CD4 and CD8

Print this article
Share this page:
Also known as: T4 count; T-helper cells; T-suppressor cells; cytotoxic T-cells
Formal name: CD4 lymphocyte count; CD8 lymphocyte count; T-cell subsets; CD4/CD8 ratio; CD4 percent
Related tests: HIV antibody, p24 antigen test, HIV viral load, HIV genotypic resistance testing, HIV phenotypic resistance testing

At a Glance

Why Get Tested?

Most often, this test is done to measure the strength of your immune system if you’ve been diagnosed with HIV infection.  Occasionally it may be used with other conditions.

When to Get Tested?

If you’ve been diagnosed with HIV, soon after you are first diagnosed to get a baseline assessment of your immune system; 2-8 weeks after starting anti-HIV therapy and then every three to four months if you continue therapy

Sample Required?

A blood sample taken from a vein in your arm

Test Preparation Needed?

No test preparation is needed.