Molecular Evidence of Perinatal Transmission of Bartonella vinsonii subsp. berkhoffii and Bartonella henselae to a Child

Bartonella vinsonii subsp. berkhoffii, Bartonella henselae, or DNA of both organisms was amplified and sequenced from blood, enrichment blood cultures, or autopsy tissues from four family members. Historical and microbiological results support perinatal transmission of Bartonella species in this family. It is of clinical relevance that Bartonella spp. may adversely influence human reproductive performance.     

Molecular characterization of Bartonella vinsonii subsp. berkhoffii genotype III

The molecular characterization of a Bartonella vinsonii subsp. berkhoffii genotype III strain (NCSU strain 06-CO1) isolated from the blood of a military working dog diagnosed with endocarditis is reported in this study. Several genes were amplified and sequenced for comparative sequence similarity with other strains.     

Bartonella vinsonii subsp. berkhoffii as an agent of afebrile blood culture-negative endocarditis in a human

We report a case of endocarditis in a human infected with Bartonella vinsonii subsp. berkhoffii, which causes bacteremia and endocarditis in dogs. Bacterial identification was established by PCR amplification and sequencing of an intergenic spacer region (ITS1), 16S ribosomal DNA, and a gene encoding citrate synthase (gltA). Bartonella antibodies were detected by immunofluorescence.     

Molecular characterization of the sucB gene encoding the immunogenic dihydrolipoamide succinyltransferase protein of Bartonella vinsonii subsp. berkhoffii and Bartonella quintana

Members of the genus Bartonella have historically been connected with human disease, such as cat scratch disease, trench fever, and Carrion's disease, and recently have been recognized as emerging pathogens causing other clinical manifestations in humans. However, because little is known about the antigens that elicit antibody production in response to Bartonella infections, this project was undertaken to identify and molecularly characterize these immunogens. Immunologic screening of a Bartonella vinsonii subsp. berkhoffii genomic expression library with anti-Bartonella antibodies led to the identification of the sucB gene, which encodes the enzyme dihydrolipoamide succinyltransferase. Antiserum from a mouse experimentally infected with live Bartonella was reactive against recombinant SucB, indicating the mounting of an anti-SucB response following infection. Antigenic cross-reactivity was observed with antiserum against other Bartonella spp. Antibodies against Coxiella burnetti, Francisella tularensis, and Rickettsia typhi also reacted with our recombinant Bartonella SucB. Potential SucB antigenic cross-reactivity presents a challenge to the development of serodiagnostic tests for other intracellular pathogens that cause diseases such as Q fever, rickettsioses, brucelloses, tularemia, and other bartonelloses.     

Bartonella henselae and Bartonella elizabethae as potential canine pathogens

Bartonella henselae or Bartonella elizabethae DNA from EDTA-anticoagulated blood samples obtained from four dogs was amplified and sequenced. The results showed that B. elizabethae should be added to the list of Bartonella species (i.e., B. vinsonii subsp. berkhoffii, B. henselae, and B. clarridgeiae) that are currently recognized as infectious agents in dogs. Furthermore, these results may have potential zoonotic implications, particularly if dogs can serve as a previously unrecognized reservoir for B. henselae. Although the clinical relevance of these observations remains to be determined, it is possible that molecular diagnostic techniques such as PCR may help to implicate a spectrum of Bartonella spp. as a cause of or a cofactor in chronic canine and human diseases of poorly defined causation.     

Bartonella quintana and Bartonella vinsonii subsp. vinsonii bloodstream co-infection in a girl from North Carolina,USA

Medical Microbiology and Immunology - The genus Bartonella consists of globally distributed and highly diverse alpha-proteobacteria that infect a wide-range of mammals. Medically, Bartonella spp....     

Isolation of Bartonella vinsonii subsp. berkhoffii Genotype II from a Boy with Epithelioid Hemangioendothelioma and a Dog with Hemangiopericytoma

In this report, we describe isolation of Bartonella vinsonii subsp. berkhoffii genotype II from a boy with epithelioid hemangioendothelioma and a dog with hemangiopericytoma. These results suggest that B. vinsonii subsp. berkhoffii may cause vasoproliferative lesions in both humans and dogs.     

Coyotes (Canis latrans) as the reservoir for a human pathogenic Bartonella sp.: molecular epidemiology of Bartonella vinsonii subsp. berkhoffii infection in coyotes from central coastal California

Bartonella vinsonii subsp. berkhoffii was originally isolated from a dog suffering infectious endocarditis and was recently identified as a zoonotic agent causing human endocarditis. Following the coyote bite of a child who developed clinical signs compatible with Bartonella infection in Santa Clara County, Calif., this epidemiological study was conducted. Among 109 coyotes (Canis latrans) from central coastal California, 31 animals (28%) were found to be bacteremic with B. vinsonii subsp. berkhoffii and 83 animals (76%) had B. vinsonii subsp. berkhoffii antibodies. These findings suggest these animals could be the wildlife reservoir of B. vinsonii subsp. berkhoffii. PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of the gltA and 16S rRNA genes for these 31 isolates yielded similar profiles that were identical to those of B. vinsonii subsp. berkhoffii. Partial sequencing of the gltA and 16S rRNA genes, respectively, indicated 99.5 and 100% homology between the coyote isolate and B. vinsonii subsp. berkhoffii (ATCC 51672). PCR-RFLP analysis of the 16S-23S intergenic spacer region showed the existence of two different strain profiles, as has been reported in dogs. Six (19%) of 31 Bartonella bacteremic coyotes exhibited the strain profile that was identified in the type strain of a canine endocarditis case (B. vinsonii subsp. berkhoffii ATCC 51672). The other 25 bacteremic coyotes were infected with a strain that was similar to the strains isolated from healthy dogs. Based on whole bacterial genome analysis by pulsed-field gel electrophoresis (PFGE) with SmaI restriction endonuclease, there was more diversity in fingerprints for the coyote isolates, which had at least 10 major variants compared to the two variants described for domestic dog isolates from the eastern United States. By PFGE analysis, three Bartonella bacteremic coyotes were infected by a strain identical to the one isolated from three healthy dog carriers. Further studies are necessary to elucidate the mode of transmission of B. vinsonii subsp. berkhoffii, especially to identify potential vectors, and to determine how humans become infected.     

Bartonella vinsonii subsp. arupensis as an agent of blood culture-negative endocarditis in a human

We report the case of a patient hospitalized with endocarditis. The etiological diagnosis of Bartonella was suggested by detection of high titers of antibodies by immunofluorescence and Western blotting. Two different nested PCRs performed on sera identified Bartonella vinsonii subsp. arupensis by sequencing.     

Bartonella vinsonii subsp. berkhoffii and Related Members of the Alpha Subdivision of the Proteobacteria in Dogs with Cardiac Arrhythmias, Endocarditis, or Myocarditis

Cardiac arrhythmias, endocarditis, or myocarditis was identified in 12 dogs, of which 11 were seroreactive to Bartonella vinsonii subspecies berkhoffii antigens. Historical abnormalities were highly variable but frequently included substantial weight loss, syncope, collapse, or sudden death. Fever was an infrequently detected abnormality. Cardiac disease was diagnosed following an illness of short duration in most dogs, but a protracted illness of at least 6 months' duration was reported for four dogs. Valvular endocarditis was diagnosed echocardiographically or histologically in eight dogs, two of which also had moderate to severe multifocal myocarditis. Four dogs lacking definitive evidence of endocarditis were included because of seroreactivity to B. vinsonii antigens and uncharacterized heart murmurs and/or arrhythmias. Alpha proteobacteria were not isolated from the blood by either conventional or lysis centrifugation blood culture techniques. Using PCR amplification and DNA sequencing of a portion of the 16S rRNA gene, B. vinsonii was identified in the blood or heart valves of three dogs. DNA sequence alignment of PCR amplicons derived from blood or tissue samples from seven dogs clustered among members of the alpha subdivision of the Proteobacteria and suggested the possibility of involvement of one or more alpha proteobacteria; however, because of the limited quantity of sequence, the genus could not be identified. Serologic or molecular evidence of coinfection with tick-transmitted pathogens, including Ehrlichia canis, Babesia canis, Babesia gibsonii, or spotted fever group rickettsiae, was obtained for seven dogs. We conclude that B. vinsonii subsp. berkhoffii and closely related species of alpha proteobacteria are an important, previously unrecognized cause of arrhythmias, endocarditis, myocarditis, syncope, and sudden death in dogs.     

Coinfection with Bartonella clarridgeiae and Bartonella henselae and with different Bartonella henselae strains in domestic cats.

Bartonella clarridgeiae and several strains of Bartonella henselae, the agent of cat scratch disease, with variations in the 16S rRNA gene have been found to infect the blood of cats. An epidemiologic study of Bartonella infection in domestic French cats revealed that of 436 cats sampled, 5 cats (1.1%) were coinfected with B. henselae and B. clarridgeiae and 2 cats (0.5%) were coinfected with two strains of B. henselae with variations in the 16S rRNA gene, B. henselae type I and type II. In an indirect immunofluorescence assay, coinfected cats tested positive for both Bartonella species at titers of > or = 128. Identification of the colonies was achieved by preformed enzyme analysis, PCR-restriction fragment length polymorphism analysis of the citrate synthase gene, and 16S rRNA gene sequencing. Colony size differences in mixed culture allowed differentiation of the Bartonella species. The coinfection of cats with two Bartonella species or variants of the same species raises concern about the possibility of dual infection in humans. The development of a polyvalent vaccine targeted against the most pathogenic or invasive strains may be a means of protecting cats and man from infection.     

Prevalence of Bartonella henselae and Bartonella clarridgeiae in stray cats.

The aim of the present work was to determine by blood culture the prevalence of blood infection with Bartonella species in a well-defined, European, urban stray cat population. Therefore, 94 stray cats were trapped from 10 cat colonies. Blood samples of these cats were cultured on both blood agar and liquid medium in order to raise the likelihood of bacterial detection. Fifty blood samples (53%) gave a positive culture result for Bartonella species. Isolate identification was performed by sequencing the first 430 bases of the 16S ribosomal DNA. Three types of sequences were thus obtained. The first type (17 isolates; 34%) was identical to that of B. henselae Houston-1 and the corresponding strains were referred as B. henselae type I. The second sequence type (18 isolates; 36%) was identical to that initially described as "BA-TF," and the corresponding strains were referred to as B. henselae type II. The third sequence type (15 isolates; 30%) was identical to that of the Bartonella clarridgeiae type strain (ATCC 51734). Our study points out the major role of stray cats as a reservoir of Bartonella spp. which can be transmitted to pet cats and, consequently, to humans. The study also highlights the high prevalence of B. clarridgeiae (16%) in the blood of stray cats.     

Intraerythrocytic presence of Bartonella henselae.

Recent reports in the medical literature emphasize the risk of zoonotic disease and the high degree of prevalence of asymptomatic feline infection with Bartonella (Rochalimaea) henselae. While investigating Bartonella bacteremia in cats, we used transmission electron microscopy to demonstrate B. henselae in the erythrocytes of persistently bacteremic cats.     

Seroprevalence of Bartonella henselae in cats in Germany.

Bartonella henselae and B. quintana infections in man are associated with various clinical manifestations including cat-scratch disease, bacillary angiomatosis and bacteraemia. While cats are the natural reservoir for B. henselae, the source of B. quintana is unclear. In this study, the sera of 713 cats from Germany were examined for the presence of antibodies against B. henselae, B. quintana or Afipia felis by an indirect immunofluorescence assay (IFA). Bartonella-specific antibody titres of > or =50 were found in 15.0% of the cats. There was substantial cross-reactivity among the various Bartonella antigens, although single sera showed high titres against B. henselae but not against B. quintana and vice versa. Antibodies against A. felis were not detected in any of these cats. Statistical analysis indicated that there is no correlation between Bartonella infections and the sex, age or breed of the cat or its hunting behavior. There was also no correlation between bartonella and toxoplasma infections in cats. However, whereas 16.8% of cats from northern Germany had B. quintana-specific antibodies, only 8.0% of cats from southern Germany were seropositive for B. quintana. No statistically significant difference was found for B. henselae. IFA-positive and IFA-negative sera were used for immunoblot analysis including B. henselae and B. quintana. Marked reactivity was observed with protein bands at 80, 76, 73, 65, 37, 33 and 15 kDa. The results of this study suggest that B. henselae, and possibly a B. quintana-related pathogen, but not A. felis, are common in cats in Germany, and that there are differences in the geographic distribution of bartonella infections in cats.     

Serological cross-reactions between Bartonella quintana, Bartonella henselae, and Coxiella burnetii.

The clinical manifestations of Q fever and bartonelloses can be confused, especially in cases of infectious endocarditis. Differential diagnosis of the diseases is important because the treatments required for Q fever and bartonelloses are different. Laboratory confirmation of a suspected case of either Q fever or bartonelloses is most commonly made by antibody estimation with an indirect immunofluorescence assay. With an indirect immunofluorescence assay, 258 serum samples from patients with Q fever were tested against Bartonella henselae and Bartonella quintana antigens, and 77 serum samples from patients with infection by Bartonella sp. were tested against Coxiella burnetii antigen. Cross-reactivity was observed: more than 50% of the chronic Q fever patients tested had antibodies which reacted against B. henselae antigen to a significant level. This cross-reaction was confirmed by a cross-adsorption study and protein immunoblotting. However, because the levels of specific antibody titers in cases of Bartonella endocarditis are typically extremely high, low-level cross-reaction between C. burnetii antibodies and B. henselae antigen in cases of Q fever endocarditis should not lead to misdiagnosis, provided serology testing for both agents is performed.     

Infection of human brain vascular pericytes (HBVPs) by Bartonella henselae

Angiogenesis is an important physiological and pathological process. Bartonella is the only genus of bacteria known to induce pathological angiogenesis in the mammalian host. Bartonella-induced angiogenesis leads to the formation of vascular tumors including verruga peruana and bacillary angiomatosis. The mechanism of Bartonella-induced angiogenesis is not completely understood. Pericytes, along with endothelial cells, play an important role in physiological angiogenesis, and their role in tumor angiogenesis has been extensively studied. Abnormal signaling between endothelial cells and pericytes contributes to tumor angiogenesis and metastasis; however, the role of pericytes in Bartonella-induced angiogenesis is not known. In this study, after infecting human brain vascular pericytes (HBVPs) with Bartonella henselae, we found that these bacteria were able to invade HBVPs and that bacterial infection resulted in decreased pericyte proliferation and increased pericyte production of vascular endothelial growth factor (VEGF) when compared to the uninfected control cells. In the context of pathological angiogenesis, reduced pericyte coverage, accompanied by increased VEGF production, may promote endothelial cell proliferation and the formation of new vessels.     

Binding of Bartonella henselae to extracellular molecules: identification of potential adhesins

Bartonella henselae, the etiologic agent of cat scratch disease, bacillary angiomatosis and other clinical syndromes initiates infection through a trauma or wound to the skin suggesting involvement of extracellular matrix molecules. We have demonstrated in this study that B. henselae bound strongly fibronectin, collagen IX and X, but comparatively less laminin and collagen IV. B. henselae bound primarily the N- and C-terminal heparin (Hep-1 and Hep-2, respectively) and the gelatin-binding domains of fibronectin (Fn) but not the cell-binding domain. Binding to the Hep-binding domain was significantly inhibited by Hep suggesting common binding sites on the Fn molecule. Furthermore, glycosaminoglycans-mediated binding of B. henselae to soluble Fn showed that Hep but not dextran sulfate inhibited the bacterium binding to Fn. Unlike Fn, B. henselae bound strongly vitronectin only in the presence of Hep or dextran sulfate. Also, the binding of B. henselae to host cells could be inhibited by anti-B. henselae surface-reactive antibodies, the exogenous Fn or the anti-Fn polyclonal antibodies. Ligand blots, batch affinity purification and MALDI-TOF peptide fingerprinting identified B. henselae Pap31, Omp43 and Omp89 as the three major putative Fn-binding proteins (FnBPs) in B. henselae outer membrane proteins. We hypothesized that B. henselae wound associated infections involved interactions with extracellular matrix molecules. Taken together, the above data suggest that interactions between B. henselae and ECM molecules such as Fn may play an important role in the bacterium adherence to and invasion of host cells.     

Bartonella henselae infection as a cause of fever of unknown origin

Fourteen of 41 patients (34%) with a serological diagnosis of Bartonella henselae infection were found to have prolonged fever or fever of unknown origin, suggesting that generalized systemic B. henselae infection is not rare in immunocompetent healthy individuals.     

Bartonella henselae and Bartonella quintana adherence to and entry into cultured human epithelial cells.

Bartonella henselae expresses pili phenotypically similar to type 4 pili. B. henselae pilus expression undergoes phase variation with multiple passages. Low-passage-number, piliated B. henselae adhered to and invaded HEp-2 cells to a greater extent than did multiply passaged B. henselae with reduced pilus expression. Pili may be a pathogenic determinant for Bartonella species.     

Prevalence of Bartonella henselae and Bartonella clarridgeiae in an Urban Indonesian Cat Population

We studied evidence of Bartonella henselae and Bartonella clarridgeiae infection in 54 cats living in Jakarta, Indonesia. By using an indirect immunofluorescence assay, we found immunoglobulin G antibody to B. henselae in 40 of 74 cats (54%). The blood of 14 feral cats was cultured on rabbit blood agar plates for 28 days. Bartonella-like colonies were identified as B. henselae or B. clarridgeiae by using restriction fragment length polymorphism analysis and direct sequencing of the PCR amplicons. Of the cats sampled in the study, 6 of 14 (43%; all feral) were culture positive for B. henselae; 3 of 14 (21%; 2 feral and 1 pet) culture positive for B. clarridgeiae. This is the first report that documents B. henselae and B. clarridgeiae infections in Indonesian cats.