Deck 37: Hematology Procedures

Question 1

How does the anticoagulant EDTA prevent coagulation from occurring?

A) Binds calcium in a soluble complex
B) Enhances antithrombin activity
C) Chelates calcium ions
D) Inhibits factor XII activity

Answer 1

Chelates calcium ions

Question 2

What is the anticoagulant in the most commonly utilized tube in hematology, and how does it prevent coagulation from taking place?

A) Sodium citrate; chelates calcium
B) EDTA; chelates calcium
C) Heparin; neutralizes thrombin
D) Sodium citrate; decreases thrombin activity

Answer 2

EDTA; chelates calcium

Question 3

The ESR determination on the MINI-VES instrument is based on:

A) Decrease in height of the erythrocyte column at a given time
B) Decrease in absorbance as erythrocytes aggregate in column at a given time
C) Distance that the erythrocytes settle within a column in 1 hour
D) Deflection of light by the erythrocyte aggregates in the column at 1

Answer 3

Decrease in height of the erythrocyte column at a given time

Question 4

Which of the following is the most appropriate test to differentiate hemoglobin S trait from hemoglobin S disease?

A) Quantitation of hemoglobin A₂
B) Hemoglobin electrophoresis
C) Acid elution for hemoglobin F
D) Solubility for hemoglobin S

Question 5

A sickle solubility test is requested STAT on a 45-year-old patient who is to have surgery very soon. The technologist receives the sample and immediately takes the reagent out from the refrigerator and performs the test. It comes back positive. The surgery is postponed until hemoglobin electrophoresis is performed, and it shows a normal distribution of adult hemoglobins. What is the most likely reason for the discrepant result?

A) There was a false positive on the sickle solubility test because of the cold reagent.
B) The hemoglobin electrophoresis findings need to be confirmed on acid gel.
C) There was a false negative on the sickle solubility test because of inadequate mixing.
D) The wrong patient was drawn.

Question 6

The function of a microscope's condenser is to:

A) Adjust the magnification of the slide against the viewer's eye
B) Direct light onto the slide
C) Hold the slide
D) Regulate the amount of light projected onto the slide

Question 7

Which of the following is not mandated by OSHA?

A) The use of two patient identifiers when collecting blood samples
B) The use of plastic tubes when performing venipuncture
C) Education regarding regulation of the transmission of blood-borne pathogens
D) Education regarding regulation of needle sticks

Question 8

Given an RBC count of 3.25 × 10¹²/L, a hemoglobin of 9.0 g/dL, and a hematocrit of 25%, how will the red cells appear under PB smear examination?

A) Normocytic
B) Macrocytic
C) Microcytic
D) Hyperchromic

Question 9

The 18-gauge needles used to collect donor blood for transfusion have a larger bore than do standard blood collection needles. What is the advantage of this needle?

A) The needle minimizes discomfort to the donor.
B) The needle allows for tube holder and vacutainer use.
C) The phlebotomist has better technique with a larger needle.
D) The collection process is faster, and less hemolysis occurs.

Question 10

A CBC is performed on a polycythemic patient. What must the laboratician do to ensure that this specimen has an optimal blood smear?

A) Increase the angle of the spreader slide
B) Decrease the angle of the spreader slide
C) Not change the angle of the spreader slide
D) Stain with albumin

Question 11

The following erythrocyte indices were determined as part of a CBC: MCV 84 fL, MCH 24 pg, and MCHC 30 g/dL. What would you expect to observe on the Wright-stained peripheral blood smear?

A) Normochromic, normocytic erythrocytes
B) Hypochromic, microcytic erythrocytes
C) Hypochromic, normocytic erythrocytes
D) Normochromic, macrocytic erythrocytes

Question 12

Which of the following receptacles is most appropriate when disposing of used needles?

A) A regular garbage can
B) A biohazard bag
C) A biohazard sharps container
D) A regular garbage bag

Question 13

The microscopic examination of a Wright-stained blood smear revealed bright red erythrocytes and pale leukocyte nuclei. What is the best explanation for this appearance?

A) The buffer is too acidic.
B) The staining process was prolonged.
C) The blood smear was too thick.
D) The Wright stain was too alkaline.

Question 14

A laboratory professional is reviewing differentials and notices that the last few smears appear blue. What can be done to correct this?

A) Lengthen the staining time
B) Change the buffer solution, which might be too alkaline
C) Change the buffer solution, which might be too acidic
D) Decrease the staining time

Question 15

All of the following are needed on a phlebotomist's supply tray to perform a venipuncture except:

A) Needles
B) Tourniquets
C) Gauze
D) Lancets

Question 16

The reference interval for hemoglobin varies with age. Which of the following age groups is associated with the highest hemoglobin level?

A) Adults over 75 years old
B) Adults between 25-35 years old
C) Children 2-8 years old
D) Newborns

Question 17

Proper technique for the capillary puncture includes:

A) Wiping the first drop of blood away from the puncture
B) Squeezing the puncture site prior to use of the lancet
C) Placing an ice pack on the puncture site prior to collection
D) Performing the puncture immediately following alcohol cleansing

Question 18

An instrument printout reports a WBC count of 18 × 10⁹/L. The technologist notes 44 nucleated red blood cells. What is the corrected WBC count?

A) 18.4 × 10⁹/L
B) 15.8 × 10⁹/L
C) 8.3 × 10⁹L
D) 12.5 × 10⁹/L

Question 19

The following erythrocyte data were obtained from an EDTA-anticoagulated sample: erythrocyte count = 3.92 × 10¹²/L, hemoglobin = 11.4 g/dL, and hematocrit = 34% (.34 L/L). Calculate the MCHC.

A) 29.1 g/dL
B) 33.5 g/dL
C) 67.2 g/dL
D) 86.7 g/dL

Question 20

The resolution of a microscope is a function of:

A) Numerical aperture
B) Wavelength of reflected light
C) Refractive index
D) Presence of chromatic aberrations

Question 21

In phase contrast microscopy, the function of the phase ring is to:

A) Direct light through its open circular area
B) Retard the wavelength of deflected light
C) Project the beam of light onto the sample
D) Diffract the light from the condenser

Question 22

Which laboratory test is useful in the differential diagnosis of polycythemia?

A) EPO
B) sTfR
C) Hct
D) MCV

Question 23

A patient is about to begin a regimen of chemotherapy, and his attending physician has ordered a battery of lab tests including comprehensive chemistry metabolic panel, complete blood count, coagulation studies, amylase and lipase, hemoglobin A1C, lipid panel, thyroid panel, PSA, rubella IgG, HIV, and syphilis. Five tiger-top tubes, 2 light blue-top tubes, and 2 lavender-top tubes are needed. Correlate each test to the appropriate tube and indicate the correct order of draw for the tubes.

Question 24

A technologist is performing differentials and notices that all the slides he has reviewed appear pink. What is the best way to correct this problem?

A) Change the buffer so that it is more acidic
B) Change the buffer so that it is more alkaline
C) Clean the slides and make a new smear
D) Filter the stain used

Question 25

A patient has difficult veins, and a winged infusion set is used to collect the blood from a small vein in the patient's hand. After successfully filling all the SST tubes, the phlebotomist proceeds to fill the light blue-top tube but is unsuccessful. She changes tubes, thinking that it might be a tube with a lost vacuum, but there is still no blood flow. She inspects the entry site and notices some bruising around it that was not present before. Discuss possibilities of the unsuccessful draw, and explain how to correct them.

Question 26

A patient's osmotic fragility test results show beginning hemolysis at 0.40% NaCl and complete hemolysis at 0.20% NaCl. Increased numbers of which erythrocyte morphology are associated with these findings?

A) Schistocytes
B) Tear drop cells
C) Spherocytes
D) Target cells

Question 27

Which cytochemical stain is useful in differentiating CML from a leukemoid reaction?

A) PAS
B) LAP
C) MPO
D) TRAP

Question 28

An instrument printout reports a platelet count of 85 10⁹/L. The technologist reviewing the peripheral blood smears notices aggregates of platelets around many of the neutrophils. What is the best way to correct this problem?

A) Warm the specimen for 10 minutes at 45°C and rerun the sample
B) Centrifuge and rerun the sample
C) Remake the smear and use alkaline buffer to stain the slide
D) Redraw the sample in sodium citrate and repeat the platelet count

Question 29

A panel of cytochemical stains is performed to determine a patient's subtype of AML. Myeloperoxidase and Sudan Black B are positive. Specific esterase is positive and nonspecific esterase o is negative. Based on this information, what lineage is implicated as the chosen subtype of AML?

A) Lymphoid
B) Myeloid
C) Monocytic
D) Erythroid

Question 30

A patient had the following results: RBC 2.45 × 10¹²/L MCV 90 fL
Hb 7.5 g/dL MCH 31 pg
Hct 22.0% MCHC 34 g/dL
DAT negative
Haptoglobin 10 mg/dL
(Reference range: 35-164 for males and 40-175 for females)
Which is the most appropriate reflex test?

A) Reticulocyte count
B) Hemoglobin electrophoresis
C) Osmotic fragility test
D) Erythropoietin assay

Question 31

Increased levels of Heinz bodies are seen in which of the following?

A) Thalassemia
B) G6PD deficiency
C) AML
D) Sickle cell anemia

Question 32

The acid elution test for hemoglobin F was performed on a patient sample, and examination of the slide revealed an uneven distribution of hemoglobin F within the erythrocytes. Control slides were acceptable. Which of the following is associated with this observation?

A) Iron deficiency anemia
B) Sickle cell anemia
C) Pernicious anemia
D) Hereditary persistence of fetal hemoglobin

Question 33

Which substance when added to the acid phosphatase stain is useful in the identification of hairy cells?

A) Sodium fluoride
B) Sodium tartrate
C) Potassium chloride
D) Disodium phosphate

Question 34

Which cytochemical stain is useful in differentiating myeloblasts and lymphoblasts?

A) PAS
B) LAP
C) MPO
D) TRAP

Question 35

Brilliant green is used as the stain of choice for Heinz body preparation because of:

A) Its sensitivity for detecting small amounts of Heinz bodies present
B) Its specificity for differentiating Heinz bodies from other inclusions
C) Its ease of use and minimal teratogenic effects on the personnel utilizing it
D) The fact that it keeps the cells alive to accurately visualize it

Question 36

Two incubation sessions are needed in the Donath-Landsteiner test to detect:

A) The biphasic thermal reactivity of the offensive antibody
B) Complement binding in vivo
C) The antibody's specificity to the P antigen in vitro
D) The antibody's specificity to group O cells

Question 37

Acid is used in the quantification of hemoglobin F laboratory test because:

A) Fetal cells are resistant to acid, which facilitates quantification of hemoglobin F
B) Adult cells are resistant to acid, which facilitates quantification of hemoglobin F
C) Acid inhibits other interfering hemoglobins
D) Acid lyses RBCs to release hemoglobin F

Question 38

In the chloroacetate esterase procedure, which reagent component undergoes color change because of the enzyme's activity?

A) Hematoxylin
B) Diazonium salt
C) 3,3 diaminobenzidine
D) Naphthol AS-D chloroacetate

Question 39

A clinical laboratory professional observes numerous smudge cells on a Wright-stained blood smear and experiences difficulty performing the 100-cell differential. What should be done to obtain an accurate differential?

A) Recollect the sample using sodium citrate and prepare a blood smear
B) Warm the blood to 37°C for 15 minutes and prepare a blood smear
C) Add one drop of isotonic saline to five drops of blood, mix, and prepare blood smear
D) Add one drop of 22% bovine albumin to five drops of blood, mix, and prepare a blood smear

Question 40

An instrument printout reports a WBC count of 12 10⁹/L. The technologist reviews the peripheral blood smear and counts 45 nucleated RBCs. What is the best course of action regarding these findings?

A) Repeat the instrument count after making a 1:10 dilution
B) Make a new smear with albumin
C) Adjust the WBC count for the presence of nRBCs
D) Warm the specimen

Question 41

The following are preliminary screening test results. Name the suspected disorder associated with each finding, and explain how you would confirm each.
a. Positive hemolysis after both incubation periods
b. Normal sTFR levels
c. Many spherocytes noted on PB smear
d. Blasts noted on PB smear

Question 42

Name the cytochemical stains that are typically used in the workup of the following and how they are used to differentiate these conditions:
a. AML-myelomonocytic
b. APL
c. ALL
d. AML-Monoblastic
e. AML-Erythroid

Question 43

List corrective measurements for each of the following:
a. A good monolayer on a blood smear in a patient with a low hematocrit
b. A good monolayer on a blood smear in a patient with a high hematocrit
c. Platelet satellitism
d. Many smudge cells on PB smear

Question 44

Describe necessary steps for preventative maintenance of your microscope.