posted
Its the first Elisa that I have had it was negative. The Western Blot is not back. The Western Blot I had in Januar was positive for IGM 41, 23, 39.
If I have Lyme, its late lyme. Is is possible to have negative Elisa and positive Western Blot. I just want to b diagnosed with something and get it over with.lol
Posts: 347 | From WV | Registered: Jan 2007
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posted
Gingivitis. ummm. I think I will do my research on that...
Does it cause joint pain, fatigue, memory loss, stroke, headaches, bowel incontinence, etc.
If so, I will take that diagnosis to my dentist, actually he is the only one I have not seen for my problems, I cant believe I even left one medical professional out.
Worth a shot. huh
Posts: 347 | From WV | Registered: Jan 2007
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Michelle M
Frequent Contributor (1K+ posts)
Member # 7200
posted
quote:Originally posted by Nimzovich76: Michelle, is just because you don't understand how these test are done. Do your reading first, understand exactly how they are done. I'm all ears to hear the science behind a Western Blot being more sensitive than an Elisa (at least 4 weeks after exposure), better yet ask your LLMD to write it down for you so that you can post it for me. Guess what, he is not going to do it if he really knows how these tests are done, nobody could claim that a WB is more sensitive than an Elisa, even though they do.
Nimzovich, I don't need my LLMD to write it down for me, because I can read. So can you. Are you getting this foolish advice from a duck, or what? It is SO widely accepted that the ELISA pales in comparison to the western blot it's kind of a non-issue.
Michelle
"The ELISA has been shown to be an unreliable test in many patients with Lyme Disease, both in early infection and later disease (8, 10). Part of the reason for the lack of sensitivity of the ELISA is the use of whole organisms, resulting in a high amount of background absorbance. After correction for the high background, only a small percentage of positives can be detected. Because Western blots separate the proteins of the borrelia, specific reactions can be visualized, and more accurate interpretations of the results made."
[Med Clinics of N. Amer . 86:341-9. 2002] ____________________________________
The usefulness of Western blot in the serological diagnosis of Lyme borreliosis was evaluated compared with an ELISA using a whole cell sonicate antigen.
Fifty-three of 68 (78%) patients with neuroborreliosis had positive IgM and/or IgG immunoblots and 40 of 68 (59%) had positive IgM and/or IgG ELISA titers in serum. Eight of 44 (18%) controls with meningitis/encephalitis of non-borrelia etiology had positive IgM and/or IgG immunoblots and 4 of 44 (9%) had positive IgM and/or IgG ELISA titers in serum.
Western blot was more sensitive than ELISA, the difference being most pronounced in sera from patients with neurological disease for four weeks or less.
The Western Blot tests (IgG and/or IgM) are much more sensitive and specific than the above ELISA tests. With the Western blot, the laboratory can visualize the exact antibodies you are making to the Lyme bacteria. In some cases the laboratory may be able to say that your ``picture of Lyme antibodies'' is consistent with early disease or with persistent/ recurrent disease.
[ILADS] ________________________________________
The ELISA is a poor assay, with marginal sensitivity. The Western Blot is more sensitive. The increased sensitivity of the Western Blot is analogous to a mountain where the base is a Western Blot and the summit is an ELISA. The Western blot has considerably more sensitivity because it provides detection before the peak of the response.
The Western Blot is a qualitative assay based upon the individual visualization of a patient's unique antibody response against the various Borrelia antigens. This type of assay is not restricted by the sensitivity and specificity concerns as the ELISA.
The Lyme enzyme-linked immunosorbent assay (ELISA), which produces a titer of total immunoglobulin G (IgG) and IgM antibodies, is currently the accepted initial screening for suspected Lyme disease.1 This approach should be reevaluated, however, because commercial ELISA tests do not meet the requirement for an effective screening test, due to their low sensitivity. By definition, a screening test should have at least 90% sensitivity, whereas commercial Lyme ELISA tests have a sensitivity of 65% or less.8
The Western blot test, which is commonly used as a confirmatory test for Lyme disease, is more sensitive than the ELISA.
...
* The ELISA test has only 65% sensitivity and is therefore unacceptable as the first step in a two-step screening process for Lyme disease. Screening should begin with the Western blot test.
[Clinical Trends and News in Neurology, CME, by Dr. S.]
Posts: 3193 | From Northern California | Registered: Apr 2005
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Geneal
Frequent Contributor (5K+ posts)
Member # 10375
posted
Interesting thread.
I skipped the Elisa and asked for the Western Blot due to research that indicated the lack of accurate determination of Lyme disease.
It is my health, or lack of, that prompts my decisions. Hopefully a well informed ,concious decision.
I only had one IGM band that was positive at a less than well respected local lab.
That was enough for me as everything, and I mean everything else they tested me for was negative.
I had 64 out of 80 symptoms on a Lyme symptom list.
My LLMD never really even mentioned my WB. I asked if I needed another by Igenex, and he said no. I have a clinical dx. of Lyme, not one that meets CDC guidelines.
I say, do your homework, review the literature. Then decide what you are comfortable with and how you feel.
I could care less if I were CDC positive. I just wanted to be treated.
Geneal
Geneal
Posts: 6250 | From Louisiana | Registered: Oct 2006
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posted
i have a friend who is in cancer research and he told me it is widely known that the current Lyme antibody tests are notoriously inaccurate.
Posts: 127 | From MA | Registered: May 2004
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posted
Western blot was more sensitive than ELISA, the difference being most pronounced in sera from patients with neurological disease for four weeks or less.
this is the best reference that you have in terms of sensitivity between WB and ELISA at early stages of the disease which I did mention in my previous post, the WB may be more sensitive within 4 weeks of exposure but as you can see from this paper the difference is only marginal: 78% for WB compared to 59% of the ELISA and that's again for early stages, before there is a strong antibody reaction, after that the WB is by no means more sensitive than the ELISA.
*******************
you are changing the conclusion of this study. you are saying that this study concludes that the WB is only more sensitive in the first 4 weeks.
that is not the conclusion. the conclusion is that WB is more sensitive overall, but the gap is bigger in the early stages.
Posts: 127 | From MA | Registered: May 2004
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david1097
Frequent Contributor (1K+ posts)
Member # 3662
posted
As far as I am concerned. ELISA IS MORE SENSITIVE THAN WB.... IF ALL OTHER FACTORS ARE EQUAL... HOWEVER...In this case the equalities involved in these tests are somewhat unclear. apparently resulting in the poor clinical corelations between tests and actuial disease.
To add more confussion to this issue. The only elisa lyme test that I know of is a single culture grown strain sonocate. Igenex illudes to the possibility that they do not use a single strain, but rather a multiple strain derived antigen, or at least thats what I can make out. In addition, there are published accounts for differences in strain due to both differencess in culture media AND temperature, both of which are though to affect plasmid activation in the organism.
Based onteh scince and math, Nim. is quite right, ELISA IS more senstive than WB with all other factors being equal. It is the reason that ELISA was thrown out as a single step test for Lyme...the possibility of false positive is greater then for WB but.... it is so cheap that they do it first (this has in no small way also been affected by lobbying from the kit manufacturer/antigen discoverer).
On the other hand, the is considerable clinical experience that clearly shows that the ELISA based tests are not very sensitive when compared to WB???? This is an apparent contradiction.
A little research shows that this does not only apply to Lyme, It also applies to a number of other zoonotic diseases (animal vectored diseases)... in fact I have heard that many veterinarians don't even bother doing ELISA for bacterial infections becuase of its poor diagnostic value, either positive OR negative, The trend is definately towards, low cost PCR (zoologix.com, healthgene.com)~ $50 for a panel!
So given this clinical experience , why is there such a difference in thoery and practice? I can only guess, but one aspect that is rather clear is that ELISA does not have the bennifit of differential discrimination, ie. there are no differntial bands that can be compared aginst each other and against background. The ability to seperate bands from a background is inherently a more sensitive detection method as you now have a dynamic signal with modualtion as compared to a baseline detection that is used for Elisa.
Another possibility is that there are some odd things going on with antibody binding to the antigens, perhaps multiple anibodies attaching to single large sonocate fragements ( then very heavy ones get seperated away from the lighter ones during the electrophoresus in the WB), or binding in such a way to reduce the probability of the dye attaching, in effect tying up more antibody than is expected using the dyeing technique????
I have looked for a very long time trying to see what the complete history of Lyme ELISA has been. It is clear that there has been a process of refinement from the early days, this in effect has increased the specifivity of the ELISA test but in doing so it also appears that there has been a subsequent reduction in sensitivity. The big problem is that there are no details on the refinement process that has been used nor the reasons for the original "over" sensitiviy. Ther are publications on "accuracy" of the new ELISA tests but these are nothing more than promotional ads for one company or the other.
I am sure the problem is known and the causes are known. This is clear from the hype associated with the "C6" petide ELISA for Lyme. These people where quite eager to tell about the deficiencies of the B-13 sonocated derived ELISA. Now even the C6 does not seem to be as good as was advertised (this is a common problem with many many tests being broadcast at many many conferences and journals way before they are fully evaltated... it has something to do with getting sign ups and license fee's on the antigens/test used).
It would be very interesting to pre-filter the sonocate and seperate the correct fragement mass for the anitgens of interest and then use these filtered antigens in an ELISA. A good masters thesis for someone....
On top of all this there is also the setting in which the two different test are run. Acute cases surely use an overwhelming number of ELISA, whereas late stage (and thus anitibody reduced) cases use WB (not even doing ELISA). So even in this regard WB and ELISA cannot be used in direct comparisons
Posts: 1184 | From north america | Registered: Feb 2003
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david1097
Frequent Contributor (1K+ posts)
Member # 3662
posted
Immagine you are testing to see if a picture contains a picture of an elephant. To do this you cut the picture into little pieces , each contains a little bit of the elephant picture. you then try to identify if the picutre had an elephant on by looking at the picture fragemnts. Each little fragment coresponds to a "band".
Elisa basically groups all the fragements into on big pile and says YES or NO, there are or are not enough pieces that contain what looks like an elephant.
WB looks at how many fragments of each type there are and lets you make up your own mind (ie here's a piece of the trunk , anohter of the tail, another of the foot etc.
The "problem" with Elisa is that there might be a lot of pieces that look the the parts of the body of the elephant (ie all grey) and you could say well look how many grey pieces there are, there must be an elephant in the picture.. when in fact you are just seeing a grey sky.... a false positive would result.
You avoid this with WB because you can choose only to look at the parts you want to look at , ie the trunk, foot, tail etc. Thereby avoiding false positives.
Thats how it works in simple terms.It has a direct relationship with the WB tests, for exaple the 41 DKA band is thrown out quite often due to it being hard to distinguish from "grey sky" in the example above but the Elisa, by default cannot offer the same discrimination...
all of this IN THEORY...that the way it is supposed to work, but nothing is that simple in practice.
Posts: 1184 | From north america | Registered: Feb 2003
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