What if I have a positive IgM and Bart from Igenex, but both were negative with MDL?? My PCR from Igenex was negative as was my IgG. What should I determine from that?
Is MDL a reputable lab? Is Igenex better? How does one go about reconciling different results from two labs that are both reputable regarding testing for tick borne illness?
Which do I believe????
Posted by seibertneurolyme (Member # 6416) on :
In my opinion, you can believe a positive test result even from bad labs like Quest and Labcorp probably 99% of the time.
I recently had a phone conversation with the lab director at MDL -- he said PCR Lyme tests from a skin biopsy of a Lyme rash were usually positive 75% of the time. That is just one example where a test is a lot more likely to give a false negative than a false positive.
Several LLMD's have told hubby that they always believe a positive test especially combined with clinical symptoms. They say that a negative test doesn't mean anything to them -- they just ignore it and make a diagnosis based on clinical presentation. False negative tests are the reason that Lyme and tickborne coinfections are clinical diagnoses.
Bea Seibert
In my opinion you have both Lyme and Bart.
Posted by Aniek (Member # 5374) on :
Igenix is known for returning more positives than MDL.
That either means that Igenix has more false positives or that MDL has more false negatives. Nobody knows for sure.
Igenix gets a lot of support for the Lyme community as the most reliable. I have heard from an LLMD that there are more cross reactions through Igenix giving false positives than through MDL.
I don't really have an opinion because I don't know the science. Except I know a negative PCR always means diddlysquat. That's the nature of the PCR test.
Always remember, clinical diagnosis.
Posted by bpeck (Member # 3235) on :
MDL is an acredited Lab, and in alot of people's opinoins (including mine) they are excellent. They are a dignostic lab- therefore don't test of Osp A and B just like every other US diagnostic lab.
Igenex is a reference lab (and the best place IMO for a western Blot becuase they do test for OspA and B)
The problem is that nothing is standardized with any of these labs - so some labs sensitivities and specificities vary quite a bit.
The Lyme test at MAYO is the worst IMO
Posted by vachick (Member # 8353) on :
I was just curious because my doctor said I didn't have Lyme when the MDL test came back and then he said I do have Lyme when the Igenex test came back!! I did a urine PCR test...not that that matters I guess.
So, I was confused as to what to believe! Then my CD57 came back at low 20's and I think that along with my symptoms made it more definitive for him.
However, I am in the midst of starting medical treatment at Bethesda Naval Hospital and I have to explain all of my lab results to a new doctor. You can see how confusing that may be?!?!?
Posted by ChrisBtheLymie (Member # 8916) on :
quote:Originally posted by vachick: I was just curious because my doctor said I didn't have Lyme when the MDL test came back and then he said I do have Lyme when the Igenex test came back!! I did a urine PCR test...not that that matters I guess.
So, I was confused as to what to believe! Then my CD57 came back at low 20's and I think that along with my symptoms made it more definitive for him.
However, I am in the midst of starting medical treatment at Bethesda Naval Hospital and I have to explain all of my lab results to a new doctor. You can see how confusing that may be?!?!?
IMO, you can be pretty damn confident you have Lyme.
Posted by SForsgren (Member # 7686) on :
You could take a CD57 of 20 and say that you have Lyme without any other supporting evidence. To my knowledge, there is nothing known to lower CD57 today other than Lyme Disease. A 20 is a pretty clear indicator. I'd stop looking and start the healing journey....
Posted by Mo (Member # 2863) on :
It depends on the test. Each of the labs has their specialty and expertise in different forms of TBD testing.
In addition to BPeck's comments - I want to add that a positive PCR from MDL (they are particularly skilled and experienced in this test) .. is scientifically indisputable. MDL is known to have the most sensitive PCR test.
HOWEVER.. a negative PCR only can confirm that the DNA was not in the tiny specimen used for the test. A negative PCR in no way means one does not have an infection. (I would think any Doc should understand that when you talk about it)
Igenex is notorious for the highest level of sensitivity in the Western Blot -
-- however, no single test can give you difinitive answers.. based on the accuracy levels and the very nature of the diseases, and immune response variables, ect, ect..
Mo
[ 04. August 2006, 10:09 PM: Message edited by: Mo ]
Posted by Lymetoo (Member # 743) on :