Sysmex/CBC Review

Question 1

The electronic impedance cell counter depends on:

Answer 1

The cell being less conductive than the isotonic diluent

Question 2

What best describes the cell counting principle of Sysmex automated blood analyzers?

Answer 2

Direct current and hydrodynamic focused flow impedance

Question 3

What is the type of measurement utilized by the Sysmex system for Hemoglobin?

Answer 3

measured photometrically & directly

Question 4

What information does forward scatter provide about a cell?

Answer 4

Measures cell size

Question 5

How is the MCH calculated?

Answer 5

HGB/RBC

Question 6

How is the MCV calculated?

Answer 6

HCT X 1000/RBC

Question 7

How is the MCHC calculated?

Answer 7

HGB/HCT

Question 8

How is the HCT calculated?

Answer 8

MCV X RBC COUNT/1000

Question 9

RULE OF 3, HCT FORMULA

Answer 9

HGB X 3/1000 = HCT +/- 0.03 L/L

Question 10

RULE OF 3, HGB FORMULA

Answer 10

RBC X 30 = HGB +/- 15G/L

Question 11

Why do laboratories subscribe to External Proficiency Testing?

Answer 11

It is further check of result accuracy

Question 12

What best describes the method used to determine the total WBC counts on the Sysmex analyzers?

Answer 12

Fluorescence flow cytometry

Question 13

What method is used to measure Hemoglobin on an automated cell analyzer?

Answer 13

Photometric method

Question 14

What is the type of measurement utilized by the Sysmex system for WBC?

Answer 14

Measured directly using impedance technology

Question 15

Drabkin’s reagent for the measurement of hemoglobin by the cyanmethemoglobin uses the following reagents.

Answer 15

Potassium ferricyanide and potassium cyanide

Question 16

What best explains/demonstrates a QC “shift”?

Answer 16

A sudden change in QC values that are consecutive either above or below the mean

Question 17

What information does Side scatter provide about a cell?

Answer 17

Cytoplasmic granularity and nuclear configuration

Question 18

What is Low Voltage DC used to measure?

Answer 18

Total cell volume

Question 19

What is the type of measurement utilized by the Sysmex system for Hematocrit?

Answer 19

Measured directly by rbc cumulative pulse height detection

Question 20

What is the type of measurement utilized by the Sysmex system for RBC?

Answer 20

measured directly using impedance – DC detection

Question 21

Automated differential analysis can be based on?

Answer 21

Granularity of WBC cytoplasm, conductivity, light scattering

Question 22

What is the type of measurement utilized by the Sysmex system for MCH?

Answer 22

Calculated using directly measured or derived parameters

Question 23

What method is used to measure RBC/ size and number on the Sysmex Cell analyzer?

Answer 23

Direct Current/ Hydrodynamic focusing

Question 24

What best describes the method used to detect the presence of immature myeloid cells on the Sysmex cell analyzer?

Answer 24

Radio frequency / Direct current

Question 25

Floating discriminators and/or thresholds (electronically set size limits) are used to

Answer 25

distinguish between RBC's and platelets

Question 26

The cyanmethemoglobin method of hemoglobin determination measures all forms of hemoglobin EXCEPT:

Answer 26

Sulfhemoglobin

Question 27

What is laminar flow?

Answer 27

movement of two liquids past one another without mixing

Question 28

What is the basis for the impedance principle of cell counting and sizing?

Answer 28

Cells create a resistance, when passed through an electrical current that is directly proportional to the volume or size of that cell

Question 29

What action needs to be taken with a critical hemoglobin value?

Answer 29

Check for a clot and repeat the test

Question 30

What action is recommended when platelet aggregates or platelet satellitosis are found on the peripheral blood smear?

Answer 30

Recollect specimen 4.5 ml whole blood in a 3.2% Sodium Citrate and multiple platelet results by 1.1

Question 31

Which CBC parameters best indicate a possible iron deficiency?

Answer 31

↓HGB & ↓MCV & ↑RDW

Question 32

How are CBC results affected by cold agglutinins?

Answer 32

Falsely decreasing the HCT

Question 33

Under what conditions would an RBC histogram from an automated cell analyzer shift to the right?

Answer 33

Megaloblastic anemia

Question 34

Which RBC parameters indicate normochromic RBCs?

Answer 34

MCHC, MCH

Question 35

What parameter best indicates the presence of red cell agglutination?

Answer 35

MCHC

Question 36

Which of the following would result in falsely high hemoglobin?

Answer 36

A greatly elevated WBC count

Question 37

When examining the peripheral blood smear and Complete Blood count, which parameter should be examined after the hemoglobin and Hematocrit?

Answer 37

MCV

Question 38

Under what conditions would an RBC histogram from an automated cell analyzer shift to the left?

Answer 38

Chronic blood loss

Question 39

Which CBC parameters best indicate a possible thalassemia?

Answer 39

↑RBC,↓MCV, & HGB = N

Question 40

When reviewing a CBC result with a normal MCV, which CBC parameter best alerts the operator that the results may not be accurate?

Answer 40

MCHC