Blood cell count

Blood cell count (RBCs,
WBCs, PLTs and DLC)
Hussein A. Abid 
Lectures: 5-7
Middle Technical University
Technical Institute of Baquba
Medical Laboratory Technology Department
Academic year 2019-2020 – Spring semester
Medical Laboratory Technology & Quality Control Applications
Module code: MLT113
L.No.: MLT113-20-T-05-07

Blood cells count
• Human blood cells are:
1. Erythrocytes (Red Blood Cells, or RBCs)
2. Leukocytes (White Blood Cells, or WBCs)
3. Thrombocyte (Platelets, or PLTs)
• Blood cell counting is needed to assess the cell
number and function, which in turn leads to treat
possible disease.
01 Hussein Adil Abid - 2020

Blood cells count
• Red blood cells: are the most common type of blood cells and
the principal means of delivering oxygen (O2) to the body
tissues via blood flow through the circulatory system.
Hemoglobin found in its cytoplasm.
• White blood cells: are a central part of the immune system.
They help to protect the body against foreign substances,
microbes, and infectious diseases. There are 5 types of WBCs:
neutrophil, eosinophil, basophil, lymphocyte, and monocyte.
• Platelets: are tiny blood cells that help your body form clots to
stop bleeding.

Blood cell count
• The apparatus for counting blood cells is called a
haemocytometer and consists of:
 counting (Neubauer) chamber
 cover glass
 pipettes
 rubber tube with a plastic mouthpiece for drawing the
fluid into pipette.
 slide & stain if it is required.

Haemocytometer
Haemocytometer Counting chamber

Dilution
• Dilution of blood sample is necessary before counting
because it contain large number of cells.
• Dilution is performed using a diluting fluid.
• Manually, TWO types of dilution could be used:
1. Dilution pipettes (provided with hemocytometer)
2. Bulk dilution (using pipette and its tip)

Bulk dilution
RBCs count:
• Dilute the sample (1:200): add 20 μl of blood to 4 ml of
diluting fluid
• Dilute the sample (1:20): add 20 μl of blood to 400 μl of
diluting fluid
PLT count:
• Dilute the sample (1:20): add 20 μl of blood to 4 ml of
diluting fluid

Diluting fluids
PlateletsWBCsRBCs
1% ammonium oxalate
solution (1 g of
ammonium oxalate
powder dissolved in 100
ml of DW and then
filtered and stored in
refrigerator)
1. Turk’s solution (1%
glacial acetic acid
[destroys RBCs] +
gentian violet stain
[stains WBCs]
2. Toisson’s fluid (This
solution tinted with
methyl violet [to give
a purple colour.
1. Hayem’s solution
2. Physiologic saline
(0.8%)
3. Toisson’s fluid
4. Formal citrate

Materials needed
• Syringe
• Cotton
• 70% isopropyl alcohol
• Tourniquet
• EDTA tube
• Plain tubes
• Pipette and tips
• Microscope
• Improved Neubauer Chamber
• Coverslip
• Petri-dish for PLT counting
for blood collection

Procedure
1. Early morning, the bench should be cleaned carefully and
safety procedures should be applied.
2. In a rack, put a suitable volume of diluting fluid in clean
and dry plain tubes (4 ml for RBCs and PLT tubes & 400
μl for WBCs tubes).
3. Once the blood sample is received, put it on haemomixer
for 5 minutes to be mixed thoroughly.
4. Using a pipette, transfer 20 μl of well-mixed blood and
mix it with the diluting fluid (according to the test needed).
5. Leave the mixture away, for the cells to be settled for 5
min.

Procedure
1. Early morning, the bench should be cleaned carefully and
safety procedures should be applied.
2. In a rack, put a suitable volume of diluting fluid in clean and dry
plain tubes (4 ml for RBCs and PLT tubes & 400 μl for WBCs
tubes).
3. Once the blood sample is received, put it on haemomixer for 5
minutes to be mixed thoroughly.
4. Using a pipette, transfer 20 μl of well-mixed blood and mix it
with the diluting fluid (according to the test needed) for 3 min.
5. Deposit a tiny drop on the sloping polished surface of the
counting chamber next to the edge of the cover glass.

Procedure
A) In case when the RBCs/WBCs are counted, leave the
chamber away for 5 min, for the cells to be settled for 5
min.
B) In case of PLTs are counted, place the hemacytometer on
moistened filter paper in a Petri-dish, and allow to stand 10
minutes to permit the cells to settle and the solution not to
get dried through this time.
6. Carefully, place the hemacytometer on the microscope stage
and begin with power 10X and then focus.
7. Calculate the RBCs & PLTs (in 5 squares) and WBCs (in 4
squares) as the figure on the next slide.

W: to count WBCs
R: to count RBCs & PLTs

Through cell counting, two sides should included and two should not

Calculations
RBCs equation:
• RBCs (cell/c.c.) = N × 10,000
N: total RBCs number in the 5 squares
• WBCs (cell/c.c.) = N × 50
N: total WBCs number in all the 4 squares
PLT count:
• PLTs (platelet/c.c.) = N × 5,000
N: total PLTs number in the 5 squares of both sides ÷ 2

15
Normal ranges of blood cells count
Hussein Adil Abid - 2020
PLTs (plt/mm3)WBCs (cell/mm3)RBCs (106/mm3)
150,000 - 450,0004,500 – 11,000
Male:
4.7 – 6.1
Female:
4.2 – 5.4
Normal range
ThrombocytosisLeukocytosis
Erythrocytosis (or
polycythemia)
Term of 
ThrombocytopeniaLeukocytopenia
Erythrocytopenia
(or anemia)
Term of 

Possible interpretations
• Erythrocytosis:
 Smoking, high altitudes, cardiovascular disease, polycythemia
• Erythrocytopenia:
 Anemia, alcohol abuse, hemorrhage, leukemia,
• Leukocytosis:
 Pathologically: acute infections like pneumonia, tonsillitis,
appendicitis, etc.
 Physiologically: pregnancy and newborn.
• Leukocytopenia:
 Certain diseases such as mumps, small pox, typhoid fever,
malaria,..
 Side effect of some drugs such as aspirin, sulpha drugs, etc….
 Diabetes Mellitus

Possible interpretations
• Thrombocytosis:
cancer chemotherapy, disseminated intravascular coagulation
(DIC), hemolytic anemia, hypersplenism, idiopathic
thrombocytopenic purpura (ITP), leukemia, massive blood
transfusion, thombotic thrombocytopenic purpura (TTP), celiac
disease, vitamin K deficiency
• Thrombocytopenia
 chronic myelogenous leukemia (CML), polycythemia vera, primary
thrombocythemia, recent spleen removal.

GranulocytesAgranulocytes

19
Differential Leukocyte Count (DLC)
Hussein Adil Abid - 2020
NeutrophilsEosinophilsBasophils
40 – 602 – 40.5 – 1Normal (%)
4000-7000 cells/mm3<450 cells/mm315-100 cells/mm3Absolute number
NeutrophiliaEosinophiliaBasophiliaTerm of 
NeutropeniaEosinopeniaBasopeniaTerm of 
LymphocytesMonocytes
20 - 403 – 8Normal (%)
1000-4000 cells/mm3<850 cells/mm3Absolute number
LymphocytosisMonocytosisTerm of 
LymphocytopeniaMonocytopeniaTerm of 

Leukocytosis
Possible causes of increaseTerm
Bacterial infection, burns, stress, diabetic acidosis,
hemorrhage.
Neutrophilia
All chronic infections such as syphilis, viral infections.Lymphocytosis
Parasitic infestation, allergic conditions (bronchial
asthma, hay fever).
Eosinophilia
Hemolytic anemia, irradiation, chicken poxBasophilia
Malaria, spotted fever, bacterial endocarditic, typhoid
fever, viral or fungal infection, TB.Monocytosis

Leukopenia
Possible causes of decreaseTerm
Exposure to radiation, drug toxicity, vit. B12 deficiencyNeutropenia
Acute TB, stress, aplastic anemia, infectious hepatitis,
Drug toxicity
Lymphocytopenia

Blood cell count

Recommandé

Recommandé

Contenu connexe

Tendances

Tendances (20)

Similaire à Blood cell count

Similaire à Blood cell count (20)

Plus de Hussein Al-tameemi

Plus de Hussein Al-tameemi (20)

Dernier

Dernier (20)

Blood cell count