Viral Load Tests

Are Qualitative Blood tests obsolete?  It not, how does one go about getting one?  Doons

[friole]

As I understand it (and if I am wrong, someone please chime in)a qualitative test tells you if your blood contains the virus.  A quantitative test gives you the count per mL.  I don't think the qualitative is obsolete, but once you know you do have the virus and are treating , you will want a sensitive quantitative test.  I know there are others here that can explain that much better..

[GoofyDad]

Forgot to post this:

A M Qadri and others. Predictors Of Treatment Failure in Patients With Hepatitis C Genotypes 2 or 3 Infections. Abstract S1565. DDW 2005. May 14-18, 2005. Chicago, IL.

[GoofyDad]

I somehow destroyed a bookmark and consequently lost a link to a paper from DDW 2005 describing higher relapse rates for geno 3 patients with history of alcohol consumption. Wanted it for an appt tomorrow. Can anyone help with a link?

I did find a very abreviated abstract, but that's not very helpful to me.

Thanks for any help!

[GoofyDad]

Qualitative is better at detecting virus at very low levels. It's a boolean test: Yes or No. TMA is currently the most sensitive Qual test.  

Quantitative is more useful for measuring viral load levels, rather than a yes/no proposition.

I've heard that if you relapse, the virus will replicate pretty rapidly, so post tx, once virus is detectible on the Qual test, it should soon also be detectible on the Quant. Generally, I think the TMA has more value during tx than it would post tx.

On the other hand, I think I read a study that suggested a 3 mos post tx TMA is as predictive as a 6 mos less sensitive test.

Those opinion, of course, conflict with each other.  

OK - <a href="http://www.questdiagnostics.com/hcp/topics/heptimax/heptimax.html">Here's a link that should help</a>.

[GoofyDad]

Thanks for the links. I'm through over analysing this. Stop date is 3/11 - 26 weeks. May wind down with 2 addt'l wks of partial dose - we'll see on that.

[jmjm530]

The short answer is "no" although many of us are replacing qualitative testing with quantitative testing of similar sensitivity such as Quest Diagnostic's Hemptimax TM. (See Goofy's link above).

The advantage of Heptimax, according to Quest, is that you only have to order one test throughout treatment rather than start with a quantitative and then later switch to the more sensitive qualitative.

Heptimax is done in two-parts. First, a standard quant is run with a sensitivity down to 50 IU/ml. Then, and only if the first part is negative, TMA technology is used with a sensitivity down to 5 IU/ml.

But unlike a standard qualitative -- if positive, with Heptimax you will still get a number (for example TMA=15) as opposed to simply just a positive.

A lot of folks here use Heptimax including myself. Quest also has a very good qualitative with a similar sensitivity. LabCorp is another well-respected lab with sensitive tests.

-- Jim

[strator]

hey fella, not sure if this helps. http://www.hivandhepatitis.com/2005icr/ddw2005/main.html#hcv
Don

[can-do-man]

Not sure if this is it.

http://www.hepcnet.net/boards/medsforum/index.cgi?noframes;read=3914

[cuteus]

goof, you two? I had two extra wk of partial dose of IFN, no riba! no idea why i did it.