C6 ELISA

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ChronicLyme19
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C6 ELISA

Post by ChronicLyme19 » Sun 14 Jun 2015 17:50

Ok, so maybe someone can direct me to the right thread, as I'm sure this has probably been discussed before, but anyone had a good explanation of C6 ELISA levels and how they change over time? I can't seem to find the right thread.

So I know this is just another immune marker test, which means you can never conclusively use it to delineate active vs past infection, but my question is, is there a certain limit in which they think if it's high enough the infection is probably still active or recent? I figure if it's low, it could be because the infection is dormant or resolved or it's suppressed your immune system. But is there some threshold above which there's a reasonably strong chance that it shows it's active because it's so high?
Half of what you are taught is incorrect, but which half? What if there's another half missing?

duncan
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Re: C6 ELISA

Post by duncan » Sun 14 Jun 2015 19:10

One of my favorite subjects.

Ok, this has so many rippling repercussions. If you read most descriptions relating to the accuracy the CDC's 2T diagnostic scheme prior to the C6 marketing blitz...then see how all of a sudden there appeared purported weaknesses or limitations to the 2T pointed out by some from the same camp....well, it might be construed as a kind of a fascinating exercise in contradiction,imo.

When the C6 was first being promoted, some marketing campaigns lauded its efficacy both in acute and late stages. Now, not so much. Could it be that levels remained elevated or even rose with some, e.g. late stage patients, even AFTER treatment, and C6 advocates who were also IDSA Guidelines proponents could not easily explain away data like that? I'm not sure.

Irrespective of that possibility, the C6 is mostly promoted these days as a good metric for uncovering acute Bb infections, and then tracking treatment success through following its values. As you know, it's being groomed as a possible replacement to the traditional ELISA (at one time it was also being heralded as a replacement to the entire 2T system).

Not sure if it can be used to discriminate between active or resolved or latent infections outside of acute cases. I am not familiar with it being used or approved for this function. It certainly is being used in acute case, first to diagnose prior to a WB, then to track treatment success through declining values - again, for acute cases.

Personally, if the C6 comes up positive, I treat it as an active infection. You may wish to give Immunetics a call and ask them about what their opinion is of an elevated C6 value in late disseminated...pre- and post-treatment.

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ChronicLyme19
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Re: C6 ELISA

Post by ChronicLyme19 » Sun 14 Jun 2015 21:52

duncan wrote:Irrespective of that possibility, the C6 is mostly promoted these days as a good metric for uncovering acute Bb infections, and then tracking treatment success through following its values. As you know, it's being groomed as a possible replacement to the traditional ELISA (at one time it was also being heralded as a replacement to the entire 2T system).
I can confirm that's still the case. Our county health department people said they are pushing to get the C6 included in the case definition.

I've never been tested with the C6, but I'd be curious to see what it comes up. One of the members of our group in town tested positive through C6 after years of failed westernblots or just one or two bands. She's started in on antibiotics and is herxing so I would say in this case it was an active infection.

You don't happen to know what they claim the false positive/false negative rate is? Insurance companies are covering it, where as you have to pay out of pocket for IGeneX.
Half of what you are taught is incorrect, but which half? What if there's another half missing?

duncan
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Joined: Wed 5 Sep 2012 18:48

Re: C6 ELISA

Post by duncan » Sun 14 Jun 2015 22:26

I don't, but I bet more than one person on this forum does. :)

The same usual caveats I would think hold true about the risk of false negatives - e.g., wrong species/strain, IgM issues, sensitivity problems potentially, etc. I am sure, too, there are false positives, but I dunno...Like I said, for me, as long as I test positive on that C6, I am treating it as active.

I always like to contact the lab people at diagnostic companies...

You can google it, too. There are a ton of papers on the C6, many from the usual suspects.

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