Full Blood Count

A full blood count (FBC) measures the numbers of the different types of blood cells. Common reasons for having the test include suspected abnormalities of: red blood cells (e.g. anaemia); white blood cells (e.g. infections, cancers such as lymphoma and leukaemia, and immune suppression such as HIV/AIDS); and platelets (e.g. some cancers and drug side-effects). Blood is withdrawn from a needle inserted into a vein, usually in the area inside the elbow, and sent for laboratory analysis.

What is it?
Full blood count (FBC) is a test that measures (counts) the numbers of the different types of blood cells (red blood cells, white blood cells, platelets).

It is a simple, and commonly performed test. The blood can be drawn at your doctor’s rooms, a clinic, or in hospital. The analysis is done in a laboratory..

Why is it done?
A FBC is done when an abnormality in the numbers, and/or types of, blood cells is suspected. There are a great many reasons to perform this test but some of the more common indications include:

• Red blood cells: Anaemia (shortage of red blood cells and decreased oxygen carrying capacity, which causes fatigue).
• White blood cells: Infection (increased white cells), certain cancers like lymphoma and leukemia (increased, but abnormal, white cells), immune suppression e.g. HIV/AIDS (decreased white cells).
• Platelets: Certain cancers (increased platelets and increased blood clotting), drug side-effects (decreased platelets and increased bleeding tendency).

What happens?

Before – how to prepare
No special preparation is needed.

During – how the test is done
A convenient area, where there are prominent veins, is identified and cleaned – the area inside the elbow is often used. A tourniquet or tight band is applied above the area in order to increase pressure and dilate the veins. A needle is then inserted, through the skin, into a vein, and some blood is withdrawn. The needle may cause some pain but this is not usually severe. The blood specimen is sent to the laboratory for analysis..

After the test
You will have a small dressing over the puncture wound, which can be removed after a few hours.

Risks and Compilations
There is a slight risk of excessive bleeding at the puncture site and an even smaller risk of infection.

Short Description
A full blood count (FBC) measures the numbers of the different types of blood cells.

Keywords
full blood count, FBC