CD4+ Cells

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Overview

A CD4+ count is a blood test to see how well the immune system is working in people who have been diagnosed with HIV. CD4+ cells are a type of white blood cell. White blood cells are important in fighting infections. CD4+ cells are also called T-lymphocytes, T-cells, or T-helper cells.

HIV infects CD4+ cells. The number of CD4+ cells helps determine whether other infections (opportunistic infections) may occur. If HIV isn't treated, CD4+ counts generally go down as HIV gets worse. In most cases, a low CD4+ count means you have a weakened immune system and a higher chance of getting opportunistic infections.

Why is a CD4+ count done?

CD4+ counts are done to:

  • Keep track of how the HIV infection is affecting your immune system.
  • Help diagnose AIDS. If you don't get treatment, HIV infection can progress to AIDS.
  • Check to see if you're at risk for other infections (opportunistic infections).
  • Decide whether to start treatment to prevent opportunistic infections, such as medicines to prevent Pneumocystis pneumonia.

How often your CD4+ count is checked depends on your treatment, your health, and your prior CD4+ count results.

Credits

Current as of: May 13, 2023

Author: Healthwise Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

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