Hello Doctor,

I had attained continuous undetectable viral loads while on Atripla for around 4 1/2 years, and then 4 months ago (May 2009) it went up to 2920, but a few days ago (September 2009) it's gone back to <48. I felt very discouraged after that detectable result, as I've never missed a dose, not even once, although sometimes my dosage times would vary by a few hours. Previously, until the late 1990s, I'd taken AZT, DDI, DDC, and 3TC in various combinations as dual therapy while attaining imperfect suppression. I was tested for resistance in 1998 and it was found that I had 184V, the one for 3TC, but apparently nothing else. Then I was completely off medications for around 7 years because I was out of the country and did not have access to medical care. While on therapy in the 90s my CD4 was around 500-730.

Without any further resistance testing, in the US again, I was then started on Atripla in January 2005, with a CD4 of 210 and viral load of around 40,000. For the last 4 years I have been a graduate student and I tend to always get my HIV tests at the very end of the semester when I feel utterly run down from overwork. When I had that blip four months ago I was getting a cold, if I remember correctly. On that occasion, my CD4 went down to 503 from 684 five months before that (January 2009).

So, in the upshot, I'm pleased that I've returned to <48, with CD4 now at 655, but I'm becoming worried about whether this blip is presaging some sort of weakening of my ARV therapy. The doctor had ordered a resistance test at the time of the September 2009 visit, but since I have returned to undetectable I suspect we won't get a result.

What do you think? Is this blip just the harmless effect of feeling transiently ill, or a lab error, or incipient resistance? And if this is an early harbinger of resistance, should I be thinking in terms of bolstering the Atripla with some additional HIV med while it's currently undetectable? How high can a detectable result normally go after longterm undetectable results, in the setting of perfect adherence? In your own experience, what's the highest you've ever seen for a viral load that went back to undetectable without a change in therapy? I really like my Atripla--it's like an old friend--and I'd like to stay with it as long as I can.

Thanks for you advice.

Hello and thank you for your post.

If your viral load returned to undetectable following a detectable value, then it's certainly a blip.

Admittedly, a value of 2900 raises questions and concerns- but perhaps there were other causes-- ie., lab error, transient infection or immune stimulation (eg., sinus infection, vaccination.) I usually think of blips as values less than 1000. Certainly a test of 10,000 would raise significant concerns.

I would have preferred to have a confirmation of the 2900 viral load within weeks (and weeks without other issues as noted above)- a resistance test would definitely be in order if the repeat test confirmed a viral load greater than 500-1000 copies.

So, at this point, I wouldn't view the past as a necessary harbinger of resistance and would continue to stay as adherent as possible to your current treatment.

I hope this helps. Be well and stay in touch.

BY