Necessity of sensitive PCR/TMA post tx?

[dointime]

I can understand having a very sensitive PCR/TMA before stopping tx, ie. a confirmed positive would predict relapse and offer the choice to continue with tx.  What I'm wondering about is whether a post tx test needs to be all that sensitive?  Whenever I've heard about a relapse, the VL numbers have increased sharply within the first 12 weeks into the thousands at least.  

So my question is, has anybody ever heard of a (post tx) relapse where the VL numbers remained extremely low for the whole 6 months such that a very sensitive test would be needed to detect it?  Is the possibility of this the reason why you would still go for the sensitive test, despite the extra cost / hassle?  

Thanks    

        

[mremeet]

Just so you know my post tx PCR schedule is a bit different than everyone else's. My study nurse scheduled me at 2 weeks post and then inadvertantly scheduled me for 6 weeks post, when it should of been 4 weeks post. I didn't care though, in fact I liked a 6 week interval better considering how far I have to drive to the study center (2+ hours one way). I know you're in a similar situation too, maybe something to think about. Anyway, just so you know that my test schedule isn't the same one you'll find in the trial protocol.

It's great to hear the rash has made its rounds and left the building, for now anyway. Hopefully it won't be back, or at least if it is it won't be as bothersome as before. And yeah the joint pain is kinda creepy and worrisome, sorry to hear about your back pain. My god I hope the arthritis/joint pain thing does NOT stick around. And I can only imagine a sore back, that's the all time worst. But with any luck these things will sort themselves out in time, that's what I'm praying for anyway (perhaps foolishly). Funny how these symptoms ebb and flow and come and go. It's similar to what Forrest Gump said "SOC treatment is like a box of chocolates, you never know what you're gonna get." Or more like the counterpoint someone told me once "Life ain't like a box of chocolates, life is like a box of jalapenos - what you do today can burn your a$$ tomorrow." ;-)

[dointime]

Hi mre,
Thanks for letting me know your post tx PCR schedule.  Hungry was drawing up his (he's counting the days) so I thought I might as well get mine planned out while it was fresh in my mind, though my post tx is still an eternity away.

I got over that friggin rash but it took the whole month of July to work it's way round my body.  I don't suppose I've seen the last of it but I'm thankful it was controllable using the Elocon steroid cream.  I was half crippled by lower back pain at the same time but that has gone too now.  I see on another post that you have been having joint pain.  It's no joke, the loss of mobility.  What next?        

[mremeet]

I don't think a super sensitive PCR is necessary post tx except in cases where the patient plans on restarting treatment in the event an early (low level) relapse is detected. Also, I've heard of rare cases where someone could maintain a persistent very low level active infection which might not be picked up with a relatively insensitive test. Otherwise, I think a reasonably sensitive PCR (like <30 IU/ml or less) would be fine. As you know the main thing is to be tested after stopping tx over and over again for a period of 0-12 months to ensure it's gone for good (assuming no relapse of course). Speaking for myself, since I have no intention of restarting treatment in the event of a relapse, I'm real comfortable with our 10 IU/ml test at 2/6/12 and 24 week post tx intervals. I plan on following up with a 2 IU/ml PCR some time after that (probably a little after 1 year post) to cap it all off, just to have a sense of confidence that it really and truly has been put out of business for good.

Hope you're hanging in there ok and the skin issues haven't gotten any worse and are reasonably tolerable (I say "reasonably" because there's no way they could ever be considered just plain tolerable ;-)  Also, have you heard from hungry? Hope he's making his way to the end without too much trouble.

[jmjm530]

A <15 test should be fine both for EOT and post treatment.  When I said 'why not get the most sensitive test available', I was referring to tests here in the U.S. Should have said get the most sensitive test *readily* available. Don't think shipping your blood to Nichols for another 10 IU/ml is worth it. In fact, anything 50 IU/ml or under should be fine, if that's what is available in your area.

-- Jim

[dointime]

Hi Jim, yes that makes sense to me, thanks for your input.

I asked because I live in the UK, it's not the norm here to get private PCR's, and neither the medical profession nor the labs cater much for it.  The major teaching hospitals have the Bayer Versant technology but there's no individual access as far as I can make out.  Quest have a London base where they will do a PCR RNA <15 IU/ml and it is relatively easy for me to post them a sample.  I haven't asked them yet what's involved in them shipping to the Nichols in CA, or if I have to go to London to give the sample & get it centrifuged and frozen within 2 hrs - but you can see what I mean about the cost and hassle.  

So I'll still get the TMA done one time prior to finishing tx, supposing Quest will in fact ship it for me, but I had to question why it would be worth it (in my situation) for my post tx PCR's.    

            

[jmjm530]

Don't know the schedule of your viral load tests but your doctor apparently is making the assumption that you are still undectectable. But without an EOT test, as you say, it will always be unclear whether your relapsed or had a viral breakthrough, should you not SVR. I would ask for an EOT test and have the blood drawn six days after your last peg shot which should be the last day you're taking ribavirin. After that, a 12 week post treatment test is an excellent predictor of SVR, but testing 4-6 weeks after your last riba pill also will correlate close to 90% with SVR. Best to get the most sensitive test avaialble, something like Heptimax from Quest Diagnostics that goes down to 5 IU/ml. Really can't comment on the 72 weeks as I don't know your stats, but in general 72 weeks is reserved for slower responders -- a geno 1 who was still detectible at week 12 but UND at week 24. If you fall into that category, then you might want to discuss extending tx with your doc.

All the best,

-- Jim

[ejoli]

I was wondering about that. I took my last(48th) shot last night(yes!) and was wondering when I should do my eot pcr. My Dr. didn't really say, but wants to see me on the 22nd with reg. blood test results. He said I didn't need a pcr untill 3 months. I knew this wasn't right because how would you know if you relapsed or had a breakthough of the virus before the end of treatment. Oh, I hope that it worked!!! but with my 3/4 biopsy I wonder if I shouldn't do 72 weeks. I know that my bloodwork couldn't handle it though.   Thanks for the info though,    -Libby

[jmjm530]

There was a study that showed that less sensitive end of treatment (EOT) PCRs often gave false negatives when the person was really positive by a TMA (more sensitive) test. 100% of the PCR positive/TMA negative group relapsed. The EOT test is taken six days after your last Peg shot which would be the day of your last ribavirin pill.

Beyond that, in all probability, by six months time you would either be non-detectible or have a reasonably high viral load and therefore a very sensitive test wouldn't be necessary. That said, "in all probability" does not mean ALL probabilities, and everything I've read suggests getting the most sensitive test possible post treatment and to confirm your SVR. The question to me is not why should you get the most sensitive test available, but WHY NOT get the most sensitive test available. There should be no extra "hassle" and the cost isn't all that much more than a real-time PCR, plus insurance should cover it.

-- Jim

[jmjm530]

First sentence should have read in part:

100% of the PCR negative/TMA positive group relapsed.