Leukocyte Differential Count

Question 1

Blood collection & Smear steps

Answer 1

1) Patient wash hands (warm water)
2) Disinfect with alcohol on cotton swab
3) Open needle (twist & pull)
4) Discard in yellow bin
5) After prick, wipe off first drop (due to interstitial fluid & debris)
6) Pick up drop with edge of a microscopic slide & smear (3 specimens)
7) Let dry until matte before staining

Question 2

Blood smear staining Steps

Answer 2

1) Undiluted May-Grünwald solution for 3 minutes
2) Diluted May-Grünwald for 1 minute
3) Diluted Giemsa solution for 15-20 minutes
4) Wash with distilled water and let dry

Question 3

Undiluted May-Grünwald Solution

Answer 3

• Methanol containing methylene-blue & eosin
• Basophilic Staining
• Ensures Fixation

Question 4

Diluted May-Grünwald Solution

Answer 4

May-Grünwald solution that has been diluted twofold with distilled water (1:2 ratio)

Question 5

Diluted Giemsa Solution

Answer 5

• Glycerol solution containing azur-eosin
• Diluted 15x with 6mM phosphate buffer (pH 6.8)
• Eosinophilic staining

Question 6

How to view Stained slide on Microscope?

Answer 6

1) Apply a drop of Immersion oil to avoid high refraction
2) View at 100x magnification
3) Count cells in a meandering pattern (like snake) & identify
4) Count 100, and make percentages of how many of each type there were

Question 7

Neutrophil normal %

Answer 7

60 - 70%

Question 8

Lymphocytes normal %

Answer 8

25 - 30%

Question 9

Monocytes normal %

Answer 9

4 - 8%

Question 10

Eosinophil normal %

Answer 10

2 - 4%

Question 11

Basophil normal %

Answer 11

0 - 1%

Question 12

Neutrophil size

Answer 12

10 - 14μm

Question 13

Lymphocyte size

Answer 13

6 - 8μm

Question 14

Monocyte size

Answer 14

18 - 21μm

Question 15

Eosinophil size

Answer 15

10 - 14μm

Question 16

Basophil size

Answer 16

8 - 12μm