Answer 20

Luciferin-luciferase enzyme (Reagent)

Question 21

Luciferin-luciferase enzyme (Reagent) work

Answer 21

oxidized by ATP which generates proportional chemiluminescence.

Question 22

Agonist Used In Aggregometry

Answer 22

1. Thrombin
2. ADP
3. Epinephrine
4. Collagen
5. Arachidonic acid
6. Ristocetin

Question 23

biphasic curves

Answer 23

1. Thrombin
2. ADP
3. Epinephrine

Question 24

monophasic curves

Answer 24

4. Collagen
5. Arachidonic acid
6. Ristocetin

Question 25

Thrombin receptor

Answer 25

PAR-1,PAR-4;
GPIba & GPVI

Question 26

ADP receptor

Answer 26

P2Y1 & P2Y12

Question 27

Epinephrine receptor

Answer 27

A2-Adrenergic receptor

Question 28

Relatively unaffected by membrane disorders or
enzyme deficiencies.

Answer 28

Thrombin

Question 29

Most commonly used agonist.

Answer 29

ADP

Question 30

Cannot induce aggregation in storage pool disorders

Answer 30

Epinephrine

Question 31

Collagen receptor

Answer 31

GPIa/IIa & GPVI

Question 32

Arachidonic acid receptor

Answer 32

TPa and TPb

Question 33

Ristocetin receptor

Answer 33

GPIb/IX/V with vWF