Confused by labs and what the differences are CD3/CD4/CD8, etc


I am confused about how to read my labs, and my doctor always just says "they're fine", but I want to understand them better. He always speaks of just "cd4" but there is no cd4 count by itself on my lab test. Which title is actually my Tcell total that they use to define AIDS vs HIV (under 350, correct?)? Is it the CD3/CD4 Absolute? It's very confusing. I understand that I currently have very good labs, but I want to know how to read them, and I am frustrated because all internet searches talk of "CD4" only, and yet my lab tests have no CD4 line without other types combined. Here are my most recent results: CD3+ Absolute: 3742 CD3+ Percent: 87% CD3+/CD4+ Absolute: 2204 CD3+/CD4+ Percent: 52% CD3+/CD8+ Absolute: 1464 CD3+/CD8+ Percent: 34% CD4/CD8 Ratio: 1.51 Viral Load: Not-Detected

Thank you.


I do agree with your doctor's assessment of your overall status. However, some additional explanation is in order. Without getting too techie, we measure blood lymphocytes (a type of white blood cell in your blood) by labelling the cells with fluorescent dye markers to allow us to count them in a machine. CD3+ cells are all T-lymphocytes, which includes both CD4+ and CD8+ lymphocyte cells. These are the major cell involved in your immune system response to HIV. When your result reports CD3+ cells, that number includes all T lymphocytes. In order to count CD4+ or CD8+ cells you have to use two dye markers. That is why in your report a CD4 count is stated as CD3+/CD4+ cells. In general, the number or absolute count of CD4 + CD8 cells should almost equal the CD3 cells, but as you can see there are a few more CD3+ cells over and above CD4+CD8, and that reflects some other cells types. The percent is just the percent of each cell type of all lymphocytes in the blood. I hope this helps clarify it for you. If not, send me another note.