1.1 basic hematology concepts and lab procedures

Insufficient centrifugation will result in:

A. A false increase in hematocrit (Hct) value
B. A false decrease in Hct value
C. No effect of Hct value
D. All of these options, depending on the patient

A. a false increase in hematocrit (Hct) value

Which of the following is the preferred site for bone marrow aspiration and biopsy in adult?

A. Iliac crest
B. Sternum
C. Tibia
D. Spinous process of a vertebra

A. lliac crest

Mean cell volume (MCV) is calculated by using the following formula:

A. (Hgb / RBC) x 10, where Hgb is hemoglobin in g/dL
B. (Hct / RBC) x 10
C. (Hct / Hgb) x 100
D. (Hgb / RBC) x 100

B. (Hct / RBC) x 10

Variation in red blood cell (RBC) size observed on the peripheral blood smear is described as:

A. Anisocytosis
B. Hypochromia
C. Poikilocytosis
D. Pleocytosis

A. Anisocytosis

What term describes the change in shape of erythrocytes seen on a Wright-stained peripheral blood smear?

A. Poikilocytosis
B. Anisocytosis
C. Hypochromia
D. Polychromasia

A. Poikilocytosis

Calculate the mean cell hemoglobin concentration (MCHC) by using the following values:
Hgb: 15 g/dL (150 g/dL)
Hct: 47 mL/dL (0.47)
RBC: 4.50 x 10^6/uL (4.50 x 10^12/L)

A. 9.5% (0.095)
B. 10.4% (0.104)
C. 31.9% (0.319)
D. 33.3% (0.333)

C. 31.9% (0.319)

(Hgb / Hct) x 100

A manual white blood cell (WBC) count was performed. In total, 36 cells were counted in all 9-mm2 squares of a Neubauer-ruled hemacytometer. A 1:10 dilution was used. What is the WBC count?

A. 0.4 x 10^9/L
B. 2.5 x 10^9/L
C. 4.0 x 10^9/L
D. 8.0 x 10^9/L

A. 0.4 x 10^9/L

When an erythrocyte containing iron granules is stained with Prussian blue, the cell is called a:

A. Spherocyte
B. Leptocyte
C. Schistocyte
D. Siderocyte

D. Siderocyte

A 7.0-mL ethylenediaminetetraacetic acid (EDTA) tube is received in the laboratory containing only 2.0 mL of blood. If the laboratory is using manual techniques, which of the following tests will most likely be erroneous?

A. RBC count
B. Hgb
C. Hct
D. WBC count

C. Hct

A 1:200 dilution of a patient's sample was made and 336 RBCs were counted in an area of 0.2 mm2. What is the RBC count?

A. 1.68 x 10^12/L
B. 3.36 x 10^12/L
C. 4.47 x 10^12/L
D. 6.66 x 10^12/L

B. 3.36 x 10^12/L

What phagocytic cells produce lysozymes that are bacteriocidal?

A. Eosinophils
B. Lymphocytes
C. Platelets (PLTs)
D. Neutrophils

D. Neutrophils

If a patient has a reticulocyte count of 7% and Hct of 20%, what is the corrected reticulocyte count?

A. 1.4%
B. 3.1%
C. 3.5%
D. 14%

B. 3.1%

Corrected retic count = retic % x (Hct / 45)

A decreased osmotic fragility test would be associated with which of the following conditions?

A. Sickle cell anemia
B. Hereditary spherocytosis
C. Hemolytic disease of the fetus and newborn
D. Acquired hemolytic anemia

A. Sickle cell anemia

What effect would using a buffer at pH 6.0 have on a Wright-stained smear?

A. RBCs would be stained too pink
B. WBC cytoplasm would be stained too blue
C. RBCs would be stained too blue
D. RBCs would lyse on the slide

A. RBCs would be stained too pink

Which of the following erythrocyte inclusions can be visualized with supravital stain but cannot be detected on a Wright-stained blood smear?

A. Basophilic stippling
B. Heinz bodies
C. Howell-Jolly bodies
D. Siderotic granules

B. Heinz bodies

A falsely elevated Hct is obtained. Which of the following calculated values will NOT be affected?

A. MCV
B. MCH
C. MCHC
D. Red blood cell distribution width (RDW)

B. MCH

A Miller disk is an ocular device used to facilitate counting of:

A. PLT
B. Reticulocytes
C. Sickle cells
D. Uncleared red blood cells (NRBCs)

B. Reticulocytes

RBC indices obtained on an anemic patient are as follows:
MCV = 88 um3 (fL)
MCH = 30 pg
MCHC = 34% (0.340).

The RBCs on the peripheral blood smear would appear:

A. Microcytic, hypochromic
B. Microcytic, normochromic
C. Normocytic, normochromic
D. Normocytic, hypochromic

C. Normocytic, normochromic

All of the following factors may influence the erythrocyte sedimentation rate (ESR) except:

A. Blood drawn into a sodium citrate tube
B. Anisocytosis, Poikilocytosis
C. Plasma proteins
D. Caliber of the tube

A. Blood drawn into a sodium citrate tube

What staining method is used most frequently to stain and manually count Reticulocytes?

A. Immunofluorescence
B. Supravital staining
C. Romanowsky staining
D. Cytochemical staining

B. Supravital staining

The Coulter principle for counting of cells is based on the fact that:

A. Isotonic solutions conduct electricity better than cells do
B. Conductivity varies proportionally to the number of cells
C. Cells conduct electricity better than saline does
D. Isotonic solutions cannot conduct electricity

A. Isotonic solutions conduct electricity better than cells do

A correction is necessary for WBC counts when NRBCs are seen on the peripheral blood smear because:

A. The WBC count would be falsely lower
B. The RBC count is too low
C. NRBCs are counted as leukocytes
D. NRBCs are confused with giant PLTs

C. NRBCs are counted as leukocytes

Given the following values, which set of RBC indices suggest spherocytosis?

A. MCV: 76 fL, MCH: 19.9 pg, MCHC: 28.5%
B. MCV: 90 fL, MCH: 30.5 pg, MCHC: 32.5%
C. MCV: 80 fL, MCH: 36.5 pg, MCHC: 39.0%
D. MCV: 81 fL, MCH: 29.0 pg, MCHC: 34.8%

C. MCV: 80 fL, MCH: 36.5 pg, MCHC: 39.0%

Which of the following statistical terms reflects the best index of precision when comparing two complete blood count (CBC) parameters?

A. Mean
B. Median
C. Coefficient of variation
D. Standard deviation

C. Coefficient of variation

Which of the following is considered a normal Hgb?

A. Carboxyhemoglobin
B. Methemoglobin
C. Sulfhemoglobin
D. Deoxyhemoglobin

D. Deoxyhemoglobin

Which condition will shift the oxyhemoglobin dissociation curve to the right?

A. Acidosis
B. Alkalosis
C. Multiple blood transfusions
D. Increased quantities of Hgb S or C

A. Acidosis

What is the major type of leukocyte seen in the peripheral blood smear from a patient with aplastic anemia?

A. Segmented neutrophil
B. Lymphocyte
C. Monocyte
D. Eosinophil

B. Lymphocyte

What is the normal WBC differential lymphocyte percentage (range) in the adult population?

A. 5 - 10%
B. 10 - 20%
C. 20 - 44%
D. 50 - 70%

C. 20 - 44%

In which age group would 60% lymphocytes be a normal finding?

A. 6 months - 2 years
B. 4 - 6 years
C. 11 - 15 years
D. 40 - 60 years

A. 6 months - 2 years

Which of the following results on an automated differential suggests that a peripheral blood smear should be reviewed manually?

A. Segs = 70%
B. Bands = 6%
C. Mono = 15%
D. Eos = 2%

C. Mono = 15%

Which is the first stage of erythrocytic maturation in which the cytoplasm is pink because of the formation of Hgb?

A. Reticulocyte
B. Pronormoblast
C. Basophilic normoblast
D. Polychromatic normoblast

D. Polychromatic normoblast

Which of the following can shift the Hgb oxygen (O2) dissociation curve to the right?

A. Increases in 2,3 DPG
B. Acidosis
C. Hypoxia
D. All of these options

D. All of these options

Which of the following Hgb configurations is characteristic of Hgb H?

A. Gamma 4
B. Alpha 2-gamma 2
C. Beta 4
D. Alpha 2-beta 2

C. Beta 4

Autoagglutination of RBCs at room temperature can cause which of the following abnormal test results?

A. Low RBC count
B. High MCV
C. Low Hct
D. All of these options

D. All of these options