Question
What is a normal CD4 count, CD4% and CD4:CD8 ratio?
16 January 2018. Related: All topics, CD4 and viral load, Other tests.
Answer
After finding out you are HIV positive, your doctor will run several blood tests.
One will be for your immune system and will include your CD4 and CD8 count. Of these, the CD4 count is the most important main result but the CD4% and CD4:CD8 ratio are also sometimes useful.
This Q&A include information about these cels and about interpreting the test results.
CD4 cells are a type of blood cell that is part of your immune system. They are a type of white blood cell (lymphocyte). CD4 cells are sometimes called T-helper cells or T-cells
There are two main types of T-cells.
- CD4 cells, also called T4 cells, are “helper” cells. They lead the attack against infections.
- CD8 cells, (T8 cells), are “suppressor” cells that complete the immune response. CD8+ cells can also be “killer” cells that kill cancer cells and other cells that are infected by a virus.
CD4 and CD8 counts
The normal ranges for CD4 and CD8 counts vary depending on the lab and test. On average, the normal CD4 range for an HIV negative person is between 460 and 1600. This is an average. Anywhere in this range is good.
Although generally a higher CD4 is good, an HIV negative person with a normal CD4 count of 1200 is not more healthy than someone whose normal count is 400.
The exact CD4 count is not so important. CD4 counts can vary from day to day and even from hour to hour. So the general CD4 result is more important than the exact number.
A normal CD8 range is from 150 to 1000. This test is not used as much but the results come together. It is more important to know your CD4 count than your CD8 count.
CD4 percentage (CD4%)
If you get a CD4 count that is ever unexpectedly high or low, then your CD4% (CD4 percentage) can show whether this is a real change in immune function. The CD4% is a more stable marker than the absolute CD4 count.
The CD4 percentage refers to percentage of total lymphocytes that are CD4 cells. If your test reports CD4% = 34%, that means that 34% of your lymphocytes are CD4 cells.
The average normal CD4% for HIV negative adults is about 40%. However, as with CD4 counts and other test, the range for a “normal” result in an HIV negative person is also wide – from about 25% to 65%.
CD4:CD8 ratio
The CD4:CD8 ratio is also sometimes used, but less often. This is a measure of how balanced your immune function is. This calculated by dividing the CD4 result by the CD8 result.
In HIV negative people, the normal range for the CD4:CD8 ratio is between 0.9 and 1.9. This means that there are about 1 to 2 CD4 cells for every CD8 cell.
When not on HIV treatment, just like the CD4 count and CD4%, the CD4:8 ratio drops over time. Eventually, unless you start treatment, there will be more CD8 cells than CD4 cells (i.e. the ratio drops to less than 1.0).
The CD4:CD8 ratio might be better at predicting future risk in people whose CD4 count is high (above 500 cells/mm3). However, not all studies agree on this.
Other studies have shown that starting ART soon after HIV infection has a much higher chance of keeping the CD4:CD8 ratio higher than 1.0.
Note: this answer was last updated in January 2018 from a post that was originally published in December 2006.
Hi George,
Try not to worry about the ratio. From your results its very clear that you’re doing very well. Your CD4 has risen really well and your viral load is undetectable. This is great.
Hello. I would like to ask what is the effect of CD8 + cells and the CD4 + / CD8 + ratio on the health of the patient being treated.
I am a 48-year-old man, less than a year of HIV +, right from the primacy to ART (Genvoya). At the beginning of VL infection, approximately 4mil and CD4 + 268, at present (after 8 months ART) VL 26, CD4 + 501 and CD4 + / CD8 + 0.29.
According to available information on the Internet, healthy people should have this ratio between 1 and 2. Logically, given the relatively satisfactory CD4 + count, I have a low value for this ratio due to the high CD8 + count. Do you think it is a standard condition at about 1 year after primoinfection? What is it caused? I believe that an optimal ratio of at least about 1 can not be achieved from a 0.29 value only by a gradual increase in CD4+. Can I expect the CD8 + count to decrease over time? How fast? It is true that values of this ratio of about 0.2 are a sign of poor immune function, or AIDS. Does the current value of this ratio of prospects for the long-term success of treatment (keeping the virus below the level of detectability) predict in the future? I am sory for my wrong English.Thank you very much for your answer.
Hi Nancy,
This is great news. It means that you’re doing well and that your immune system is much stronger. This will be due to the medication that you’re taking.
Hi, I’m diagnosed with HIV in 2016 and my CD4 count was 336 and now its 636, what does it mean?
Hi Buzabani,
Its now recommended that everyone who is positive should be on meds. This includes people like yourself who have high CD4s. Therefore, if you’re ready, then yes you should start. For more info about starting meds, please see here:
http://i-base.info/guides/starting
My CD4 is 548, do I need to take meds?
Hi Sims,
What was your CD4 when you were diagnosed? What is it now? If the drop is slight it could be a simple blip. These are common. For more info please see here:
https://i-base.info/qa/424
Your diet won’t be having an influence on your CD4.
I was dignosed with oesteomylitis and HIV In April 2017 and currently on ART but after 4months now my CD 4 count has dropped but i have since stopped drinking and smoking earlier before i was dignosed,what could be the problem could it be my type of diet
Yes my dear ,in case of any complaint, you need to see yrs doctor, be it cough, venereal disease, reaction of treatment etc
Hi Terri,
i-base is an organisation that works with and for people who are living with HIV. If you are having health problems you will need to talk to a doctor.