Managing CBC Services by 3 part differential cell counter

Dr A D Deshpande MD (Micro), MD (Patho)

Cell Counters are every where

3 Part Differential WBCs are counted as 3 Groups

NeutrophilsLymphocytes

E

M

B

5 Part Differential WBCs are counted as 5 Groups

N L E M B

Wallace Coulter

1960 Model

Principle of Cell Counter

Volume of cell is basis of differentiation.

Cells pass in one Line

Cells are bad conductors of electricity

Electrical impedance is proportional to cell volume

RBC chambers – RBCs and Platelets are counted

WBC chamber – WBCs and HB are estimated.

2 – 25 FlPlatelets

30 - 250 flRBCs

>35 fl – WBCs (Separate chamber)

Volume separate them Volume separate them

femtolitre = 10 −15 litres

Report in 2 formats

Numbers Graphs

We always look only

numbers

Don’t ignore me..

Normal Histogram

Platelet Graph

RBC Graph

30 200

Volume of cell

NUMBER

Of Cells

Platelet Graph

RBC Graph

30 200

Giant platelets / Microcytes / Fragmented RBCs

Platelet Graph RBC Graph

30 200

RBC Clumping / Cold Agglutinin / Clotted sample

Platelet Graph RBC Graph

30 200

Macrocytic (Megaloblastic Anemia)

WBC Graph

L PM

Blood indices

MCVMCHMCHC

80 – 100 flNormal range

MCV

MCV80 100

NORMAL

706050 110Iron deficiencyThalassemia Anemia. of chronic disorders

B12 & Folic acid deficiencyLiver disease

MCH27-32 pgmNormal range

MCHC

32-36 %

Red cell Distribution Width

(RDW)

Rule of 3

RBC count X 3 = Hemoglobin %

Hemoglobin % X 3 = Hematocrit

Hb 7.4 gm %

MCV 65 fl

MCH 18 pgm

RDW 19

Low HbLow MCVHigh RDW

Low HbLow MCVHigh RDW

This can be seen in Anemia due to chronic disorders

Serum Iron Serum Ferritin TIBC % Saturation

Low HbLow MCVNormal RDW

Hb 8.2 gm %

MCV 105 fl

RDW 18

Low HbHigh MCVHigh RDW

Hypersegmented Neutrophil

Hb 9.1 gm %

TLC # # # # Platelet count 24,000 / cmm

Acute Leukemia

What else we can see in PS

Malarial Parasite

Sickle Cells

WBC Counts

LeukopeniaAplastic anemiaChemotherapyMalariaTyphoidDengue

<4000 WBCs / cmm

Leukocytosis

>11,000 WBCs / cmm

NeutrophilsBacterial infection

Trauma, Burn, SurgeryMyocardial infarctionMetabolic acidosisPregnancy

LymphocyteAcute viral infections – Infectious mononucleosis, hepatitis, cytomegalovirus infectionTuberculosisCLL

Eosinophilia Allergy –

Asthma, Urticaria, Rhinitis

Parasites – Filaria,

Trichinosis, Tropical

eosinophiliaEczema,

Dermatitis

Platelets

Normal range

1.5 Lakhs – 4.5 Lakhs/cmm

Thrombocytopenia (common causes)

Falciparum malariaDengueHIVLeptospiraMegaloblastic anemiaDrug induced

Errors in Platelet count

Take home message

• Numerical data + Graphs Important

• PS exam is mandatory• MCV MCH & RDW are useful • Advise necessary further

investigations - Iron studies , Hb electrophoresis

Thank you