T-cell count

What is a T-Cell Count?

A T-cell count is a laboratory test to measure the number of T-cells in the bloodstream. T-cells are a type of white blood cell responsible for the body's immune system and fighting infection.

Why is a T-Cell Count Done?

T-cell counts are usually done to check the health of the immune system. Doctors may order a T-cell count when a person shows signs of a weakened immune system, such as frequent infections. A T-cell count can also be used to monitor HIV/AIDS or cancer treatments.

Preparation for a T-Cell Count

No special preparation is needed for a T-cell count. However, it is important to let the doctor know if there are any medications that may interfere with the test, such as blood thinners.

Procedure of a T-Cell Count

T-cell counts are performed in a laboratory. A blood sample is taken and the number of T-cells is measured using a machine called a flow cytometer. The results are usually available within a few days.

Types of T-Cell Counts

There are three different types of T-cell counts that can be done:

  • Absolute T-cell counts: measure the exact number of T-cells in the blood
  • Relative T-cell counts: measure the percentage of T-cells in the total number of white blood cells
  • T-helper/T-suppressor ratio: measure the ratio of two types of T-cells, T-helper cells and T-suppressor cells

Risks of a T-Cell Count

T-cell counts are a safe and easy procedure with no known side effects. The only risk is discomfort from the needle used to take the blood sample.

When Is a T-Cell Count Done?

A T-cell count is usually done when a person has signs of a weakened immune system, such as frequent infections or HIV/AIDS. It can also be used to monitor cancer treatments.