Below you will find two studies about the persistence of Borrelia burgdorferi, post antibiotic treatment. Study results on this topic are becoming more and more significant as the battle heats up between the IDSA and ILADS doctors over the issue of whether or not Lyme disease is easily treated and eliminated from the human body. I would think the best collection of this literature would be found in Richard Horowitz's new book, "Why Can't I Get Better?" I believe I heard him say on national television a couple of months ago that he had over 100 references to post-treatment Bb persistence in his book. However, as newer studies come out I will continue to reprint them here. Be sure to click through to the actual studies. There is much more information on the source sites, of course. -Bob
Viable but Nonculturable Bacteria
By: Jvo Siegrist, Microbiology Focus Edition 1.4
Product Manager Microbiology…. ivo.siegrist@sial.com
In many specimens, more bacteria are present than we can detect with common cultural methods.
The expression "viable but nonculturable" (VNC) bacteria, describes cells that cannot normally be cultured. However this makes little sense, when one considers that the demonstration of culturability remains the best practically acceptable definition of viability. So a better explanation of the status of these bacteria would be "not immediately culturable". In most cases the non-spore-forming bacteria is in a survival state (e.g., resting, dormancy, quiescence, or debilitation) and the metabolic pathways are still active but the organism are not growing. According to the latest VNC definition, VNC cells are regarded as viable and potentially replicative, but the methods required for resuscitation are beyond our current knowledge. With special media or with certain supplements it has been shown that it is possible to recover them. VNC bacteria have often undergone a treatment like heating, drying, setting under high osmotic pressure (high salt content) or contact with inhibiting chemicals. The end result of the treatment is sensitive cells or sub-lethally damaged cells, which can mean the loss of some ribosomes, damaged enzymes, cell membranes and other problems causing malfunctions in cells.In the recent years species of Vibrio cholerae, E. coli, Campylobacter jejuni, Salmonella spp., Listeria monocytenenes and Yersinia enterocolitica have been reported to enter the viable but nonculturable (VNC) state [1-10].
Supplementing the pre-enrichment and enrichment broths with ferrioxamine E significantly improved the recovery of Salmonella, Cronobacter spp., Staphylococcus aureus and Yersinia enterocolitica from artificially or naturally contaminated foods [1-3]. A concentration of ferrioxamine E (available from Sigma, see Table 2) in the range of 5-200 ng/mL supports growth (see Table 1). Ferrioxamine E provides the essential micro-nutrient iron (III) to the organisms. This leads to a reduced lag-phase in the medium and reactivates damaged bacteria. The ferrioxamine E is often used in Buffered Peptone Water the medium recommended by the ISO-Norms for Enterobacteriacea (see Table 2). The motility of Salmonella is also improved which helps to improve the identification by semisolid selective motility media like MRSV, DIASSALM or SMS. It is recommended when isolating small quantities of cells from dried powders like tea, spices, dried fruits etc. Ferrioxamine E is semi-selective, as it does not improve growth of E. coli, Shigella, Proteus, Providencia and Morganella species.
from this website:
http://www.sigmaaldrich.com/technical-documents/articles/microbiology-focus/viable-but-nonculturable.html
Research Article
Resurgence of Persisting Non-Cultivable Borrelia burgdorferi following Antibiotic Treatment in Mice
- Emir Hodzic mail,
- Denise Imai,
- Sunlian Feng,
- Stephen W. Barthold mail
- Published: January 23, 2014
- DOI: 10.1371/journal.pone.0086907
Abstract
The agent of Lyme borreliosis, Borrelia burgdorferi, evades host immunity and establishes persistent infections in its varied mammalian hosts. This persistent biology may pose challenges to effective antibiotic treatment. Experimental studies in dogs, mice, and non-human primates have found persistence of B. burgdorferi DNA following treatment with a variety of antibiotics, but persisting spirochetes are non-cultivable. Persistence of B. burgdorferi DNA has been documented in humans following treatment, but the significance remains unknown. The present study utilized a ceftriaxone treatment regimen in the C3H mouse model that resulted in persistence of non-cultivable B. burgdorferi in order to determine their long-term fate, and to examine their effects on the host. Results confirmed previous studies, in which B. burgdorferi could not be cultured from tissues, but low copy numbers of B. burgdorferi flaB DNA were detectable in tissues at 2, 4 and 8 months after completion of treatment, and the rate of PCR-positive tissues appeared to progressively decline over time.
However, there was resurgence of spirochete flaB DNA in multiple tissues at 12 months, with flaB DNA copy levels nearly equivalent to those found in saline-treated mice. Despite the continued non-cultivable state, RNA transcription of multiple B. burgdorferi genes was detected in host tissues, flaB DNA was acquired by xenodiagnostic ticks, and spirochetal forms could be visualized within ticks and mouse tissues by immunofluorescence and immunohistochemistry, respectively. A number of host cytokines were up- or down-regulated in tissues of both saline- and antibiotic-treated mice in the absence of histopathology, indicating host response to the presence of non-cultivable, despite the lack of inflammation in tissues.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0086907
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