CD4 count measures a protein found in white blood cells that helps the body fight infections. It is used to monitor HIV progression and immune system health, with a count below 200 indicating AIDS. Results can vary and should be interpreted over time.
A CD4 count is the measured level of a certain type of protein, which is often found in certain types of white blood cells. CD4 stands for “cluster of differentiation four” and is an important component of the body’s ability to mount an immune response to a potential infection. A CD4 count can also refer to the specific laboratory work that is done to determine its level, as a routine part of treatment for someone with human immunodeficiency virus (HIV), which can lead to acquired immune deficiency syndrome (AIDS). .
Each time a person visits their HIV specialist, a CD4 count will be taken to determine, at a glance, the state of their immune system. CD4 is often present in T cells and other cells that form and coordinate the body’s immune system. The HIV virus can take over and use these cells to make copies of itself, which then go on to use other immune cells to make more copies. For a while, the body can replace T cells at a fast enough rate to combat this pattern. With proper treatment, this time period can be significantly extended, but the CD4 count is closely watched as an indicator of HIV progression.
As HIV progresses, a person’s CD4 count will decrease more and more, indicating that the presence of the virus is stronger. Count results are usually expressed in the number of cells per microliter of blood, an amount that is about the size of a pea. A person who does not have HIV will normally have more than 750 T cells in this amount of blood. Someone who is HIV positive is considered to have a normal CD4 count if this number is around 500 in the same amount of blood. If this number is lowered below 200, this will be an indication of severe immune damage.
A count below 200 is the threshold beyond which a person is medically defined as having AIDS, rather than simply being infected with HIV. The CD4 count, while important, also varies widely. For example, a person’s CD4 is usually higher in the evening than in the morning and can be affected by the presence of an acute illness such as the flu. Even simple stress and fatigue can affect your results. Thus, CD4 counts are useful over time in determining a pattern of immune system health, but the variability in this number over even a single day should be taken into consideration when interpreting these test results.
Protect your devices with Threat Protection by NordVPN