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Are We Still Just Guessing?

Jun 25, 2005

Good morning Doctor,

Thanks for this very helpful and anonymous site.

I am now at 2 1/2 years off meds. I have been part of a study group since my seroconversion just over 5 years ago. This is my third and longest supervised interruption. The previous two only lasted 10 weeks each.

I have a question about the V/L tests currently being used. The PCR and the NASBA. How can they both be legitimate when they render different results from the same patient and the same blood draw? Quite accidentally the wrong test was used for my last blood draw and bore a V/L count of 29,000. When they discovered they used the wrong test, they ran the alternate test with the same blood which bore a V/L count of 9,000. This result was presented to me with a Youll be happy to hear that. Can you help me understand this disparity? Can you also help me understand why I should be happy to hear, or give more weight to the second result than the first, knowing that both are legitimate? Logic shouts that if the tests are both correct, then they are also both incorrect. This leaves me, the patient, without a point of reference. It also makes me wonder if any of these numbers really mean anything.

For the last 6 months I have been eating poorly, exercising less and smoking more. In short, my temple is a mess. Yet, according to the results of the correct test, my Ts climbed and my V/L dropped by 20K. This makes no sense to me. The results of the wrong test make more sense in the cause & effect world.

Can you help me to understand how I can use these numbers to manage my HIV infection? Or, can you direct me to a site that can? Isnt there a HIV for Dummies out yet? Or are these numbers meaningless and are we still just guessing?


Response from Dr. Holodniy

Both tests measure the same thing, plasma level of viral load. However, they use different technologies and as a consequence will have have different viral load results. That said, those results are really not that different. With most of the technologies, a 3 fold or 3 times difference would be considered assay variability regardless of the assay used. Thus, these numbers are meaningful, measure the same thing although somewhat differently, and because of assay variability are relatively close in terms of results. The most important point is stick with the same assay type and the results will always be more consistent.

Behavior of the hiv vrius
Where are the Medicines with Less Side Effects?

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