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I tested Negative

CBS

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Changes of a false negative

I don't want to confuse anyone any further but I do think that it is important to reiterate one of Kurt's earlier points. All of the numbers being tossed around (% found positive with this or that test) are based upon 101 'CFS' people (however that was defined) in a single study.

The chances of a false negative are entirely dependent upon the incidence in the population and the population of CFS patients is as poorly defined as W. Reeves could have ever hoped.

This is an exaggeration of nearly any realistic scenario (but sometimes exaggerating the elements of an issue is useful in identifying pitfalls); say you have a lousy test that only correctly identifies one of every two patients with a particular disease but that disease only occurs in one of every 1000 people. You're going to get one positive test in 2000 tests. HALF of the positives will be missed but there will only one out of 2000 that got a false negative. Again, these numbers are extreme but they raise some of the central questions about testing accuracy. And this is only one half of the equation. There is the whole issue of false positives.

So, when you ask if there is a one in three chance that a negative result is a false negative, that cannot be answered right now because there are way too few patients in the WPI study and I can't name a single variable that I don't expect to change at least to some degree over the next several months as more studies are completed (In Dr. Bateman's excellent speech she predicts that in some cohorts, the number of positive XMRV tests will be no higher than the positives in the controls).

And on top of all this, we don't know what, if any, the true relationship is between XMRV and CFS.

From where I sit, there is a huge amount to be excited about and there is a lot of reason for hope (and quite frankly, nearly all of the subjective, 'backstage' signs look good - people on the inside who are talking keeping staying excited, movement at the NIH, Ivy League Colleges opening positions dedicated to CFS and XMRV etc.).

But as anxious as I am to "find out" for myself, I would not have a clue as to what to do with a negative (or positive) XMRV test at this point in time.
 
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Thank you Kurt - wow.

It's not exactly black and white stuff is it!...At least not to someone with my modest understanding.

Trying to understand it at your level is putting pressure on the grey matter today ;) Think I'd better stick to putting Christmas decorations up. After a cup of coffee I'll go back and read more of your posts on this.

But...

For a test, I'll play it safe and wait.

Actually, um, I have no choice but to wait because Reno is a half a world away, and I'm not well enough to travel right now. :) Much appreciate your input!
 
I

imready

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Jim

Hey Jim you asked me to describe my symptoms, here ya go. I've had CFS for over 19 years and it started with the Epstein Barr virus. I have all the virals, EBV, CMV, HHV6 their are two more viruses that I have but I can't think of them right now. I don't have fibromyalgia, but I do have pain in my hands and ribs at times. I can't exercise and I feel best when lying down. My CFS is Moderate to severe. I'm unable to work, but i'm very lucky to have the best husband on earth!!!
 

Jim

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immune system status?

forgot to ask - do u have any immune system test abnormalities? like nk cell function or rnase l? low nk function seemed important to dr peterson, tho i know rnase l abnormalities did not prove to be a factor in this study.

glad u have the best husband. i have the best fiance. ;)
 
I

imready

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Jim

Yes my NK cells were so low that my doctor at the time sat me down with a serious face and said "Don't panic over your low NK cell count" and at the time I didn't even know what NK cells were. I just pulled my records out and my NK cell funtion was 4, the reference range is 8-170.

I don't think I was tested for the Rnase-L test, does that test have to do with my sed rate?

P.S. I suggest you marry the girl quick. :)
 

Jim

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no, rnase l is not related to sed rate. it's part of an antiviral pathway that is often abnormal in cfs. and apparently in prostate cancer, tho perhaps not in the same way.

anyway, with such limited info on what we know so far with the xmrv testing, it's hard to say if u would be a standard candidate for xmrv positive. low nk function, sudden onset, and many co-infections could suggest xmrv. but maybe one of those infections is what causes your cfs. or some immune/genetic problem, possibly the low nk function itself.

still, for some reason i would have guessed u would be positive. and maybe u will indeed prove to be positive when the testing becomes standardized and well-established. i would think VIP knows what it's doing tho, as they are apparently doing the xmrv tests the way dr silverman does them, the researcher who discovered xmrv. one would think he knows what he's doing. but maybe u are one who will prove positive through antibodies. all we seem to do is guess and wait impatiently for more solid info to come out. it's a bit maddening. ;)

jim

ps yep, plan to marry her as soon as we are healthy. i'm first in line on her list of candidates, so i'm hopeful. ;)
 

fresh_eyes

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@ ladybug - Pretty sure it's imready who got their test results back, not Jim. I know, it's totally nerve-racking watching the results come in...Deep breaths...(that's aimed at me, not you - but you can do it too if you want. :))
 

fresh_eyes

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Hi Ladybug. If you need something to keep you hopeful about treatments, I suggest you watch Nancy Klimas' presentation - she's very positive and so competent and reassuring. I think she addresses this very question (her or Bateman? Recently posted) in a Q & A with the audience, and says, while she thinks younger people will probably recover quicker due to just better immune system, length of illness probably won't have much to do with it, judging by her experience with HIV. So, good news on that front.

i was all happy thinking that once we get on the right drugs, everything would be ok ...but that isn't true.
Be strong! Hang tough! Vive la revolucion! There's much reason for hope! :)
 

gracenote

All shall be well . . .
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however that was defined

I don't want to confuse anyone any further . . .
I think you just confused me further ComeBackShane. Or perhaps I did that all on my own. :)
All of the numbers being tossed around (% found positive with this or that test) are based upon 101 'CFS' people (however that was defined) in a single study.
If you're referring to the chronic fatigue syndrome patients used in the study, they used the Fukuda and Canadian definitions to identiy them, so they are not from Reeve's overly broad definition.

The chances of a false negative are entirely dependent upon the incidence in the population and the population of CFS patients is as poorly defined as W. Reeves could have ever hoped.
If you're speaking of those in the general population who have been diagnosed with CFS who are now being tested, then you may have a point. We would want to know by what criteria they have been diagnosed before we could draw any conclusions as to the meaning of the results.

----------
ETA: I think I missed at least a whole page of posts when I responded to this one from ComeBackShane. I think I DID confuse myself all on my own!!! At least you can link back to the post I'm referring to from way back ages ago, if you are still interested!
 

fresh_eyes

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I mean, like an analogy, if I'm testing whether there are any fish in the ocean using a bucket to scoop up some water, my eyesight is very sensitive (100%) to whether there is a fish in the bucket. But if I didn't scoop a fish into the bucket in the first place, that doesn't mean there's no fish in the ocean.
Nice analogy, CF. Also your test would have 100% specificity - false positives *extremely* unlikely.
 

Kati

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So sorry you tested negative. It doesn't mean you are negative- just means they haven't found signs of active disease.

After watching Dr Klimas and Dr Bateman's lecture and the greatest of the great retrvirologist (Dr Coffin) it sounds like it would be best for your soul to wait a little bit to be tested until they figure out a better test.

Obviously the people that have had these tests done are "legit" no doubt about that.

Dr Bateman also warned that some replication study results will come back negative, and to expect that. Reasons about that? Different lab technique, different cohorts and choice of defintion (Reeve's disease) amongst others.

On a more positive note, the doctors are all excited about the retrovirus. Dr Klimas, Dr Peterson, Dr Coffin, Dr Bateman, and Dr Bell came out of retirement to reopen a study of his from 25 years ago. It's all good. ;)
 

Dr. Yes

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I've been going back and forth on this one. I had been highly skeptical of the XMRV findings from the get-go, but the excitement of the scientific community and the quality of the WPI study have softened that skepticism a lot... It's hard to be objective when you are so desperate not just for a cure (which is hard to imagine after being sick so long) but for validation, recognition, and ethical treatment by everyone from doctors to government programs to family. Maybe the greatest unseen stressor and contributor to this disease is the constant, often subconscious knowledge that people don't think your sick, or have their doubts, and that nobody (including you) seems to know what you are sick with. And even you start to have nagging doubts... that is the worst thing to make a sick person feel - that they are to some degree doing this to themselves.

Under normal circumstances, I would definitely wait until they develop a reliable, sensitive test. I used to do some research (as a technician) in immunology and molecular biology, and I know how long it can take to refine a test for maximum efficacy.

BUT, in my case, I happen to be at a very risky crossroads and cannot afford NOT to get the health benefits I need from Medicaid, doctors, etc etc.. I don't know that a positive XMRV test would mean anything to them, but every little bit I can do to tip the scales... For that reason, I'm thinking of volunteering for research at WPI (if I can get a free test out of it!). If it's negative, I can always get re-tested when they finally get a reliable test out there... I don't want to have XMRV, by the way; not a fan of nasty retroviruses...but I think we all are attracted to it because we can't stand having "Unknown", or "Nothing", as other perceive, it, anymore.

ladybugmandy - I definitely respect how you feel; believe me I've considered the same thing. But - and this is just my personal opinion - I'm concerned about the idea of taking AZT this early in the game and even with a negative XMRV result. AZT is a pretty toxic substance, much more so than any of the antivirals PWCs are used to taking. Being as sick as I am, I don't think I could take heavy side effects right now, and would have to be stronger first; the risks are too great at this point, when we know so little. Just my take, though.

i have the best fiance
I'm all alone. :( (cue violin music)

ps yep, plan to marry her as soon as we are healthy. i'm first in line on her list of candidates, so i'm hopeful.
Jim, your fiance has a "list of candidates"?!?!?:eek:

If you don't marry her soon, I may try to get my name on that list!.:D

p.s. - Hi Freshie! I thought you were going to take a much-deserved rest??
 

CJB

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<s>
BUT, in my case, I happen to be at a very risky crossroads and cannot afford NOT to get the health benefits I need from Medicaid, doctors, etc etc.. I don't know that a positive XMRV test would mean anything to them, but every little bit I can do to tip the scales... For that reason, I'm thinking of volunteering for research at WPI (if I can get a free test out of it!). If it's negative, I can always get re-tested when they finally get a reliable test out there... I don't want to have XMRV, by the way; not a fan of nasty retroviruses...but I think we all are attracted to it because we can't stand having "Unknown", or "Nothing", as other perceive, it, anymore<s>?
Dr. Bateman did say in her presentation that was one of the legitimate reasons to get tested. She acknowledged that it might not be accepted as proof of illness, but a positive test result might help winning benefits.

I hope you win your fight. I know how terribly difficult it can be.
 

Kati

Patient in training
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I've been going back and forth on this one. I had been highly skeptical of the XMRV findings from the get-go, but the excitement of the scientific community and the quality of the WPI study have softened that skepticism a lot... It's hard to be objective when you are so desperate not just for a cure (which is hard to imagine after being sick so long) but for validation, recognition, and ethical treatment by everyone from doctors to government programs to family. Maybe the greatest unseen stressor and contributor to this disease is the constant, often subconscious knowledge that people don't think your sick, or have their doubts, and that nobody (including you) seems to know what you are sick with. And even you start to have nagging doubts... that is the worst thing to make a sick person feel - that they are to some degree doing this to themselves.

Under normal circumstances, I would definitely wait until they develop a reliable, sensitive test. I used to do some research (as a technician) in immunology and molecular biology, and I know how long it can take to refine a test for maximum efficacy.

BUT, in my case, I happen to be at a very risky crossroads and cannot afford NOT to get the health benefits I need from Medicaid, doctors, etc etc.. I don't know that a positive XMRV test would mean anything to them, but every little bit I can do to tip the scales... For that reason, I'm thinking of volunteering for research at WPI (if I can get a free test out of it!). If it's negative, I can always get re-tested when they finally get a reliable test out there... I don't want to have XMRV, by the way; not a fan of nasty retroviruses...but I think we all are attracted to it because we can't stand having "Unknown", or "Nothing", as other perceive, it, anymore.





QUOTE]

CJ, I understand your point, it is valid, and I have been tempted to do that test for the same reason. My disability has been approved for the wrong reasons, but still my financial status is not much better, I don't know for how long (they want me to do physio for 6 weeks and then return to work- like if by magic, I can do that)

I still have other avenues left (my first rheumy appointment in the new year, some immunologic testing, low cortisol being investigated) and will do that and worse come to worse, I will do physio and prove to them that I am not able to return to work- my functional assessment resulted in severe joint pain and even less capacity to take care of myself.

I wish you luck, and in your case, I hope you get tested positive, especially if it's the only way to get benefits. I am sorry the system is so crappy that we have to resort to that.
 
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test results

Hi impatient, It is still so early in terms of what will be discovered. If Nancy K. suggests waiting to test....I can try that, Remember RNase testing ?...my result was low having been ill for several years when tested. Dr. Cheney had explained that I had a lower number probably due to length of time of my illness. Can understand how you are feeling. I worked in medical area for many years and am in awe of those who spend their time working for us. It feels like more doors are opening and better days may come before long.
SueC.
 

fresh_eyes

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thanks fresh, etc. i just dont see how you guys can be so positive and optimistic. i wish i could.

maybe i don't have enough emotional support, maybe my life was very difficult even without this illness, maybe it is just my nature to worry...

drs bateman and klimas HAVE to seem optimistic..thats their job. one pessimistic word from them could trigger a bunch of suicides and they are very aware of that.

i thought i had let go of finding some happiness...of falling in love...of not being sick and alone forver....but the XMRV news must have given me a little hope because now i am a wreck again everytime i hear any bad news!

sue
xoxo
Shhhh, shhhh, shhhhh....(strokes ladybug's head :))

ps Some of us are not so very ill, so it's a bit easier.
 
I

imready

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Testing

I'd like to address the comments from others about testing.

Here are a few comments I've read, wait for a reliable or more sensitive test, testing will be improved with less chance of a false negative, retest when they have the antibody test, testing has issues right now, Invariably they find ways to improve it.

I agree with all of these statements, It's one of the reason's I'm not so distraught over my test results. Now I'll just wait to see if XMRV is the puppet master, then retest.

What is a little irritating for me is that on WPI web site and VIPDX they don't put anywhere on their websites a disclaimer (not sure if that is the right word) stating that this test is new and all the kinks haven't been worked out and not 100%. Maybe they think they have mastered this test and all test results are correct.

Here is part of WPI's press release regarding VIPDX testing.

In response to an overwhelming request for a diagnostic test for XMRV, WPI has temporarily agreed to allow Viral Immune Pathology Diagnostics (VIP Dx) to begin offering the identical tests that have been extensively validated using the same technology developed by Drs. Lombardi and Mikovits
and their colleagues as reported in Science.

After I received my Negative test results, I emailed VIPDX this question.

Real fast question...

I just talked to my doctor and they received my test results back from VIPDX and they were Negative. I order this test XAND - XMRV screen by PCR with virus culture confirmation: Test Code XAND ($650) .

So if the results are Negative then I'm definitely Negative for this virus correct? Or is there going to be another test coming out? I guess my question is for $650 I'm sure that your testing technicians looked at every angle of my blood for this virus and it is Negative. So I can be assured by this test that I don't have this virus?

Here is the response back from VIPDX.

We run this test several different ways and Dr. Lombardi screens the results before he sends them out. What this means is that there is no virus detected. Some time in the next year, there will be an antibody test screen for this virus (still in development). Please check with us in February.

It would seem that WPI and VIPDX feels very confident of their testing procedures. So at this time all I can do is sit and wait, which I have mastered over the last 19 or so years :)
 

Jim

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valtrex

ladybug,

i was told by dr mikovitz that it is ok to be on valtrex for the xmrv test. i was on it and came back positive. apparently we can assume that valtrex does nothing to help get rid of xmrv.

jim

ps Dr. No Way, sorry, my fiance's list is full with 1 name. ;)