Why CD4 goes down while CD4% goes up (ABSOLUTE CD4 COUNT VERSUS CD4%, 2009)
Hi Dr. Bob, it is a real pleasure to read your answers full of help, professionalism, generosity and fun. I started therapy at an absolute CD4 of 405 and 26% and VL above 100k, I started Atripla six months ago after the first three months my CD4 went up to 625 and 42% and VL went undetectable, but on my recent test (another three months) my CD4 came down to 460 (less 175) while my CD4% went up to 48% (+6%) and still VL <40 (my WBC went down while my Lymphocytes went up in absolute numbers and about 8.5% up). I am wondering how and why this could happen? Is there something wrong going on that I should I worry about? How do I need to interpret this change as + or signs? Will my CD4 rise again? Other than that I feel great. Sorry about asking so many questions, please give me you valuable feedback; I am expressly asking you that because I love all what you do in this forum.
When it comes to monitoring HIV disease, it's important to look for long-term trends rather than worry about transient swings, especially in absolute CD4 counts. Absolute CD4 counts are calculated from the absolute lymphocyte counts. The absolute lymphocyte count is a subset of the white blood cells (WBC) count. The WBC and consequently the total lymphocyte count can vary considerably, depending on what's going on in the body, not only with HIV but with everything else as well. The CD4% is much less susceptible to these transient swings. The percentage calculation therefore is the more reliably consistent indicator of what's happening with your immune reconstitution. Your trend is looking great both virologically (plasma viral load plummeting from "above 100K" to undetectable in three months) and immunologically (CD4% persistently rising). The long-term trend of your absolute CD4 count will follow your CD4%, despite this transient divergence. Nothing is "wrong" and you should not worry about this one test result. You feel great and your combination antiretroviral regimen is performing well! I see nothing but good news! I'll reprint some information from the archives that reviews CD4% compared to absolute CD4 counts.
Be well. Stay well.
CD4 counts vs CD4 percentage (ABSOLUTE CD4 COUNT VERSUS CD4%, 2008) Oct 6, 2008
Dr. Frascino, I am a little new to dealing with HIV. I was diagnosed about 9 months ago. I was wondering what the CD4 percentage was. Because my CD4 count had changed from 510 to 409 in a three month period but the CD4 percentage had risen by 1%. I'm just a little confused by the test results.
Thanks, College guy
Response from Dr. Frascino
Hey College Guy,
I'll reprint below some information about absolute CD4 cell counts and CD4%. The CD4% is the more accurate test, as it is less susceptible to variations related to concurrent phenomena (diurnal variation, other infections, etc.) That your CD4% has risen by 1% is more significant than your decline in absolute CD4 cell count from 510 to 409. Continue to monitor your counts and you'll eventually see more consistent trends.
Absolute CD4 count down while CD4% up. (ABSOLUTE CD4 COUNT VERSUS CD4%) Apr 23, 2008
Hello Dr. Bob,
You are wonderful and doing very important job :) . I have never seen such a Doctor who has an excellent sense of humor and plays the piano. Btw, I play the cello :) .
Now my question. My time of infection is between 2006 02 and 2006 09. I am a gay man and I was infected from unprotected oral sex. I have never done bb. Really!
I am not on meds and my numbers and the following:
2007 01 04. CD4 310, CD4% 29, VL263000.
2007 04 04. CD4 342, CD4% 24%. VL was not measured.
2007 09 01. CD4 717, CD4% 32%. VL was not measured.
2008 04 01. CD4 510, CD4% 35. VL was not measured.
My CD4 has declined from 717 to 510 while CD4% has increased from 32% to 35%. Could you explain this?
My doctor explained me that it is nonsense to look at CD4%, because absolute CD4 count is the only reliable measure. Is it true?
The doctor always refuses to test my VL and explains that is to expensive for the clinic. (I do not live in the USA).
Is it very important to measure VL? Is it enough to measure CD4?
Thank you very much!
Response from Dr. Frascino
I strongly disagree with the advice your doctor gave you regarding absolute CD4 counts versus CD4%! I reviewed this topic in detail recently in this forum. Consequently, rather than retyping the same information, I will instead repost the question and my response from the archives. (See below.)
Next, is it important to measure HIV plasma viral load? Yes, I feel it is very important, as it is the critical piece of information that allows us to measure how effectively our antiretroviral drugs are performing in suppressing HIV replication. It also alerts us as to when and if drug resistance develops.
I would strongly suggest you consider switching to a more competent HIV specialist! He doesn't need to know how to play the piano or cello, but he certainly does need to understand the importance of CD4% and HIV plasma viral load!
%CD4 - What does this mean? Apr 2, 2008
My viral load is 6,000 copies/ml and my CD4 is 594. Based on the above, I have some time to go before I start my meds.
However, my %CD4 is 20%. It was 19% 3 months ago. What does this mean? I am told that the a normal reading is 26-40%. Is there a cause for concern? Thank you.
Response from Dr. Frascino
I see it's time for a review of what CD4 cells are and how we monitor them in HIV infection. So beginning with the basics, a CD4 cell is a type of lymphocyte, which in turn is a type of white blood cell. CD4 cells (also called T-cells) are an integral part of the body's immune system. HIV specifically infect CD4 T-cells by actually becoming part of the cell and using the cell's machinery to make lots of new copies of HIV, which then go out and infect more CD4 cells. Clever, eh? However, the HIV-infected CD4 cells eventually die, which is not so clever, because as HIV wipes out CD4 cells, the immune system is weakened and the HIVer eventually becomes sick and dies. There are millions of different types of CD4 cells and each one is specifically designed to fight a specific type of invading germ. As these cells get wiped out, we lose the ability to fight certain infections and become more likely to acquire "opportunistic infections" that wouldn't normally affect or bother someone with a normal immune system (normal CD4 count). You can think of opportunistic infections as taking advantage of an "opportunity." The opportunity provided by our depressed or deficient immune system allows these germs to do us harm.
The absolute CD4 cell count bounces around significantly, as it is influenced by a number of factors, including time of day, stress/fatigue levels, non-HIV concurrent infections, etc. Infections have the largest impact on CD4 cell counts. Whenever your body fights any infection, the number of white blood cells goes up and consequently the number of CD4 cells rises as well. Vaccinations can also cause this same effect. That's why it's best not to check your CD4 cell count until you've completely recovered from an infection.
Absolute CD4 cell counts are reported per cubic milliliter of blood. (The normal range varies somewhat from lab to lab, but is usually around 500 to 1,600. Because CD4 counts are so variable, we often prefer to monitor CD4 percentage, the percentage of total lymphocytes comprised by CD4 cells. For example, if your CD4% is 20%, one out of five lymphocytes is a CD4 cell. This percentage is more stable than the absolute number of CD4 cells, as it is less affected by the factors mentioned above. The normal range is usually 20% to 40%. A CD4% below 14% indicates severe immune deficiency and is a criterion for the AIDS diagnosis, as is an absolute CD4 count below 200.
I know that may be more information than you wanted, but I wanted you to get your money's worth! Oh, that's right, this is a free service available to one and all!
Be well. Stay well.