How to Examine a Blood Film
Reem Alsolami Compound Microscope Parts
How to examine Blood film
Macroscopic Examination e.g. Over all blurred smear is caused by increased blood proteins in Multiple Myeloma 10x objective Examination
40x objective Examination
100x objective –oil Immersion Examination
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
See the explaining video
10x objective Examination
Quick scanning of over all smear quality Assess the distribution of the RBCs. Assess WBC distribution Most importantly to define the EXAMINATION AREA Large abnormal cells can be seen example: Blast Reactive lymphocytes Unexpected parasites
Examination Area 40x objective (For WBC estimation)
40x objective examination
WBC Estimation Count the WBC number regardless of there type in 10 fields Use this equation: Total number of counted WBC/ number of fields x 2000= WBC cells/ μL 3 9 • Remember μL-> x10 ; L-> x 10 /L • e.g. 5000 WBC cells / µL-> 5 x103/µL 5 x 109 /L Normal WBC Reference range : 5 x 103 - 10 x 103 / µL
100x objective-oil immersion Examination
• For Platelets estimation
• For RBC morphology evaluation
• For WBC differentiation Platelets estimation • Normal Size: 1-3 μm
• Irregular outlines • Fine-violet granulation (scattered or centralized) • Giant platelets: • Size: 4-5 μm • Same features of morphology
Platelets estimation
Count platelet in 10 fields under 100x.
Use the following equation:
Total 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
RBC morphology A. Evaluate RBC morphology based on their size(cytic), and colour (chromic). Normocytic Normochromic ( normal peripheral blood and some type of leukaemia like the one associated with leukaemia. -Size of normal RBC: 6.8-7.2 μm -Central pallor, not vacuolated or granulated Microcytic hypochromic (IDA, thalassemia) Macrocytic normochromic ( Megaloblastic anaemia, and folic acid deficiency).
1 2 3 RBC morphology B. Report any abnormal RBC shapes
WBC Differential
PMN Typical small monocyte Basophil Eosinophil Lymphocyte 12-14μm 9-12 µm 12-18μm 12-17μm 10-14μm
Multilobed(2-4) .High N:C Nucleus Bilobed with Bilobed with nucleus ratio. folded, or large red- large dark blue connected by .Round kidney orange granules may thin strands nucleus shaped, granules. obscure the .Round cell chromatin is nucleus .Chromatin less dens than condensed lymphocytes. Very fine azurophilic granules (48-70%) (18-42%) (1-10%) (1-4%) (0-2%) Absolute WBC cell type Count
• Total count of leukocytes x one type of WBC = Absolut count of this cell type 100
• The unit is dependent on the total leukocyte, for example if the total WBC count is /L the result will be in /L , and if it is /µL , the result of the Absolute will be /µL .
• Example What is the absolute count of neutrophil? How to write your report
• See the word document • See future hematology teaching video