In een commentaar besteedt de Scientific American (zie onder) aandacht aan
een mogelijke link tussen Bartonella
en ME/CVS ("chronic fatigue")
naar aanleiding van een recente studie (zie onderaan)
van Breitschwerdt,
Maggi en collega's
van de North Carolina State University
naar Bartonella-infecties bij mensen met reuma-achtige klachten
die in een gebied wonen waar Lyme relatief constant
(endemisch) voorkomt.
Persbericht:
Voor het persbericht bij de studie gepubliceerd in mei 2012, klik op onderstaand logo:
Samenvatting:
Van de 296 patiënten die door een reumatoloog onderzocht waren,
werden bij 62,5% van de mensen antilichamen tegen
Bartonella henselae, B. koehlerae, or B. vinsonii subsp. berkhoffii gevonden, en
bij 41,1% van de patiënten werd via PCR de aanwezigheid van Bartonella-soorten vastgesteld.
Sommige mensen bleken positief bij serologische testen (antilichamen) maar niet bij PCR-testen,
en omgekeerd, niet alle PCR-positieve patiënten werden antilichamen gevonden.
Vaak kon met PCR ook de Bartonella-(onder)soort vastgesteld worden, maar niet altijd.
De conclusie die hier volgens de onderzoekers uit volgt:
géén enkele enkelvoudige testaanpak is sluitend, een combinatie van testmethoden is essentieel.
Kritiek en weerwoord:
De kritiek van twee onderzoeksgroepen op de studie
en het weerwoord van de auteurs vindt u
hier.
...
Achtergrondinformatie:
Voor meer informatie over Bartonella en Bartonellose en studies van de onderzoeksgroep-
Breitschwerdt en anderen, verwijs ik U graag door naar een aparte pagina over dit onderwerp.
Does the Bacterium behind Cat Scratch Fever Cause Chronic Fatigue?
The microbe that is known to cause cat scratch fever remains cloaked in mystery
By Marissa Fessenden, January 4, 2013
Recent research found fragments of Bartonella species' DNA
in 41 percent of 296 patients examined by a rheumatologist.
...
The findings, published in May 2012 in Emerging Infectious Diseases,
drew criticism in two letters to the editor, published last November
...
Complicating matters is the pathogen's elusive biology:
it evades detection within hosts
by changing proteins on its surface and
by hiding inside blood vessels.
In addition, the organism can shift strategies
depending on whether it is in a mammalian host,
such as a cat or dog, or an insect vector, such as a flea or tick.
"We are not even at the tip of the iceberg"
when it comes to understanding Bartonella,
says Jane Koehler, a professor of medicine at the University of California, San Francisco.
...
http://www.scientificamerican.com/
article.cfm?id=do-the-bacteria-behind-scratch-fever-cause-chronic-fatigue
Enkele relevante citaten uit het studieverslag:
Serologic and BAPGM Findings
Of the 296 patients,
185 (62.5%) were seroreactive to >1 Bartonella sp. antigens and
122 (41.1%) were infected with B. henselae, B. koehlerae, B. vinsonii subsp. berkhoffii or Bartonella spp.
Of the 122 patients with Bartonella spp. infection, PCR results were positive
but DNA sequencing was unsuccessful or did not enable species identification for 29 (23.7%).
After subculture, 6 isolates were obtained from 5 samples:
3 B. henselae isolates, 2 B. koehlerae isolates, and 1 Bartonella sp. isolate
that was not fully characterized.
Of the Bartonella-infected patients,
120 (98.4%) had a positive PCR result
after DNA extraction from blood, serum, or enrichment culture, and
2 (1.6%) had a positive PCR result only after subculture isolation.
For B. henselae,
67 (22.6%) patients were seroreactive and
40 (13.5%) had positive PCR results.
Of these 40 patients,
only 7 (17.5%) were concurrently B. henselae seroreactive,
whereas 33 (82.5%) patients who had a positive PCR result
were not seroreactive to B. henselae antigens.
There was no association
between B. henselae antibodies and bacteremia (p = 0.37).
For B. koehlerae,
89 (30.1%) patients were seroreactive and
54 (18.2%) had positive PCR results.
Of these 54 patients,
24 (44.4%) were seroreactive to B. koehlerae by IFA assay,
whereas 29 (53.6%) were not seroreactive to B. koehlerae antigens.
One patient with a positive B. koehlerae PCR result
did not have a concurrent IFA test result (serum not submitted).
There was an association between B. koehlerae seroreactivity and bacteremia (p = 0.008);
seroreactive patients were more likely to be infected (odds ratio [OR] 2.25 [1.22–4.15]).
For B. vinsonii subsp. berkhoffii,
148 (50.0%) patients were seroreactive by IFA testing to at least 1 of 3 genotypes, and
10 (3.4%) had a positive PCR.
Of these 10 patients,
3 were infected with genotype I, 6 were infected with genotype II, and
for 1 patient the genotype could not be defined on the basis of readable DNA sequence.
Seroreactivity to genotypes I, II, and III was found for
77 (26.0%), 102 (34.5%), and 82 (27.7%) patients, respectively.
There was
no association between B. vinsonii subsp. berkhoffii seroreactivity and bacteremia.
...
It is becoming increasingly clear that
no single diagnostic strategy will confirm infection with a Bartonella sp. in immunocompetent patients.
...
Cats are the primary reservoir hosts for B. henselae and B. koehlerae,
whereas canids, including dogs, coyotes and foxes,
are the primary reservoir hosts for B. vinsonii subsp. berkhoffii.
...
Bartonella spp. bacteremia and rheumatic symptoms
in patients from Lyme disease-endemic region.
Maggi RG, Mozayeni BR, Pultorak EL, Hegarty BC, Bradley JM, Correa M, et al.
Emerg Infect Dis. 2012 May;18(5):783-91. doi: 10.3201/eid1805.111366.
Abstract
Bartonella spp. infection has been reported
in association with an expanding spectrum of symptoms and lesions.
Among 296 patients examined by a rheumatologist,
prevalence of antibodies
against Bartonella henselae, B. koehlerae, or B. vinsonii subsp. berkhoffii (185 [62%]) and
Bartonella spp. bacteremia (122 [41.1%]) was high.
Conditions diagnosed before referral included
Lyme disease (46.6%), arthralgia/arthritis (20.6%), chronic fatigue (19.6%), and fibromyalgia (6.1%).
B. henselae bacteremia was significantly associated with prior referral to a neurologist,
most often for blurred vision, subcortical neurologic deficits, or numbness in the extremities,
whereas B. koehlerae bacteremia was associated with examination by an infectious disease physician.
This cross-sectional study cannot establish a causal link
between Bartonella spp. infection and
the high frequency of neurologic symptoms, myalgia, joint pain, or progressive arthropathy
in this population;
however, the contribution of Bartonella spp. infection, if any,
to these symptoms should be systematically investigated.
The genus Bartonella comprises at least 26 species or subspecies of vector-transmitted bacteria,
each of which has evolved to cause chronic bacteremia in >1 mammalian reservoir hosts.
Among these,
bartonellae of 14 species or subspecies have been implicated in zoonotic diseases
including cat-scratch disease,
which is caused by B. henselae transmission during a cat bite or scratch and
characterized by acute onset of self-limiting fever and regional lymphadenopathy (7–9).
Recent observations, however, are causing a paradigm shift
from the assumption that
infection with a Bartonella sp. consistently induces an acute, self-limiting illness
to the realization that
subsets of infected, immunocompetent patients can become chronically bacteremic.
After B. henselae was confirmed as the primary cause of cat-scratch disease in the early 1990s,
several reports described an association between the newly identified bacterium and
rheumatic disease manifestations,
variously described as rheumatoid, reactive, or chronic progressive polyarthritis.
One study, however, failed to isolate B. henselae
from synovial fluid of 20 patients with chronic arthritis.
Because epidemiologic evidence supports an association
between rheumatic symptoms and cat-scratch disease and
because arthritis is a primary disease manifestation of Borellia burgdorferi infection (Lyme disease),
we explored whether antibodies against and bacteremia with Bartonella spp.
can be detected in patients examined for arthropathy or chronic myalgia.
Our primary objective was to determine
the serologic and molecular prevalence of Bartonella spp. bacteremia
in patients referred to a clinical rheumatologist.
We also compared
self-reported symptoms, health history, and demographic factors with Bartonella spp. bacteremia
as determined by an enrichment blood culture platform
combined with PCR amplification and DNA sequencing, when possible,
to determine the Bartonella species and strain.
http://wwwnc.cdc.gov/eid/article/18/5/pdfs/11-1366.pdf
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