Understanding CD4 Counts
Aug 31, 2010
Is there a reason why CD4 counts fluctuate? I have been enrolled in a phase III clinical trial for the "quad" for 8 weeks. At the start my viral load was at 4,000+ copies and my CD4 was around 620. Within 2 weeks my viral load was undetectable and my CD4% has gone up from 30% to 37% however my CD4 has dropped to 377. It seems like a big drop to me and the researchers didn't seem concerned unless it drops below 300 - but I would think CD4 counts would go up - not down. So are the factors or reasons why this particular number has dropped or why CD4 counts fluctuate. Thanks.
Response from Dr. McGowan
Thanks for the question. CD4 cells are distributed throughout the body...in the blood, lungs, heart, intestines, brain,etc. Infact the vast majority of all CD4 cells are out in the tissues, not floating in the blood. They can find and attack infection best at the source in the tissues of the body. However, we only measure CD4 counts in the liquid part of the blood....so in essence we are looking only at the tip of a very large iceberg. As that iceberg bobs in and out of the water the amount we see goes up and down. That is, as the CD4 cells move in and out of the blood to the tissues the number can fluctuate (even from morning to night). The CD4% can be more stable since the proportion of T cells that are CD4 is consistent between what is in the blood and tissues (just like the content and makeup of the part of the iceberg above and below the water line). Good luck on tyhe QUAD trial you have had a very good initial response.
Get Email Notifications When This Forum Updates or Subscribe With RSS
This forum is designed for educational purposes only, and experts are not rendering medical, mental health, legal or other professional advice or services. If you have or suspect you may have a medical, mental health, legal or other problem that requires advice, consult your own caregiver, attorney or other qualified professional.
Experts appearing on this page are independent and are solely responsible for editing and fact-checking their material. Neither TheBody.com nor any advertiser is the publisher or speaker of posted visitors' questions or the experts' material.