posted
This is exactly what confuses me. After one 30-day course of doxy, I am getting some joint and neuro symptoms (swollen achy fingers & feet, itching and crawly sensations on legs & feet, achy knee) and my dr's response was to order a "lyme titer." When I asked the nurse if this test would be reliable, given I just got off a 30-day course of antibiotics, she said the antibiotics didn't matter. Which I'm pretty sure is wrong. I also asked her about the general issue of false negatives and she said the titer was needed for a "conclusive diagnosis." Even though I had a documented tick bite and bull-s eye rash.
This freaked me out enough that I'm going to try to get an apptmt with a LLMD close to me. Carol
Posts: 56 | From southeastern PA | Registered: Jul 2006
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posted
problem is that I don't have an LLMD anywhere near here, and I'm not breathing well enough to attempt an 11 hour flight. (I was previously living in an area in the US where lyme is widespread)
My information, as yours, is that antibiotics can alter the results of the tests, as well as steroids (which I was taking in considerable doses at the time of testing)
Posts: 169 | From former Philadelphian | Registered: Jun 2006
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Michelle M
Frequent Contributor (1K+ posts)
Member # 7200
posted
Many, MANY chronic lyme patients have negative ELISA's yet HIGHLY positive western blots!! Me included! It's an essentially worthless test, unless you're very lucky.
One study I know of compares it to flipping a coin -- that's how accurate it is.
AM36 and Carol, you're both absolutely correct that antibiotics can skew the results of your western blot. BIG time. IGeneX will tell you that. To get the most accurate blot, they'd have you clear of antibiotics for a couple of weeks, most likely.
Here's what ILADS has to say about it: (From "The Basics" -- at http://www.ilads.org website: {I'm adding white spaces to make it more readable!}
Michelle
__________________________________________________ 6. The ELISA screening test is unreliable. The test misses 35% of culture proven Lyme disease (only 65% sensitivity) and is unacceptable as the first step of a two-step screening protocol. By definition, a screening test should have at least 95% sensitivity.
7. Of patients with acute culture-proven Lyme disease, 20-30% remain seronegative on serial Western Blot sampling. Antibody titers also appear to decline over time; thus while the Western Blot may remain positive for months, it may not always be sensitive enough to detect chronic infection with the Lyme spirochete.
For ``epidemiological purposes'' the CDC eliminated from the Western Blot analysis the reading of bands 31 and 34. These bands are so specific to Borrelia burgdorferi that they were chosen for vaccine development.
Since a vaccine for Lyme disease is currently unavailable, however, a positive 31 or 34 band is highly indicative of Borrelia burgdorferi exposure. Yet these bands are not reported in commercial Lyme tests.
When used as part of a diagnostic evaluation for Lyme disease, the Western Blot should be performed by a laboratory that reads and reports all of the bands related to Borrelia burgdorferi.
Laboratories that use FDA approved kits (for instance, the Mardx Marblot�) are restricted from reporting all of the bands, as they must abide by the rules of the manufacturer. These rules are set up in accordance with the CDCs surveillance criteria and increase the risk of false-negative results.
Posts: 3193 | From Northern California | Registered: Apr 2005
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tabbytamer
Frequent Contributor (1K+ posts)
Member # 3159
posted
My first test was an elisa, which was officially "negative" but . . .
when looking at the actual numbers of the test, it did show what I considered significant Lyme antibody levels--just not enough for it to be consiered a positive.
So I figured, to have that many antibodies, I must have been exposed at some point in time.
Then I found out about IGeneX and had the western blot done.
posted
When I had my initial ELISA test done through quest with my non LLMD it came back positive for lyme. I then met with the LLMD and we sent out to IGENEX and it was positive through them also.
I do know that from reading here and talking with my doctor that ELISA tests are not always accurate and that there are many cases where there are false negatives.
Sending out to IGENEX is a good next step.
~David
-------------------- Same nightmare, different day! Posts: 401 | From East Coast | Registered: Nov 2005
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posted
I think your Dr. was thinking of Igeanix-Western blot witch by comparison,was so much more accurate,that it seemed like false positives.
If he sounds like a Duc... Alan
-------------------- Charter member of the ~ Delux Toasting Club ~ Our Moto: "Take No Prisoners" Posts: 95 | From San Diego | Registered: Nov 2005
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posted
My primary seems to be pretty well up to date about Lyme, compared to most non-LLMD's.
She said I was definitely positive. My Elisa was positive and all the supporting tests supported a DX of Lyme. She's reported me as an official case of Lyme to the CDC.
I guess all the blood tests they did "work together" to give a DX of Lyme. That includes a ANA Titer and othe tests.
Anyway, she's said I am positive for the disease.
Secondly are the symtpoms, which support a clinical diagnosis. The worst of all - the neuro sx.
Anyway, I feel fortunate that my elisa DID come out positive and I can now focus on getting well.
Posts: 47 | From New Mexico | Registered: Jun 2006
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