This document provides instructions for examining a peripheral blood film under a microscope at different magnifications. It describes examining the smear macroscopically and then microscopically at 10x, 40x, and 100x objectives. Key steps include estimating white blood cell counts, performing differential counts to classify white blood cells, estimating platelet counts, and examining red blood cell morphology. Abnormal findings for red blood cells, white blood cells, and platelets are defined.

1. Prepared by
HadeelAl Sadoun
Examine peripheral blood film

2. How you examine Blood film
 Macroscopic Examination
 10x objective Examination
 40x objective Examination
 100x objective – oil Immersion Examination

3. Macroscopic Examination
 Examine the smear before placing on the microscope.
(Why?)
 To indicate abnormalities:
 Example: (over all blurred smear  increased blood proteins
:multiple Myeloma)

4. Microscopic Examination
 Microscope should be properly adjusted on the area of blood
smear will be examined.
 The light from the illuminator should be properly centered.
 Condenser should be placed all the way up.
 Iris diaphragm must be opened

5. 10x objective Examination
 This magnification power must not be skipped for the following
reasons:
 Quick scanning of over all smear quality
 Assess the distribution of the RBCs.
 AssessWBC distribution
 Large abnormal cells can be seen example:
 Blast
 Reactive lymphocytes
 Unexpected parasites

6. 40x objective examination
 Easy to select the examination area as well as 10x objective
examination.
 WBC estimation
 The examiner should select an area where two or more RBC
overlapped and all other are evenly separated
 Count theWBC number regardless of there type in 10 fields
 Use this equation:
 Average no. ofWBC/ field x 2000= cells/ µL
 NormalWBC estimate ranges from : 5,000 – 10,000 cell/µL

7. 100 objective- oil immersion
Examination
 Used forWBC differential count
 Classify 100WBC into (PMN, Lymphocytes, Monocytes, eosinophiles and
basophiles)
 For Platelets estimate and morphology
 Count platelet in 10 fields under 100x.
 Use the following equation:
 Average no. of Platelets/ field x 20,000 = cell/ µL
 Normal range of platelets = 150,000 – 350, 000 cell/ µL
 RBC morphology and nucleated RBC examination and count

8. Basophiles
Esionphils
Monocytes
Lymphocytes
PMN
10-14µm
12-17µm
12-18µm
varies
12-14µm
Bilobed with large
dark blue granules
may obscure the
nucleus
Bilobed with large
red-orange
granules.
Nucleus folded, or
kidney shaped,
chromatin is less
dens than
lymphocytes.Very
fine azurophilic
granules.
Large:12-16µm,
nucleus is round ,
coarse chromatin
Small: 9-12µm,
nucleus is round ,
coarse
chromatin, High
N:C ratio.
Multilobed (2-4)
nucleus connected
by thin strands
(0-2%)
(1-4%)
(1-10%)
(18-42%)
(48-70%)

9. Platelet morphology
 Normal platelets:
 Size: 1-3 µm
 Only seen under 100x objective magnification.
 Irregular outlines
 fine- violet granulation (scattered or centralized)
 Giant platelets:
 Size: 4-5 µm
 Same features of morphology

10. RBC Morphology
 Normal RBC:
 Size: 6.8- 7.2 µm
 central pallor, not vaculated or graulated.
 Abnormalities in size:
 Microcytic RBC: size less than 6µm
 Macrocytic RBC: size more than 8 µm
 Variation in RBC sizes called anisocytosis

11.  Abnormalities in hemoglobin concentration:
 Hypochromic: pale RBC less hemoglobin available than normal
 Hyperchromic: dark red RBC , concentrated Hemoglobin

12. RBC morphology
 Abnormal shapes of RBC:
 Stomatocyte
 Target cell
 Eleptocyte
 Variation of the cell shape in field called poikilocytosis

13. How to evaluate RBC, WBC and platelet
morphology
 If abnormal cell present:
 Examine 10 fields:
 If 0-2 cell seen in 10 field : +
 If 2-4 cells seen in 10 field: ++
 If 5-7 cells seen in 10 field : +++