Complete Blood Count (CBC)

choppedspleenMechanics

Feb 21, 2014 (3 years and 6 months ago)

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Clinical pathology:

Complete Blood count

GENERAL OBJECTIVE
:


After finishing lab activity of CBC, the
student will be able to describe the CBC in
the DMS case problem

SPECIFIC OBJECTIVE
:


At the end of lab activity of CBC , the
student will be able to interprete:


-

the normal of CBC


-

the abnormal of CBC

Complete Blood Count (CBC)


Providing important information about the kinds
and numbers of RBC, WBC and platelet.


Being part of routine physical examination



Help :


To evaluate symptoms (weakness, fatigue, bruising,
fever, or weight loss)


To diagnose conditions (anemia, infection)


To diagnose diseases of the blood (leukemia)


To monitor the response to some types of drug or
radiation treatment


CBC usually includes :

1.
WBC count

2.
WBC differential

3.
RBC count

4.
Hematocrit

5.
Hemoglobin

6.
RBC indices (MCV, MCH, MCHC)

7.
Platelet count

8.
Blood smear **

9.
RDW

10.
ESR

CBC can be performed :


Manually :


Hemocytometer


Calculate from other CBC results (RBC indices)


Automatically (hematologic analyzer)

WBC count


To express WBC concentration per unit volume of blood
(mm
3
).


No distinction is made among the six normal cell types
(band neutrophils,segmented neutophils, lymphocytes,
monocytes, eosinophils, basophils).


Increase WBC count


leucocytosis


Decrease WBC count


leucopenia


WBC Differential


5 major kinds of WBC


Immature neutrophil, band neutrophil


include to
the test.


Each type of cell plays a different role in protecting the
body.


Number of each type


give important information
about the immune system.


Expressed as a percentage of each type


Increase/decrease number of each type


help
to
identify :


infection (neutrophilia, lymphocytosis)


Allergic or toxic reaction to certain medication
(eosinophilia)


Malignancy (leukemia)


Hemoglobin


Main component of RBC


Conjugated protein


Serves as a vehicle for the transportation of O
2

and
CO
2
.


Gives blood cell its red color


Hemoglobin test measures the amount of hemoglobin
in blood.


Decrease


anemia

RBC indices

There are 3 RBC indices :

1.
MCV (Mean Corpuscular Volume)

2.
MCH (Mean Corpuscular Hemoglobin)

3.
MCHC (Mean Corpuscular Hemoglobin
Concentration).



Their values are determined from other
measurements noted during CBC

Platelet count


expressed as concentration


platelet cells per unit
volume of blood (mm
3
).


Decrease


thrombocytopenia


Increase


thrombocytosis

RDW


Red Cell Distribution width


Reports whether all the red cells are about the same
width, size, and shape.


This helps further classify the types of anemia.

Erythrocyte

Sedimentation Rate


Measuring the sedimentation of erythrocytes in


diluted human plasma over a specified time period (1 hour)


Measuring the distance from the bottom of the surface
meniscus to the top of erythrocyte sedimentation in a
vertical column containing diluted whole blood.


Not very specific/diagnostic test


still use in many
institutions as a screening test for inflammation

Factors affecting ESR


RBC size & shape


Plasma fibrinogen & globulin levels


Mechanical


Technical


Factors affecting the ESR :

Increase :

1.
Rouleaux formation

2.
Fibrinogen (elevated)

3.
Immunoglobulin
(excess)

Decrease :

1.
Microcytes

2.
Sickle cells

3.
Spherocytes

Methods performing ESR :


Manual :


Westergren Method


Wintrobe Method


Automatic

Normal values :


Adult men


0
-
15 mm/h


Adult women


0
-
20 mm/h

Diseases associating with an
elevated ESR :

1. Chronic infections(Tb)

2. Multiple Myeloma

3. Cryoglobulinemia

4. Temporal arteritis

5. Inflammatory diseases

6. Pregnancy

7. Anemia

8.
Malignant neoplasms

9.
Paraproteinemias

10.
Macroglobulinemia

11.
Hyperfibrinogenemia

12.
Rheumatoid arthritis

13.
Collagen disease

14.
Polymyalgia
rheumatica



Results


Normal value can vary from lab to lab


Normal value for CBC tests varies, depending on age,
sex, elevation above sea level, and type of sample.