I understand your concerns as I have had the same thoughts but I think DoubleDose's explaination is excellent.
Here in NZ we use the Roche COBAS Ampliprep/Taqman HCV test sensitivity 15IU/mL with a linear range of 43 HCV RNA IU/mL to 6.9E+7 HCV RNA IU/mL (which would seem very close if not the same test as yours). I questioned my study team as to why the more sensitive tests were not used and their response was that particular test has been proven to be more accurate than the more sensitive tests. It is also the test the FDA accepts as being the "standard" to determine UND and SVR status.
I have also read reports on the net comparing the different tests reliability and it would seem this data is backed up by several studies, however, I am unable to provide you with the links as I investigated this a few months ago and didn't bookmark the pages. It appears that the more sensitive tests are more prone to false negatives and false positives so, as DoubleDose has explained, the fact that you are CONSISTENTLY coming in with the same result as UND to senstivity of what is considered the most reliable test is a good indicator that the virus in undetectable in your blood.
I hear your point about the lower detection limits, but the is a world of difference between less than 612 and less than 15 or 10. There have been other posts explaining this in excellent detail however, as usual, they were read when I was amidst the fog and I have forgotten details and have no links.
By all means, request the Qualitative rather than Quantative test EOT because it sounds like it will ease your mind but my gut is telling me the same as DD, as that you are truly UND at this point. Also being a Geno 2 is a great bonus!!
All the best!
Epi :)
looks like you had the Labcorp Quantasure Plus test. this tests range is from 43 to 100 million. This test replaced the <10 test with the same name "Quant Plus". This test is fine during treatment but at end of treatment I would ask for the more sensitive test, Labcorps "Quantsure" NOT "plus". Then if unde at that test you could switch to the less expensive Qualatitive tests that simply state pos or neg.
good luck
It’s frustrating; I’ve found if we use the ‘less than’ and ‘greater than’ symbols *in that order* in a post, they mess with the HTML code, and delete everything in between those two symbols. I think the best way around this is to actually spell them out as I did above; I’ve been baffled about this in the past,
Bill
I think the missing left arrow is being filtered out because that character is also part of an html tag. I think html is suppressed on this board.
I give up. The comment above is missing most of what I wrote. I am not sure why the site is editing out the symbols that I put in the text. You get the idea though. is greater than.
Not sure why above sentence did not post as I wrote it. What I had said was that this symbol means less than: < , and that when you indicate less than 43 copies it should read: " 43" (which would mean greater than 43) as was indicated in your initial thread. Somehow the symbols that I included in my opening comment, disappeared on posting!
DoubleDose
Do you have a copy of the lab report in hand, or did you receive this result by telephone?
I ask because some (many) of the PCR tests with a lower detection limits of 50 (which, as you say, is reported as <43 -- the test I used at Stanford is this way.) These tests have a qualitative and quantitative component.
I stopped treatment early because my tests were coming back <43 but DETECTED. This means that I had a low level of viremia (some where between 1 and 49).
Ask for a copy of the lab report paper to double check.
I agree with the thinking that this test IS important at this stage of treatment, but not critical.
Just a comment on your viral load description above: Less than 43 is designated by the following symbol: 43 as you indicated. Just to clarify, and avoid confusion.
Also, if your post-tx PCR's continue to show <43, on a quantitative basis, it will be just as valid as using a Qualitative PCR that gives you a 'yes' or 'no' response. The reason is that if you still had the virus, it would very quickly reproduce to well beyond 43 copies/ml., and hence the quantitative test would show some numerical result, positive for the virus, and at least in the thousands, ten thousands, or more likely hundred thousands or millions. The virus would not just linger around at minus 43 copies, for long periods after tx. If it reads <43 copies, then it is for all purposes...gone. SVR.
DoubleDose
That's a good response in one week but I think if it went from 1.8 million to eight hundred thousand it was actually less tha a log reduction..
No. I was tested 1 week after tx started( 2 log drop), 1880000 drop to 800000.
But, no test goes to zero. Therefore, it's possible with any test that there may be virons that can't be deteded even though they may be there. That's why knowing the sensitivity of any viral load test is important; to know the possibilities of what you don't know. As a geno 2 and indetected the liklihood of a breakthrough is small, but not impossible and if you were to breakthrough it's likely that it would be above the limits of detection of a typical pcr. Was week 12 the first pcr after starting treatment?
An undetectable level means that the viral load test isn't able to detect any virus. However, you can have an undetectable viral load but still test positive for viral hepatitis. This is because viral load tests have a limit to how few viruses they can detect. Any amount of viruses fewer than that limit will be undetectable. Tests vary in terms of sensitivity. For instance, while some viral load tests can detect as little as 50 IU of virus per mL, others can only go as low as 615 IU/mL. This is why I am concerned.
No test goes produces results to zero; none of us know that the virus is completely gone, regardless of how sensitive the test is.
While the qualitative test might yield slightly more sensitive results than the qualitative, that isn’t much of an issue at this juncture. How would a more sensitive test change the course of your treatment? This is the question doctors ask themselves.
Over nearly five years and literally thousands of patients in this forum, only three of four genotype 2 patients have relapsed; my hunch is you’ll respond predictably, and go on to achieve SVR. You’ll be fine :o).
Bill
At this point in treatment (undetected) it really dosen't matter if it quant or qual if the result continues to be undetected. If you know the name of the qualatative test ordered it's easy to find its sensitivity. Do you know the specific name of the test?
I completely understand your point, I am not trying to get the lab to anything it is the doc I am worried about.
You'll have to go to your dr & have him rewrite the lab requests... The lab will not be change the tests on your word alone.