Complete Blood Count, commonly
known as CBC, is a routine blood
test used to evaluate a patient's
overall health status. It is one of
the most common laboratory tests
performed to diagnose and monitor a
wide range of medical conditions,
such as infections, anemia,
leukemia, and other blood
disorders. The CBC provides
important information about the
various components of the blood,
including red blood cells, white
blood cells, and platelets. In this
guide, we will explore what a CBC
is, what it measures, and how to
interpret the results.
What is a CBC?
A CBC is a blood test that measures
the levels of various components of
the blood, including red blood
cells, white blood cells, and
platelets. The test is usually
ordered as part of a routine
medical exam, but it can also be
used to diagnose a wide range of
medical conditions.
What does a CBC measure?
A CBC measures the following
components of the blood:
-
Red Blood Cells (RBCs)
RBCs are responsible for carrying
oxygen from the lungs to the body's
tissues and transporting carbon
dioxide back to the lungs. The CBC
measures the number of RBCs in the
blood, as well as their size and
shape.
The normal range for RBCs in men is
4.5-5.5 million cells/mcL
(microliter), while in women, it is
4.0-5.0 million cells/mcL. Abnormal
RBC levels can indicate anemia or
other blood disorders.
-
White Blood Cells (WBCs)
WBCs are responsible for fighting
infections and diseases. The CBC
measures the number of WBCs in the
blood and the different types of
WBCs.
The normal range for WBCs is
4,500-11,000 cells/mcL. Abnormal
WBC levels can indicate an
infection, leukemia, or other blood
disorders.
-
Platelets
Platelets are responsible for
helping the blood to clot. The CBC
measures the number of platelets in
the blood.
The normal range for platelets is
150,000-450,000 cells/mcL. Abnormal
platelet levels can indicate
bleeding disorders or other blood
disorders.
-
Hemoglobin (Hb)
Hemoglobin is a protein found in
RBCs that carries oxygen from the
lungs to the body's tissues. The
CBC measures the amount of
hemoglobin in the blood.
The normal range for hemoglobin in
men is 13.5-17.5 g/dL (grams per
deciliter), while in women, it is
12.0-15.5 g/dL. Abnormal hemoglobin
levels can indicate anemia or other
blood disorders.
-
Hematocrit (Hct)
Hematocrit is a measure of the
percentage of RBCs in the blood.
The CBC measures the hematocrit
level in the blood.
The normal range for hematocrit in
men is 38.8-50.0%, while in women,
it is 34.9-44.5%. Abnormal
hematocrit levels can indicate
anemia or other blood disorders.
How is a CBC done?
A CBC is a simple blood test that
is performed by a healthcare
provider. A sample of blood is
drawn from a vein in the arm using
a needle. The blood is collected in
a tube and sent to a laboratory for
analysis. The results of the test
are usually available within a few
hours or a few days.
How to interpret the results of a
CBC?
The results of a CBC can provide
important information about a
patient's overall health status. A
healthcare provider will interpret
the results of the test and use
them to diagnose and monitor
medical conditions.
The following are some common
abnormalities that can be detected
by a CBC: