Bartonella fatalities due to Endocarditis

Topics with information and discussion about published studies related to Lyme disease and other tick-borne diseases.
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Joe Ham
Posts: 489
Joined: Fri 27 Jul 2007 6:15
Location: New Mexico, USA

Bartonella fatalities due to Endocarditis

Post by Joe Ham » Mon 26 May 2008 20:42

Infective Endocarditis due to Bartonella spp. and Coxiella burnetii

Volume 1078 published October 2006
Ann. N.Y. Acad. Sci. 1078: 215–222 (2006). doi: 10.1196/annals.1374.123

Experience at a Cardiology Hospital in São Paulo, Brazil
Heart Institute (InCor.HC.FMUSP) of University of São Paulo School of Medicine, Av. Dr. Enéias de Carvalho Aguiar, 44, Pinheiros, São Paulo, Brazil CEP 05403–000 b Adolfo Lutz Institute, São Paulo-Brazil, Av. Dr. Arnaldo, 355 Cerqueira Cesar, São Paulo, Brazil CEP 01246–902

Address for correspondence: Rinaldo Focaccia Siciliano, Rua Cardoso de Almeida 1006/apto13, Perdizes, São Paulo/Brazil CEP 05013-001. Voice: 55-11-38011724; fax: 55-11-30695349. e-mail: rinaldo_focaccia@uol.com.br

ABSTRACT
Bartonella spp. and Coxiella burnetii are recognized as causative agents of blood culture–negative endocarditis (BCNE) in humans and there are no studies of their occurrences in Brazil. The purpose of this study is to investigate Bartonella spp. and C. burnetii as a causative agent of culture-negative endocarditis patients at a cardiology hospital in São Paulo, Brazil. From January 2004 to December 2004 patients with a diagnosis of endocarditis at our Institute were identified and recorded prospectively. They were considered to have possible or definite endocarditis according to the modified Duke criteria. Those with blood culture–negative were tested serologically using the indirect immunofluorescent assay (IFA) for Bartonella henselae, B. quintana, and C. burnetii. IFA-IgG titers >800 for Bartonella spp. and C. burnetii were considered positive.

A total of 61 patients with endocarditis diagnosis were evaluated, 17 (27%) were culture-negative. Two have had IgG titer greater than 800 (≥3,200) against Bartonella spp. and one against C. burnetii (phase I and II≥6,400).

Those with Bartonella-induced endocarditis had a fatal disease.
Necropsy showed calcifications and extensive destruction of the valve tissue, which is diffusely infiltrated with mononuclear inflammatory cells predominantly by foamy macrophages. The patient with C. burnetii endocarditis received specific antibiotic therapy. Reports of infective endocartitis due to Bartonella spp. and C. burnetii in Brazil reveal the importance of investigating the infectious agents in culture-negative endocarditis.

http://www.annalsnyas.org/cgi/content/a ... 1078/1/215

Joe Ham
Posts: 489
Joined: Fri 27 Jul 2007 6:15
Location: New Mexico, USA

Re: Bartonella fatalities due to Endocarditis

Post by Joe Ham » Thu 9 Apr 2009 19:03

Applied and Environmental Microbiology, October 2007, p. 6045-6052, Vol. 73, No. 19
0099-2240/07/$08.00+0 doi:10.1128/AEM.00228-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Mixed Infections, Cryptic Diversity, and Vector-Borne Pathogens: Evidence from Polygenis Fleas and Bartonella Species
http://aem.asm.org/cgi/content/full/73/19/6045#R25

Patrick Abbot, et al

ABSTRACT

Coinfections within hosts present opportunities for horizontal gene transfer between strains and competitive interactions between genotypes and thus can be a critical element of the lifestyles of pathogens. Bartonella spp. are Alphaproteobacteria that parasitize mammalian erythrocytes and endothelial cells.
Their vectors are thought to be various biting arthropods, such as fleas, ticks, mites, and lice, and they are commonly cited as agents of various emerging diseases.
Coinfections by different Bartonella strains and species can be common in mammals, but little is known about specificity and coinfections in arthropod vectors.

We surveyed the rate of mixed infections of Bartonella in flea vectors (Polygenis gwyni) parasitizing cotton rats (Sigmodon hispidus) in which previous surveys indicated high rates of infection. We found that nearly all fleas (20 of 21) harbored one or more strains of Bartonella, with rates of coinfection approaching 90%.

A strain previously identified as common in cotton rats was also common in their fleas. However, another common strain in cotton rats was absent from P. gwyni, while a rare cotton rat strain was quite common in P. gwyni. Surprisingly, some samples were also coinfected with a strain phylogenetically related to Bartonella clarridgeiae, which is typically associated with felids and ruminants. Finally, a locus (pap31) that is characteristically borne on phage in Bartonella was successfully sequenced from most samples. However, sequence diversity in pap31 was novel in the P. gwyni samples, relative to other Bartonella previously typed with pap31, emphasizing the likelihood of large reservoirs of cryptic diversity in natural populations of the pathogen.


INTRODUCTION

Most host populations harbor more than one pathogen strain at a given time, leading to mixed infections or "coinfections" in individual hosts (10, 26, 48).
Unfortunately, there are gaps in our understanding of within-host pathogen interactions. The problem is particularly acute in vector-borne diseases, where little is known regarding mixed infection interactions in natural populations of the vectors themselves. Rather, with only a few notable exceptions (e.g., reference 25), most population-level or clinical data on mixed infections derive from human studies or other mammalian models. The distinction is crucial because of the role that vectors play in pathogen transmission.

The bacterial pathogen Bartonella sp. has become one of a few model organisms for studying the evolution and ecology of vector-borne diseases (28). This is due to diverse efforts to describe Bartonella biology at multiple levels, from cells and immune systems (12, 13, 14, 30), to populations and communities (31, 32), to species and clades (36, 44). The recent publication of full genome sequences is obviously key (2). Bartonella sp. is a short, gram-negative, fastidious bacterium belonging to the Alphaproteobacteria (1).

Closely related to Brucella spp., Bartonella organisms are parasites of mammalian erythrocytes and endothelial cells (12, 13, 14) and are transmitted by blood-feeding insects, such as ticks, fleas, lice, and flies (9, 19, 20, 21, 23, 28).
Infection of a host causes chronic bacteremia and creates a reservoir for vectors that can transmit the bacteria to new susceptible hosts. While prolonged bacteremia is normally associated with severe sickness in a susceptible host, Bartonella-caused bacteremia typically remains asymptomatic in the reservoir host. Some bartonellae are known to be transmitted by the bite (anterior station transmission) or in the feces (posterior station transmission) of insect vectors. For example, in humans, Bartonella bacilliformis, which causes Oroya fever (verruga peruana, or Carrion's disease) in Andean South America is transmitted by the bites of infectious sandflies (5), and Bartonella quintana, which causes trench fever in many parts of the world, is transmitted via the feces of infected body lice (21). Fleas infected with Bartonella henselae (the causative agent of cat scratch disease and of related conditions such as bacillary angiomatosis [30]) and other bartonellae appear to transmit these agents via their infectious feces (9, 19, 20).

Current phylogenetic information indicates six distinct groups worldwide, of which all but one are found in the United States (44). Host and vector affiliations are complex, and the evidence is against strict one-to-one host specificity (28, 32, 33). A consistent trend is that groups of Bartonella species tend to be restricted to natural groups of mammalian hosts (rodents, cats, dogs, humans, etc.), indicating a diffuse but long-term coevolutionary history.

We surveyed the incidence of mixed Bartonella infections in natural populations of the flea Polygenis gwyni parasitizing the Eastern woodrat (Neotoma floridana) and the hispid cotton rat (Sigmodon hispidus). Previous surveys of mammalian hosts indicated that mixed infections of Bartonella can be common (22). An intensive survey of S. hispidus in the southeastern United States, for example, revealed that this host exhibits a particularly high infection prevalence overall, as well as nonnegligible rates of coinfection (33). There is little comparable information on mixed infection rates in Bartonella vectors (49).

However, with mammalian host populations multiply infected with strains that are vectored by insects with generalist host affiliations (e.g., ticks and fleas), the expectation is that rates of mixed infections in competent vectors should be quite high.
The relevance of whether or not this is the case not only bears on the basic natural history and disease dynamics of Bartonella but also on the pattern and tempo of disease emergence (5). Bartonella has been described as the consummate "versatile pathogen" (27) for the breadth of its host affiliations and plasticity of its lifestyles (2). Population-level data are necessary supplements to evolutionary inferences about the genus, because retrospective analyses of such events as lateral gene transfer (4) can become forward-looking and predictive when accompanied by real-time data on the ecological context for such events (15, 24, 34, 47, 55).

[...]

DISCUSSION

Because we surveyed in a manner that discriminated between single and mixed infections in fleas, we also estimated the fraction of fleas harboring more than one Bartonella isolate and the phylogenetic affinities of coinfecting isolates. We found four noteworthy results.

First, the prevalence of Bartonella was surprisingly high, exceeding characteristic records from various putative arthropod vectors (35, 49, 54).
...
Second, we found substantial rates of mixed Bartonella infections. More than half of the fleas we surveyed were infected by more than one Bartonella gltA genotype (Table 2).
...
Third, we successfully amplified a fragment similar to the heme-binding pap31 in fleas evidently infected with B. vinsonii-like isolates (as determined by gltA). This is notable, because in both B. quintana and B. henselae, pap31 is generally known to be phage-borne and orthologous to a large family of heparin-binding protein-coding genes (hbp) critical to heme acquisition, cellular adhesion, and possibly pathogenesis (8, 11, 56).
...
the fourth and perhaps most surprising result was the presence in two fleas of an isolate sharing >94% gltA similarity to B. clarridgeiae and the newly described species B. rochalimae...
B. clarridgeiae is one of the few flagellated bartonellae (51) and has long been a problematic species because of its uncertain phylogenetic placement and the odd host range that it shares with B. bovis (44). It may not be a coincidence that an isolate resembling these hyper-generalist species has been discovered in Polygenis. Efforts to understand the molecular basis of variation in host specificity in the genus (2) would benefit from closer examination of B. clarridgeiae and its relatives (18).[/quote]

From reference 51.
...and immunoblot analysis indicated that the flagellar filament is mainly composed of a polypeptide with a mass of 41 kDa.
...B. clarridgeiae FlaA is thus antigenic and expressed in vivo, providing a valuable tool for serological testing.
Some references from the above
Avidor, B., Graidy, M., Efrat, G., Leibowitz, C., Shapira, G., Schattner, A., Zimhony, O., Giladi, M. (2004). Bartonella koehlerae, a New Cat-Associated Agent of Culture-Negative Human Endocarditis. J. Clin. Microbiol. 42: 3462-3468

Chomel, B. B., Wey, A. C., Kasten, R. W. (2003). Isolation of Bartonella washoensis from a Dog with Mitral Valve Endocarditis. J. Clin. Microbiol. 41: 5327-5332

Chomel, B. B., Mac Donald, K. A., Kasten, R. W., Chang, C.-C., Wey, A. C., Foley, J. E., Thomas, W. P., Kittleson, M. D. (2001). Aortic Valve Endocarditis in a Dog Due to Bartonella clarridgeiae. J. Clin. Microbiol. 39: 3548-3554

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