Deck 14: Routine and Point-Of-Care Testing in Hematology: Manual and Semiautomated Methods

Question 1

For which patient is a hemoglobin of 10.5 g/dL normal?

A) A newborn
B) A 2-year-old child
C) A female adult
D) A male adult

Answer 1

A 2-year-old child

Question 2

Interpret the following results (all tests performed manually) on an adult female named Mary Jones.
RBC: 3.22*10¹²/L
Hemoglobin: 16.0 g/dL
Hematocrit: 30.0%

A) All are normal.
B) All are decreased.
C) Hemoglobin is elevated and other two are normal.
D) Values do not agree with the "rule of three."

Answer 2

Values do not agree with the "rule of three."

Question 3

In the center square on one side of a hemocytometer, 100 platelets were found; 200 were found in the center square on the other side. Select the best course of action.

A) Report the count as 150 *10⁹/L.
B) Verify the count by estimating the platelet number on the blood film.
C) Recount the hemocytometer on a phase microscope.
D) Repeat the procedure-the two counts are not close enough.

Answer 3

Repeat the procedure-the two counts are not close enough.

Question 4

Twenty cells are counted in one of the nine large squares of a hemocytometer. The sample is diluted 1:10. How many cells are present per $\mu$ L?

A) 200
B) 1000
C) 2000
D) 20,000

Question 5

Any of the following could be an explanation for the invalid hemoglobin for Mary Jones (Questions 13 through 16) except:

A) The blood sample is hemolyzed.
B) Lipemia is present in the plasma.
C) The patient has hemoglobin S (Hb S).
D) The patient's white count is 150.0 *10⁹/L.

Question 6

What is the total volume of one side of a hemocytometer if the ruled area is 3 * 3 mm and the depth is 0.1 mm?

A) 0.3 mm³
B) 0.9 mm³
C) 1.0 mm³
D) 9 mm³

Question 7

The platelet count from the automated cell counter is 80 * 10⁹/L. Platelet satellites around neutrophils are observed on the blood film estimate. A sodium citrate tube is drawn, and the count reads 300 *10⁹/L from the cell counter. What platelet count * 10⁹/L should be reported?

A) 80
B) 300
C) 330
D) The estimated count from the blood film

Question 8

The MCV on a patient is calculated to be 115 fL and the MCHC is 35 g/dL. What, in general terms, must be true of the MCH if it is consistent with the previous two indices?

A) It is impossible to know.
B) It should be in the reference range.
C) It should be below reference range.
D) It should be above reference range.

Question 9

What red cell morphology would support the red cell indices calculated for Mary Jones in Question 14?

A) Microcytic hyperchromic red cells
B) Normocytic hyperchromic red cells
C) Macrocytic hyperchromic red cells
D) No red cell morphology supports these indices.

Question 10

The calculated indices on Mary Jones from Question 13 are:

Question 11

A hemoglobin of 19 g/dL is normal for which of the following patients?

A) A newborn
B) A 2-year-old child
C) A female adult
D) A male adult

Question 12

What error was probably made if red cells are seen when attempting to manually count white blood cell (WBCs) on a hemocytometer?

A) The Unopette was not mixed before charging the hemocytometer.
B) Diluent was squeezed out and lost when filling the Unopette.
C) The wrong dilution was made.
D) The Unopette was not allowed to sit for 10 minutes for complete red blood cell (RBC) lysis.

Question 13

Which of the following could account for the red cell indices on Mary Jones reviewing Questions 13 through 15?

A) Determining a likely cause is not possible.
B) An error in the hemoglobin probably has been made.
C) An error in the red cell count probably has been made.
D) An error in the microhematocrit probably has been made.

Question 14

Why is it important to have a scrupulously clean hemocytometer when manually counting platelets?

A) So few platelets exist that they can be missed if dirt is present.
B) They are so refractile, they can be confused with dirt.
C) Their small size makes them easily confused with dirt.
D) They are easily confused with the red cells that are present.

Question 15

Ten nucleated red blood cells (NRBCs) are found in a blood film when differentiating 100 white cells. What is the corrected white blood count if the automated cell counter printed a count of 10.0* 10⁹/L?

A) 0.91* 10⁹/L
B) 9.1* 10⁹/L
C) 91 * 10⁹/L
D) Ten NRBCs not enough to require a correction

Question 16

Which of the following would cause a manual cell count to be falsely high?

A) Unopette not mixed before charging the hemocytometer
B) Not wiping excess blood from outside of pipette when filling
C) Using a smaller volume pipette than that specified by the Unopette system
D) Pulling blood out of the pipette when wiping away excess on the outside

Question 17

Manual cell counting methods in automated hematology laboratories are used for all of the following except:

A) Routine testing
B) Very low counts
C) Malfunctioning automated instruments
D) Counting spinal fluids

Question 18

Which of the following could cause the microhematocrit to be falsely decreased?

A) Specimen contaminated with intravenous fluid
B) Trapped plasma from abnormally shaped red cells
C) Dehydration
D) Insufficient centrifugation

Question 19

In the four large corner squares of a hemocytometer, 95, 102, 105, and 98 white cells were counted from a 1:20 dilution. Select the correct interpretation for the white blood count calculated from these values.

A) Normal for infant and elevated for an adult
B) Normal for any patient
C) Elevated for any patient
D) Normal for an infant and decreased for an adult

Question 20

On a standard reticulocyte preparation with new methylene blue, 100 cells are counted that contain blue-stained granulofilamentous material. The red blood count is 3.22 *10¹²/L, and the hematocrit is 30%. Calculate the reticulocyte count as a percentage.

A) 0.1%
B) 1.0%
C) 10.0%
D) 100.0%

Question 21

Diagnostic testing at or near the site of patient care is known as:

A) Preanalytic testing
B) Point-of-care testing (POCT)
C) Neutral-site testing
D) Clinical Laboratory Improvement Amendments (CLIA) testing

Question 22

A manual hemoglobin is determined on a patient, and the dilution still appears turbid after letting it sit for 15 minutes. The stained blood film is examined, and sickle cells are observed on the blood film. Equal volumes of the diluted hemoglobin sample and water are mixed together, and the absorbance of this read on a spectrophotometer. How should the hemoglobin result be determined from the standard calibrated graph?

A) Add the results from the turbid and second dilution together and divide by 2.
B) Multiply the result obtained from the graph on the diluted specimen by 2.
C) Divide the result obtained from the graph on the diluted specimen by 2.
D) There was no reason to perform this second dilution.

Question 23

Which of the following red cell indices support microcytic hypochromic red cell morphology?

Question 24

A 1:20 dilution of blood is made for a white count, and the following number of cells counted in the four large corner mm² of the hemocytometer: 12, 28, 18, and 15. What should be done next?

A) Report the white count as 3.7 *10⁹/L.
B) Clean the hemocytometer and recharge with a well-mixed dilution.
C) Increase the number of mm² counted.
D) Compare this cell count to the one on the other side.

Question 25

On a standard reticulocyte preparation with new methylene blue, 100 cells are counted containing blue-stained granulofilamentous material. The red blood count is 3.22 * 10^12/L, and the hematocrit is 30%. Calculate the reticulocyte production index (RPI).

A) 1.5
B) 2.7
C) 3.4
D) 13.4

Question 26

Which of the following red cell indices support macrocytic normochromic red cell morphology?

Question 27

A manual WBC count is performed using a system that makes a 1:20 dilution of blood. When the cells in the four large corner mm² of the hemocytometer are counted, the following numbers of cells are obtained: 8, 12, 9, and 11. What would be the next step?

A) Count the cells in all 9 mm² of the hemocytometer.
B) Redo the dilution of blood using a new 1:20 dilution.
C) Redo the dilution of blood using a 1:100 dilution.
D) Calculate the count using the values from the 4 mm² and report the result.

Question 28

Which of the following is a good use of the erythrocyte sedimentation rate (ESR)?

A) Monitor patients with rheumatoid arthritis.
B) Diagnose acute appendicitis.
C) Diagnose multiple myeloma.
D) Monitor patients with osteoarthritis.

Question 29

Which of the following red cell indices support normocytic normochromic red cell morphology?

Question 30

On a standard reticulocyte preparation with new methylene blue, 100 cells are counted containing blue-stained granulofilamentous material. The red blood count is 3.22 *10^12/L, and the hematocrit is 30%. Calculate the corrected reticulocyte count.

A) 1.5%
B) 3.0%
C) 6.7%
D) 15.0%

Question 31

On a standard reticulocyte preparation with new methylene blue, 100 cells are counted containing blue-stained granulofilamentous material. The red blood count is 3.22 * 10^12/L, and the hematocrit is 30%. Calculate the absolute reticulocyte count.

A) 0.32* 10¹²/L
B) 3.2 *10¹²/L
C) 32.2*10¹²/L
D) 0.99 * 10¹²/L

Question 32

On a standard reticulocyte preparation with new methylene blue, 100 cells are counted containing blue-stained granulofilamentous material. The red blood count is 3.22 * 10^12/L, and the hematocrit is 30%. Using information determined from Questions 23 through 27, what is the correct interpretation for this patient's condition?

A) Microcytic anemia with inadequate bone marrow response
B) Macrocytic anemia with adequate bone marrow response
C) Normocytic anemia with inadequate bone marrow response
D) Normocytic anemia with adequate bone marrow response

Question 33

What make RBCs settle faster through the plasma when inflammation or infection exist?

A) Bacteria cause red cells to agglutinate and fall faster.
B) Increased number of neutrophils cause red cells to form rouleaux.
C) Inflammation makes the plasma less viscous.
D) Acute phase reactant proteins disrupt the electrical charge that normally separates cells.

Question 34

Which of the following can cause a falsely increased ESR?

A) Concentration of anticoagulant increased
B) Tube not totally vertical
C) Tuberculosis
D) Increased plasma viscosity

Question 35

On a standard reticulocyte preparation with new methylene blue, 100 cells are counted containing blue-stained granulofilamentous material. The red blood count is 3.22 * 10^12/L, and the hematocrit is 30%. Calculate the MCV.

A) 80 fL
B) 93 fL
C) 98 fL
D) 108 fL

Question 36

The following RBC indices are obtained on a patient when calculated using results from manual methods:
MCV: 73 fL
MCH: 24 pg
MCHC: 33.4 g/dL
When the stained blood film is evaluated, the RBCs are normocytic normochromic. What conclusion can be made from this information?

A) The hematocrit is too low.
B) The hemoglobin is too low.
C) The red count is too high.
D) It is impossible to come to any conclusion.

Question 37

How do sickle cells or spherocytes interfere with the ESR?

A) Prevent rouleaux formation, so falsely decrease
B) Encourage rouleaux formation, so falsely increase
C) Agglutinate and increase red cell mass, so falsely increase
D) Decrease plasma viscosity, so falsely decrease