Deck 15: Examination of the Peripheral Blood Film and Correlation With the Complete Blood Count

Question 1

Macroscopic holes in a blood film most likely mean the patient has:

A) Increased blood proteins
B) Red cell agglutination
C) Increased lipids
D) Increased white blood count

Answer 1

Increased lipids

Question 2

Coverslip smears are used primarily for:

A) High white blood counts
B) Bone marrow aspirates
C) Finger and heel punctures
D) Polycythemia patients with high red counts

Answer 2

Bone marrow aspirates

Question 3

Select the correct interpretation for the number of eosinophils (EOs) if the white count is 10.0 *10⁹/L and 20% EOs are noted on the manual differential?

A) Relative and absolute eosinophilia
B) Relative and absolute eosinopenia
C) Indirect counts not valid; repeat with EO Unopette and phloxine stain
D) Normal

Answer 3

Relative and absolute eosinophilia

Question 4

Methods, such as using a fan to dry blood films faster, are especially important when:

A) The patient is very anemic or high humidity exists.
B) The patient has polycythemia or high humidity exists.
C) The sample is over 6 hours old.
D) No one is available to blow on the blood film.

Question 5

How can the correct platelet count on a patient be determined when his or her platelets repeatedly clump in an EDTA specimen?

A) Re-collect in sodium citrate tube (blue top) and multiply by 0.5.
B) Re-collect in sodium citrate tube (blue top) and multiply count by 1.1.
C) Report the estimated number from the blood film.
D) Re-collect in an EDTA tube.

Question 6

The methanol in Wright stain:

A) Establishes the alkaline pH need for staining
B) Fixes the cells
C) Establishes the acid pH needed for staining
D) Serves no function except as a solvent for the dyes

Question 7

A blood specimen could not be focused on oil immersion although it could be focused on both *10 and *40. What is the most likely cause?

A) The pH of the stain is too acidic.
B) The specimen is too thick.
C) Something is wrong with the oil lens.
D) The specimen is probably upside down.

Question 8

When examining a blood specimen on oil immersion, the red cells appear flat, large, and distorted. An average of 100 red cells is noted per oil field. Select the best course of action.

A) Go to a thicker area of the specimen.
B) Go to a thinner area of the specimen.
C) Make a new specimen.
D) Collect a new sample.

Question 9

A patient's blood film had marked echinocytes and many broken and vacuolated neutrophils. The same patient's blood film the day before did not show these features. Select the best course of action.

A) Report the results.
B) Make a new film.
C) Disregard these findings as artifact.
D) Collect a new sample and make the film within 5 hours.

Question 10

Why is the complete blood count (CBC) the most frequently ordered clinical laboratory test?

A) Easy to perform
B) Inexpensive
C) Provides valuable information about the patient's overall health status
D) Anticoagulated blood easy to obtain

Question 11

Clumped platelets will cause which of the following spurious results when cell counts are performed on an automated hematology analyzer?

A) Platelets low and white count high
B) Platelets high and white count low
C) Platelets low and white count unaffected
D) Platelets low and hemoglobin high

Question 12

What is the most common reason for blood films having red cells that are gray and white cells that are too dark?

A) Overrinsing
B) Buffering for too short a time
C) Stain or buffer is too acidic
D) Stain or buffer is too alkaline

Question 13

In the appropriate area of a well-made blood film, two to three white cells are seen per high dry field. The automated cell counter white count on the same patient is 20.6 *10⁹/L. Select the correct interpretation.

A) The estimate matches the count; report the results.
B) The estimate does not match the count; investigate labeling error.
C) Repeat the estimate on oil immersion.
D) Rerun the sample through the cell counter.

Question 14

All of the following can be determined from a blood film except:

A) Red cell morphology
B) White cell estimate
C) Red cell estimate
D) Platelet estimate

Question 15

While examining a stained blood film under *10, a significantly disproportionate number of monocytes are seen at the sides and in the featheredge of the blood film. What should be done?

A) Exclude these cells from the *100 differential evaluation.
B) Nothing; this finding is not significant.
C) Make and stain a new slide.
D) Add 2% more to the number of monocytes counted in the white cell differential.

Question 16

Select the best course of action to remedy blood films that typically are too thick from newborns.

A) Increase the spreader slide angle.
B) Use a larger drop.
C) Dilute the blood with saline.
D) Decrease the spreader slide angle.

Question 17

A decreased white count is called:

A) Leukocytosis
B) Leucopenia
C) Thrombocytosis
D) Thrombocytopenia

Question 18

What term is used to describe a variation in the size of RBCs?

A) Anisocytosis
B) Microcytosis
C) Spherocytosis
D) Poikilocytosis

Question 19

When is it advisable to count 200 instead of 100 white cells for a differential?

A) The technologist is inexperienced.
B) The physician requests it.
C) The white blood count is elevated.
D) The white blood count is decreased.

Question 20

Select the normal approximate percentage of the various WBCs in an adult. Neut Band EO Baso Lymph Mono

A) 63 2 4 1 25 5
B) 29 11 9 11 10 30
C) 60 2 4 11 4 19
D) 59 26 1 1 11 2

Question 21

The presence of spherocytes in blood can:

A) Elevate the mean cell volume (MCV)
B) Elevate the erythrocyte sedimentation rate (ESR)
C) Elevate the mean cell hemoglobin concentration (MCHC)
D) Elevate the WBC count.

Question 22

The term used to describe a decrease in all blood cell numbers in the peripheral blood is:

A) Leukopenia
B) Lymphopenia
C) Neutropenia
D) Pancytopenia

Question 23

The presence of polychromatophilic RBCs on a blood film suggest that there will be:

A) An increase in the reticulocyte count
B) Decreased production of RBCs in the bone marrow
C) Neutrophilia
D) Lymphopenia

Question 24

The white count on an adult patient is 2.2 *10⁹/L. When the blood film is examined, the following results are obtained: 15% neutrophils and 75% lymphocytes. Reference ranges for these cells types, both relative and absolute, are as follows:

What conclusion can be made about the number of lymphocytes for this patient?

A) They are relatively increased but normal in absolute numbers.
B) They are both relatively and absolutely increased.
C) They are relatively decreased but absolutely increased.
D) They are both relatively and absolutely decreased.

Question 25

When anisocytosis is present, all the following are true except:

A) Variation in size of red cells should be observed on the blood film.
B) The RDW should be increased.
C) Variation in shape of red cells should be observed on the blood film.
D) Anemia is likely present.