Xenodiagnosis in Humans to Detect Bb infection

Topics with information and discussion about published studies related to Lyme disease and other tick-borne diseases.
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inmacdonald
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Re: Xenodiagnosis in Humans to Detect Bb infection

Post by inmacdonald » Mon 17 Feb 2014 14:23

The First Human subject should know that "sterility"
in Xenodiagnostic Ticks can NEVER be guaranteed.

Respectfully,
Alan B. MacDonald , MD , FCAP FASCP
Feb 17, 2014

duncan
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Joined: Wed 5 Sep 2012 18:48

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by duncan » Mon 17 Feb 2014 20:22

Tom, we would need to get it sanctioned eventually, if it merits it. I am not surprised that IDSA/NIH/CDC might be reticent about engaging in any direct discussions, let alone outright launching a new study, or folding into an existing one like the one I mentioned above. I am sure few of us are surprised. ;)

I was hoping ILADS might throw support behind it, even if it's only verbal. Maybe there are liabilities involved, or the costs are worrisome. Or maybe, they just really haven't yet given it the attention it seems to deserve. I don't know.

There are other avenues, like crowdsourcing. Look at what the CFS groups are doing to generate financials for efforts off the govt grid. Even Lipkin is getting involved. And the CFS crowd really doesn't have a bonafide central effort that is coordinated (obviously not counting govt "efforts") on behalf of patients and researchers, although Enlander of Mt Sinai in NY is apparently trying to create one. So these new research initiatives are mostly patient driven, and that is a very cool and encouraging thing indeed.

But if one can generate enough interest at the grass roots level, and get some media coverage, it would be hard for the NIH or other research groups - certain academic institutions outside of Yale/Harvard etc? - not to acknowledge the process, and address it - although not necessarily in a good way. Columbia and Stanford come to mind as being open-minded it seems to me.

So, even though that cost of a few hundred dollars is not insurmountable, and can be handled by many of us, we eventually will need a publicly recognized authority to make it stick and resonate. How many compelling studies, big and small, have been performed only to die on the vine because that critical mass of interest, coupled with government participation - and hence accountability - was never achieved?

This is not a reason not to pursue your idea, just trying in a clumsy way to frame it against some of the possible issues confronting it.

Margherita
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Joined: Thu 27 Sep 2012 18:22

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by Margherita » Tue 18 Feb 2014 0:48

AlanMacDonald wrote:
The First Human subject should know that "sterility"
in Xenodiagnostic Ticks can NEVER be guaranteed.
Besides Borrelia, what about transovarial transmission of co-infections?

example:

http://www.openthesis.org/documents/Tra ... 73305.html
or:
http://repository.up.ac.za/handle/2263/17832


LHCTom wrote:

I suspect the NIH, IDSA and ILADS would all decline since I've reached out to a number of them offering to fund a study and received few responses.

Why not trying to find support elsewhere, if necessary involving private institutions (Europe?)?
As a European lymepatiënt I'm really wondering why everything concerning Lyme disease seems to depend exclusively on what the U.S. NIH and IDSA deem to be right or wrong. Why?!
(suppose I'm a little naïf!)

lou
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Joined: Fri 2 Nov 2007 0:41

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by lou » Wed 19 Feb 2014 22:05

But if a byproduct of the process to determine a more accurate diagnostic would be to confirm infection in chronic/PTLDS patients, one would think the NIH would be open to the suggestion.

Are there any studies that have incorporated mRNA in the search for Bb? Maybe, Tom, you want to start a new thread about this process? Like I said: There is an NIH study already underway that this could almost seamlessly fit into, if warranted, and if one could convince Marques and company.
Duncan apparently doesn't understand that NIH and Marques do not want a more accurate diagnostic. They do not want to find more cases or learn that in fact there is a chronic lyme disease. If in more than 15 years her intramural study has failed to help a single lyme patient, then there is no interest in doing this.

duncan
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Re: Xenodiagnosis in Humans to Detect Bb infection

Post by duncan » Fri 21 Feb 2014 18:02

Thank you, lou, for clarifying for me what Marques and the NIH are not looking for in a diagnostic.

Maybe if, as you pointed out, there is no interest in such a venture, instead of bemoaning the situation, an effort towards generating the appropriate interest could be pursued. Last I checked, the NIH is funded by tax payer dollars, and open to public scrutiny.

Knowing someone's politics only counts for so much. You want change? You need dialogue.

dlf
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Joined: Sun 7 Apr 2013 15:36

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by dlf » Sat 22 Feb 2014 16:46

LHCTom wrote:
There would seem to be only one possibility when testing a living human. Search for multiple gene mRNA or RNA transcription products which suggest a viable transcribing organism over a long time period to overcome the mRNA degradation rate and the low re-emergence rate. Or search for large increases in DNA or mRNA over time suggesting the number of organisms is increasing with active division and/or transcription. Since the quantity of DNA or mRNA would be very low, the most sensitive nested real time PCR or reverse transcription to cDNA followed by PCR testing must be done many times to achieve a useful measurement given the low or variable spirochete load. Then this must be done over a period of years to be sure it exceeds the re-emergence rate.
AND
But the RT-PCR process is less sensitive than the best nested real time PCR testing so it might also be just as practical to use this approach and look for a quantitative increases in DNA over time. This would be to look for re-emergence. The simple presence of DNA does not prove viability. But performing the PCR many many times over a long period would be able to show an increase in DNA presence. The only way DNA presence can increase is if the organism is dividing and is therefore viable. The same would be true for mRNA. DNA lasts a long time but DOES NOT increase unless its sourced from a dividing living viable organism. This gets over the "its just debris" like the 5000 year old iceman story. Mots sources say mRNA has a very short half life and the approach has been used successfully.
AND
At $150 per test with sequencing, it would be possible and practical to choose the right PTLDS candidate(s) and run the test say 3 times ( to increase the odds) every 3 months for 2 years. That is 3 x $150 = $450 * 4 ( times a year) * 2 (years) = $3600. The ALS culture with sequencing is over $1000 and has validation problems. The low temperature nested PCR is solidly validated and commonly used. Based on the paper, if DNA was found and sequenced, the genotype could be verified as un-changing and contamination ruled out by "proper" diversity and its should be possible to quantify the amount of DNA found to check for viability. This of course is the poor mans study but if successful, might tempt a non-entrenched researcher to implement it more completely and carefully. Any volunteers? if I pay for it?
AND
Yes it needs to be easy and coordinated. My doctor's clinic will draw the blood and send it out for $50. That means running say 3 tests on one draw to increase the odds is only $400 ( 3 x $150 + $50) while a single test is $200. If it was going to be done, it would important to have access to a clinic with a reasonable draw fee and a doctor willing to coordinate with other candidate doctors over a 2 year period. Any less time and I believe it wouldn't be useful. That way the results could be reported in a coordinated fashion. Believe it or not, my Kaiser lab will do the draw for free and send it out as long as I have my outside doctors lab requisition. I'm actually planning on doing this for myself and see what happens.
Let me preface my comments by stating the obvious........I am NOT a scientist.

However, it would seem to me that in order to prove resurgence using this as a method, one would need to remain off antibiotics for the entire length of the study. I suspect that LHCTom is correct in saying that it would require a two year period. That is a very long time to expect patients to refrain from taking all antibiotics. Especially, given the immune dysfunction that many Lyme sufferers experience, and the number that end up with opportunistic infections, that would be an awful lot to ask.

Another issue I forsee relates to the number of spirochetes in the sample, if they are too low, it would appear that they may not be detected.

http://ajcp.ascpjournals.org/content/133/4/569.full
Increased Sensitivity and Specificity of Borrelia burgdorferi 16S Ribosomal DNA Detection

The nested PCR testing validated by Sanger DNA sequencing provides reliable in vitro information for physicians in the management of early Lyme disease and possible chronic Borrelia infections, especially when the results of the serologic tests are ambiguous. However, this PCR-based test may fail to identify B burgdorferi–infected samples when the number of spirochetes in the sample is less than 1,000/mL. Therefore, it does not replace the established serologic tests that have proven useful in support of the clinical diagnosis of Lyme disease in most cases.
Another thing I haven't looked into is whether the 16S ribosome would have variable components. If there are any proteins that would be subject to antigenic variability, there could be a problem with identifying the spirochete offspring as being the same as the parent.
Just a few thoughts......

Pandora
Posts: 252
Joined: Tue 20 Mar 2012 14:58

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by Pandora » Mon 24 Feb 2014 7:40

WHY are they spending YOUR money, looking for a test to detect gene sharing stealth infections? IF THAT WAS INDEED WHAT THEY WERE UP TO?

Do you NOT believe they gave it to all of us for decades in infective immortal cell lines, now being carried generations to the 1 in 29 now being born severely multiply infected called Autisms, and all the rest of you will get your syndromes all in good time as more infections and infectious junk DNA is added to the mix?

Or you might get lucky and just fall over with a heart attack OR stroke.

But rest assured they need NOT spend one cent more of our money looking for tests to deny you treatment.....BECAUSE THEY GAVE IT TO US ALL FOR DECADES.

Move their assets to treatments and preventions now to stop Our Age of Syndromes.

http://vimeo.com/9581140
------------------------------
First, Do No Harm: How We Failed Justina Pelletier and Her Family
http://www.huffingtonpost.com/cristy-ba ... 43997.html

BCH's and Tufts Ethical Persuasion also involves kidnapping kids for over a yr. diagnosed with PSYCH.

http://www.childrenshospital.org/~/medi ... State.ashx

Linden T. Hu, MD
Xenodiagnosis of Lyme Disease in Humans

Professor, Tufts University School of Medicine
http://www.lymediseaseassociation.org/i ... nce-agenda

I hope you all get out and attend!!! Be sure and ask them why we have had over 88,000 Soldiers suicides, at the rate of 22 a day avg. now, since they introduced Anthrax and Smallpox vaccines to the mix! Still wondering how the "ETHICAL" approval to dole it out to 70 US facilities for childrens vaccine is working out!
--------------
YOU don't need a xenodiagnosis. You need only to have symptoms----because they gave it to all of us FOR DECADES in infectious vaccines. In Henrietta Lacks IMMORTAL cells used for ALL vaccines when Harvard KNEW she had chronic Syphilis.
http://vimeo.com/9581140
Last edited by Pandora on Tue 25 Feb 2014 0:26, edited 4 times in total.

admin
Site Admin
Posts: 342
Joined: Wed 25 Jul 2007 21:06

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by admin » Mon 24 Feb 2014 13:49

Please stay on-topic, which is defined by the opening post and topic title.

Further, since this is in the "Science" section, the information and discussion should be based on medical science.

RitaA
Posts: 2768
Joined: Thu 1 Jul 2010 8:33

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by RitaA » Fri 28 Feb 2014 21:15

http://www.reuters.com/article/2014/02/ ... D720140228
Tick test for persistent Lyme disease tried in humans

By Kathryn Doyle

NEW YORK Fri Feb 28, 2014 11:29am EST

(Reuters Health) - A small experiment to see whether uninfected ticks could "diagnose" a lingering Lyme infection in people produced modest results, researchers say.

DNA from the Lyme parasite, but not live parasites themselves, were transmitted to the ticks from just two people out of two dozen who had persistent Lyme symptoms despite treatment.

In animal studies, researchers have successfully used "xenodiagnosis," or diagnosis with another animal, to detect the signs of a persistent Lyme infection in the blood. The technique has also worked in people to detect another parasitic infection, Chagas disease.

But the new report, published in Clinical Infectious Diseases, describes the first attempt to use xenodiagnosis for Lyme disease.

"This is a very initial study, our main objective was to develop the technique in humans," lead author Dr. Adriana Marques of the National Institutes of Health in Bethesda, Maryland, told Reuters Health.

"It is very hard to find evidence of the bacteria itself, not just antibodies, in infected people once the skin rash is gone," she said. This tick method may make that process a bit easier, but only with further research, she said.


For most people who contract Lyme disease, a couple of weeks of antibiotics clear up the infection easily. About four weeks later, patients with no signs of the infecting bacteria in their blood get a clean bill of health.

But 10 to 20 percent of people who get Lyme disease, which is transmitted through a bite from an infected tick, continue to report having pain, fatigue or aches even when it appears the infection is gone.

The symptoms can last for more than six months and are called Post-Treatment Lyme Disease Syndrome(PTLDS).

In animal tests, mice and monkeys have been infected with Lyme disease then treated until no Lyme bacteria were detectable in their blood. If at that point an uninfected tick bit the animal and Lyme bacteria turned up in the tick, it meant the animal was actually still carrying the infection.

For the new study, researchers tried out the second-bite system on people with PTLDS. Of the 36 participants, 26 had either persistent symptoms after Lyme disease treatment, or still had an itchy, red lesion at the site of the original bite, or had unusually high levels of antibodies against the infection even though treatment seemed to have been successful.

The other ten volunteers were healthy and had never had Lyme disease.

Researchers placed 25 to 30 uninfected ticks on the arm of each person to feed, under a special dressing, and collected the ticks a few days later.

The ticks were then incubated for up to two weeks to allow any potentially transmitted Lyme bacteria to develop, and afterwards researchers did a variety of molecular tests looking for any sings of the bacteria.

None of the ticks from healthy volunteers had evidence of the Lyme bacteria. Researchers successfully harvested usable ticks from 23 participants with a history of Lyme, and 21 had no ticks test positive for signs of bacteria.

For another two people the results were unclear. For one person with persistent symptoms after antibiotic treatment and one person with a persistent rash who had just started antibiotics, the ticks did test positive for fragments of DNA from the bacterium.

"The next step will be to see if the results correlate with persistent symptoms. We can't answer that question right now," Marques said. Right now it doesn't mean anything for the patients' health one way or the other that bacterial DNA was present.


The main objective of the study was to see if this type of xenodiagnosis is safe and appropriate for humans, and the answer seems to be yes since the major complaint from subjects was mild itching, said Justin D. Radolf of the University of Connecticut Health Center in Farmington.

"But the results don't change our understanding of PTLDS," said Radolf, who wrote an editorial accompanying the study.

"There is consensus that post-Lyme disease syndrome as defined in the paper does exist and that it occurs in a minority of people," said Linda K. Bockenstedt of Yale University School of Medicine in New Haven, Connecticut, who coauthored the editorial. "We do not know why this occurs, and the reasons may not be the same for everyone."

The subject is controversial because "chronic Lyme disease" can describe a number of conditions and a constellation of symptoms in people who may never actually have been infected with the bacteria.

"Many chronic Lyme disease patients have been assigned the diagnosis based on symptoms only (not objective signs), and through either misinterpretation of appropriately conducted Lyme (blood tests) or the use of nonvalidated tests," Bockenstedt told Reuters Health in an email.

That could mean that "chronic Lyme disease" is being used as a catchall when in fact another medical condition might underlie the symptoms.

It's hard to say how useful this technique actually is in humans for Lyme disease, Bockenstedt and Radolf write in the journal. The only way to diagnose a persistent infection is by finding live bacteria, which this test did not.

SOURCE: bit.ly/1cPZLio Clinical Infectious Diseases, online February 11, 2014.

Claudia
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Location: Connecticut, USA

Re: Xenodiagnosis in Humans to Detect Bb infection

Post by Claudia » Fri 28 Feb 2014 21:30

from article "Tick test for persistent Lyme disease tried in humans"

By Kathryn Doyle

NEW YORK Fri Feb 28, 2014 11:29am EST



For most people who contract Lyme disease, a couple of weeks of antibiotics clear up the infection easily. About four weeks later, patients with no signs of the infecting bacteria in their blood get a clean bill of health.
Huh? What are "no signs?" What type of blood work?
Last edited by Claudia on Fri 28 Feb 2014 21:33, edited 1 time in total.

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