CHAPTER 14: MANUAL, SEMIAUTOMATED, AND POINT-OF-CARE TESTING IN HEMATOLOGY

Question 1

(1) A 1:20 dilution of blood is made with 3% glacial acetic acid as the diluent. The four large corner squares on both sides of the hemacytometer are counted, for a total of 100 cells. What is the total WBC count (x 10^9/L)?

a. 0.25
b. 2.5
c. 5
d. 10

Answer 1

b. 2.5

Question 2

(2) The total WBC count is 20 x 10^9/L. Twenty-five nRBCs per 100 WBCs are observed on the peripheral blood film. What is the corrected WBC count (x10^9/L)?

a. 0.8
b. 8
c. 16
d. 19

Answer 2

c. 16

Question 3

(3) If potassium cyanide and potassium ferricyanide are used in the manual method for hemoglobin determination, the final product is:

a. Methemoglobin
b. Azide methemoglobin
c. Cyanmethemoglobin
d. Myoglobin

Answer 3

c. Cyanmethemoglobin

Question 4

(4) Which of the following would not interfere with the result when hemoglobin determination is performed by the cyanmethemoglobin method?

a. Increased lipids
b. Elevated WBC count
c. Lyse-resistant RBCs
d. Fetal hemoglobin

Answer 4

d. Fetal hemoglobin

Question 5

(5) A patient has a hemoglobin level of 8.0 g/dL. According to the rule of three, what is the expected range for the hematocrit?

a. 21% to 24%
b. 23.7% to 24.3%
c. 24% to 27%
d. 21% to 27%

Answer 5

d. 21% to 27%

Question 6

(6) Calculate the MCV and MCHC for the following values:
RBCs = 5.00 3 1012/L
HGB = 9 g/dL
HCT = 30%

a. MCV (fL) = 30; MCHC (g/dL) = 18
b. MCV (fL) = 60; MCHC (g/dL) = 30
c. MCV (fL) = 65; MCHC (g/dL) = 33
d. MCV (fL) = 85; MCHC (g/dL) = 35

Answer 6

b. MCV (fL) = 60; MCHC (g/dL) = 30

Question 7

(7) What does the reticulocyte count assess?

a. Inflammation
b. Response to infection
c. Erythropoietic activity of the bone marrow
d. Ability of red blood cells to form rouleaux

Answer 7

c. Erythropoietic activity of the bone marrow

Question 8

(8) For a patient with the following test results, which measure of bone marrow red blood cell production provides the most accurate information?

Observed reticulocyte count = 5.3%
HCT 5=35%
Morphology—moderate polychromasia

a. Observed reticulocyte count
b. Corrected reticulocyte count
c. RPI
d. ARC

Answer 8

b. Corrected reticulocyte count

Question 9

(9) Given the following values, calculate the RPI:

Observed reticulocyte count = 6%
HCT = 30%

a. 2
b. 3
c. 4
d. 5

Answer 9

a. 2

Question 10

(10) Which of the following would be associated with an elevated ESR value?

a. Microcytosis
b. Polycythemia
c. Decreased globulins
d. Inflammation

Answer 10

d. Inflammation