Examination of Peripheral Blood Film and Correlation with the Complete Blood Count

Question 1

A peripheral blood film provides valuable information regarding a patient’s health; hence, it should be:

Answer 1

1. well-made;
2. well-stained; and
3. carefully examined.

Question 2

the “capstone” of the Complete
Blood Count (CBC)

Answer 2

PBF

Question 3

PBF specimen

Answer 3

FRESH WHOLE BLOOD samples collected in EDTA

Question 4

liquid form in glass tubes; mixes readily with blood

Answer 4

Tripotassium EDTA (K3EDTA)

Question 5

powdered or spray-dried form in plastic tubes

Answer 5

Dipotassium EDTA (K2EDTA)

Question 6

Blood should be processed within

Answer 6

4 hours

Question 7

what happens when Plasma hypertonicity occur?

Answer 7

RBCs will shrink

Question 8

• Platelets surround or adhere to neutrophils
• This in-vitro phenomenon results in falsely
  decreased platelet count (pseudothrombocytopenia)

Answer 8

Platelet satellitosis

Question 9

• Platelets aggregate to form masses of similar
  size to WBCs
• This in-vitro phenomenon results in falsely
  elevated WBC count (pseudoleukocytosis)

Answer 9

Platelet agglutination

Question 10

are samples collected without anticoagulant

Answer 10

• FRESH CAPILLARY (capillary or skin puncture)
• VENOUS BLOOD (venipuncture syringe method)

Question 11

The easiest to master, the most convenient, and the most commonly used technique for making peripheral blood film

Answer 11

MANUAL WEDGE TECHNIQUE

Question 12

Manual wedge technique glass slides measurement

Answer 12

3-inch x 1-inch (75mm x 25mm)

Question 13

Blood drop size

Answer 13

2 to 3mm

Question 14

angle of spreader slide

Answer 14

30 to 45 degrees

Question 15

Other factor to consider the angle of spreader slide

• Extremely low hct:
• higher hct:

Answer 15

• Extremely low hct: angle needs to be RAISED
• higher hct: angle should be LOWERED

Question 16

Acidic (or anionic) dye:
Basic (or cationic) dye:

Answer 16

• Eosin
• Methylene blue

Question 17

The force of attraction or repulsion between unlike and like charges, respectively.

Answer 17

Coulombic attraction

Question 18

fixes the cells to the slide:

Answer 18

Methanol

Question 19

stains basic components,
e.g., hemoglobin and eosinophil granules →
“eosinophilic” or “acidophilic”

Answer 19

Acidic (anionic) dye: Eosin

Question 20

stains acidic components, e.g., nucleic acids (DNA and RNA) and basophil granules → “basophilic”

Answer 20

Basic (cationic) dye: Methylene blue

Question 21

buffer solution

Answer 21

Phosphate buffer (0.05M sodium phosphate, pH 6.4)

Question 22

MACROSCOPIC EXAMINATION

PBF has holes all over the film:

Answer 22

increased blood lipid levels (lipemia)

Question 23

MACROSCOPIC EXAMINATION

PBF has a grainy appearance:

Answer 23

RBC agglutination (cold agglutinin disease)

Question 24

MACROSCOPIC EXAMINATION

PBF has blue specks at the feathery edge:

Answer 24

markedly increased WBC and platelet counts

Question 24

MACROSCOPIC EXAMINATION

PBF appears too blue:

Answer 24

increased blood protein levels (multiple myeloma, gammopathy)

Question 25

is the best possible area of the peripheral blood film where morphology assessments are
performed

Answer 25

Zone of Morphology

Question 26

is a “panel” essentially divided into RBC, WBC, and Platelet parameters, which are interpreted together to provide the best information.

Answer 26

CBC

Question 27

OPTIMAL ASSESSMENT AREA

RBCs are uniformly and singly distributed,
with few touching or overlapping, and have their normal biconcave appearance (central pallor)

Answer 27

Optimal area

Question 28

OPTIMAL ASSESSMENT AREA

This distorts RBCs and WBCs by piling them on top of one another, making morphologic
evaluation difficult and potentially incorrect classification.

Answer 28

Too-thick area

Question 29

OPTIMAL ASSESSMENT AREA

The film has holes, and the RBCs look
flat, large, and distorted.

Answer 29

Too-thin area