Qualitative detection limit for Labcorp test 550400

Hello,

Does anybody here know what the lower detection limit is for labcorp qualitative test #550400 is?
Thanks!
Pete

[cuteus]

I would call labcorp and ask them, they are pretty good in customer service. Or ask the lab technician. this post http://www.medhelp.org/posts/Hepatitis-C/1-year-post-test/show/1161397  might assist a bit.  If you get  a negative, that is all you need to know> GL!

[upshotphx]

OK thanks. I emailed them and asked. I was hoping maybe someone on here has had that test done before and knew the detection limits.

[upshotphx]

Well I heard back from the technical consultant and this is their reply. Maybe this will be helpful to others for future reference

"Lower detection limit for the HCV PCR qual is 50 copies"

[flcyclist]

Your information agrees with the following:

Qualitative HCV RNA tests include the qualitative RT-PCR, of which the Amplicor™ HCV 2.0 (Roche, USA) is an FDA- and CE-approved RT-PCR system for qualitative HCV RNA testing that allows detection of HCV RNA concentrations down to 50 IU/ml of all HCV genotypes (Nolte 2001).

http://www.flyingpublisher.com/0011_03.php

[upshotphx]

Thanks flycyclist. Interesting that they would offer that test when their regular RT-PCR Quantitative test has an ability to detect HCV genotype 1 down to 7.1 IU/mL and for genotype 2 it is 15.3 IU/mL.

Reason I'm curious is because it appears that I have cleared the virus sponateously. I was diagnosed 4.5 years ago and had multiple antibody tests, and a viral load test as recently as 2.5 yrs ago to confirm it. went to doc to get genotype testing and the test couldn't be done because it has a cut-off of 600 IU/mL. Then got the taqman RT-PCR quantitative and it said "not detected".  Went back in and am waiting results on the above referenced qualitative.  If this comes back negative I'm going to ask doc to do the NGI quantasure with a sensitivity down to 2 IU/mL. At that point I guess I am free and clear right?  Doctor has never seen this before so he doesn't know what to do.

[flcyclist]

It could be the difference in cost between the qualitative and quantitative tests.
I understand your desire to use the most sensitive PCR available just to make sure.  Labcorp's RT-PCR Quantitative limit of detection is 7.1 IU/mL for HCV genotype 1, and the quantifiable range of the assay is 25 IU/mL.  I believe Quest's limit of detection is the same, but their quantifiable range is 43 IU/ml.  

Is it worth the cost and additional waiting period for the NGI quatasure test?  If you did have HCV, I'd suspect the viral load to be higher than 7.1 IU/mL.  But again, I understand your approach.  

[upshotphx]

Well for me the cost isn't a consideration. I get free labs through them as an employee. I just want to be as absolutely sure as possible. I have read the study about patients with very low viremia, so yes I am a little(a lot) paranoid, and just want to be absolutely sure and close the chapter on this once and for all.  Frankly I'm still in a state of shock over the fact that from all appearances I don't have it anymore.

[upshotphx]

Just an update. It seems like the lab performed the wrong test. From what I could tell over phone, an antibody follow-up test was ordered. Of course I tested positive, but the s/co was 6.5. Now I've gone back and had the NGI quantasure test done. Am waiting results on that. Will post when I get labs back.

[upshotphx]

Just an update. Got my ngi quantasure test back and i'm undetectable. Looks like I spontaneously cleared the HCV. Thank God what a miracle. I'm in a state of shock.

[tired2013]

Good info and congrats!