sudden rise in VL ( bDNA Assay V Taqman Assay II )

[sam66]

  
   I'm on Atripla, I have adherence of 100% , give or take one hour lateness.
   I have been undetectable for over one year; but on my last blood test on 29/07/09 my vl  had
   gone up to 104.
    so two weeks later hospital called me to come in for another test, they told me not to worry.
    Today I had my appointmet with my specialist. He informed me result of the second test.

    Again detectable VL=94,

    Then he informed me the hospital recently changed the VL test.  The old test was the
     bDNA Assay. But now they have switched to Taq man Assay II.
     He said quite a few other patients had the same sort of results. His advise Waite 3 months and
     test again, which I'm happy to do.

     I'm in North LONDON.
     Has anyone  had a similar experience recently ?

      Also I found this, which is interesting.    
    
     http://blogs.jwatch.org/hiv-id-observations/index.php/2009/03/04/taqman-hiv-rna-assay-be-careful-what-you-wish-for/

[newt]

Yes the blog link is informative, and this is a known problem ie over-sensitivity on some tests. In truth, several close-together viral load measurements will give a sawtooth shape - up and down - and this particular test will reveal this fact more fully - but the trend on average will be a very low viral load.

The draft for the next British HIV Association guidelines on routine monitoring of HIV abandons the notion of under 50 copies and say clinics must decide the lower limit of results they want reported, for exactly the reason that some very new tests are, ahem, too sensitive and detect all sorts of dead HIV particles, increasing viral load. I wouldn't worry unless on the next two tests the trend is up towards above 200 and beyond.

- matt

[sam66]

 

     Thanks Matt,   reassuring
     
                 interesting about dead HIV can be detected, what hapens to them, do they just wether away like any other dead cell, and get flushed out by the body.

    sam

[newt]

The short answer - the dead crap gets eaten or excreted.

The long answer - HIV only "lives" (subsists really, since viruses don't really live like worms or bacteria) in a dynamic form in a cell.

When it's outside a cell it's a neatly packaged set of protein strings ready to do some dirty work, but more or less static. Like a bomb waiting to go off.

When HIV gets into a cell it starts reproducing, using the cell's genetic structures to help, as scaffolding in fact (our cells are so helpful).

When an infected cell dies the virus is broken into many, very distinct pieces as the cell disintegrates. From the body's point of view the cell and its extra payload are waste.

Broken bits of HIV are deemed alien debris by our immune system. They are either tagged, carried off and eaten (by macrophages, a hungry type of white blood cell that engulfs enemy particles) or excreted.

It is of course the tagging efficiency of our immune system which makes HIV so deadly, cos it is CD4 cells that do the tagging. Sticking out of each primed HIV viron-bomb is a piece of biochemical nougat (a glycoprotein) which CD4 cells, among others, deem exciting foreign trade, and get all excited about latching onto...which is their downfall.

The broken up amino acid sequences are quite specific to HIV. Viral load tests look for these signature amino acid strings.

This is an essential piece of detective work if you want an easy-to-do, stable, routine test, since HIV cannot exist very well as a whole entity in the body. Therefore in a blood sample the surest thing to measure is broken up bits of HIV.

Measuring broken up bits of genetic or biological material is the basis of all PCR-based tests, which is a standard biochemical "fingerprinting" technology at the moment including for many viral load tests. Indeed this test method deliberately breaks up biological material to measure it.

I'm ready for my close up now, Mr de Mille

- matt

[sam66]

 mmh,     undrestand, me thinks,

 ta