The CD4 percentage (CD4%) is the percentage of white blood cells (lymphocytes) that are CD4 cells.
The immune system contains lots of different cells. The two main types of lymphocytes are T cells and B cells. CD4 cells are a type of T cell. So the CD4% looks at the CD4 count in relation to other immune cells.
CD4% is sometimes a more stable indication of whether there has been a change in the immune system. If the percentage hasn’t changed the change in the absolute count is not important.
The normal range for HIV-negative adults is 30% to 60%; people with HIV often have a lower percentage. A percentage below 14% indicates an AIDS diagnosis. CD4 percentage, rather than CD4 count, is used to monitor disease progression in children.
CD4% is sometimes a more stable indication of whether there has been a change in the immune system. If the percentage hasn’t changed the change in the absolute count is not important.
- A CD4% of 12-15% is about the same as a count of under 200 cells/mm3.
- A CD4% of 29% is about the same as a count of over 500 cells/mm3, but there is a wider range for higher values.
- The average normal CD4 percentage for someone who is HIV negative is about 40%. The normal range is anywhere from about 25% to 65%.
The CD4% count is also used to monitor children under 12 years old. This is because babies are born with very high CD4 levels. A baby can have a CD4 count that is 3000 cells/mm3.
% CD 4 Pos. Lymph.
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