Transcript DIFFERENTIAL LEUCOCYTE COUNT (DLC)

DIFFERENTIAL LEUCOCYTE COUNT
(DLC)
HMIM BLOCK 224
Dr. SYED AFTAB OMAR
AlMaarefa College
Objectives
• Describe the morphological characteristics of
each white blood cell.
• Identify the different blood cells in the blood
smear.
• Differentiate between neutrophils, eosinophils,
basophils, monocytes and lymphocytes.
• Describe the functions of each WBCs.
• List the conditions in which their count increases
and decreases.
Apparatus &
materials
 Microscope
 Glass slides
 Lancet
 Alcohol swab
 Leishman’s stain
 Distilled water
Smear Preparation
Types of White Blood Cells
• White blood cells:
• Are leukocytes
•There are five types of WBCs in two categories:
• Granulocytes
• Neutrophils
• Eosinophils
• Basophils
• Agranulocytes
• Lymphocytes
• Monocytes
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Blood smear under microscope
Neutrophils
•Size – 10-14 µm.
•Multilobed nucleus
•Light purple (neutral)
granules
•Other names is
Polymorphonuclear leukocyte
• Phagocytic in function
• Normal range = 50% - 70%
• Elevated in acute bacterial
infections
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Eosinophils
• Size – 10-15 µm
•Coarse red color granules
•Bi-lobed nucleus
• Defend against parasitic
worm infestations
• Normal range 1% - 6%
• Elevated in parasitic
worm infections and
allergic reactions
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Basophils
•Size – 10 – 15 µm
•Bilobed nucleus
•Deep blue granules
covering the whole nucleus
• Release histamine
• Release heparin
• Normal range- Less than
1%
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Monocytes
• Largest of all blood cells
•Size – 12 – 20 µm
•Spherical, kidney-shaped,
oval or lobed nuclei
•No visible granules
• May leave bloodstream to
become macrophages
• Normal range - 2% - 10%
• Phagocytize bacteria, dead
cells, and other debris
•Increase count – in chronic
infections eg. Tuberculosis
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Lymphocytes
•Size – 7-9 or 10-15 µm
•Slightly larger than RBC
• Large spherical nucleus
surrounded by thin rim of
cytoplasm
•No visible granules
•Normal range -20% - 40%
•T cells and B cells
• Both important in
immunity
• B cells produce antibodies • Increased count is seen
•T cells involved in cell
in viral infections,
mediated immunity
chronic infections
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Counting directions
Counting 100 cells
N
N
M
N
N
N
N
N
N
L
N
N
N
E
L
N
Neutrophil =
%
Eosinophil =
%
Basophil=
%
lymphocyte =
%
Monocyte =
%
WBC count decreases in bone marrow suppression due malignancy, radiation,
chemotherapy or any genetic disorder
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