Isolation of Bartonella washoensis from a dog with mitral valve endocarditis

Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, California 95616, USA.
Journal of Clinical Microbiology (Impact Factor: 4.23). 12/2003; 41(11):5327-32. DOI: 10.1128/JCM.41.11.5327-5332.2003
Source: PubMed

ABSTRACT We report the first documented case of Bartonella washoensis bacteremia in a dog with mitral valve endocarditis. B. washoensis was isolated in 1995 from a human patient with cardiac disease. The main reservoir species appears to be ground squirrels (Spermophilus beecheyi) in the western United States. Based on echocardiographic findings, a diagnosis of infective vegetative valvular mitral endocarditis was made in a spayed 12-year-old female Doberman pinscher. A year prior to presentation, the referring veterinarian had detected a heart murmur, which led to progressive dyspnea and a diagnosis of congestive heart failure the week before examination. One month after initial presentation, symptoms worsened. An emergency therapy for congestive heart failure was unsuccessfully implemented, and necropsy evaluation of the dog was not permitted. Indirect immunofluorescence tests showed that the dog was strongly seropositive (titer of 1:4,096) for several Bartonella antigens (B. vinsonii subsp. berkhoffii, B. clarridgeiae, and B. henselae), highly suggestive of Bartonella endocarditis. Standard aerobic and aerobic-anaerobic cultures were negative. However, a specific blood culture for Bartonella isolation grew a fastidious, gram-negative organism 7 days after being plated. Phenotypic and genotypic characterizations of the isolate, including partial sequencing of the citrate synthase (gltA), groEL, and 16S rRNA genes, indicated that this organism was identical to B. washoensis. The dog was seronegative for all tick-borne pathogens tested (Anaplasma phagocytophilum, Ehrlichia canis, and Rickettsia rickettsii), but the sample was highly positive for B. washoensis (titer of 1:8,192) and, according to indirect immunofluorescent-antibody assay, weakly positive for phase II Coxiella burnetii infection.

  • [Show abstract] [Hide abstract]
    ABSTRACT: In recent years, an increasing number of Bartonella species have been identified as zoonotic pathogens, transmitted by animal bites, scratches, arthropods and even by needle sticks. Considering the diversity of newly discovered Bartonella species and subspecies and the large number and ecologically diverse animal reservoir hosts and the evolving spectrum of arthropod vectors that can transmit these bacteria among animals and humans, the clinical and diagnostic challenges posed by Bartonella transmission in nature are presumably much more complex than is currently appreciated by diagnosticians, vector biologists, ecologists, physicians, or veterinarians. Historically the term "bartonellosis" was attributed to infections with Bartonella bacilliformis, transmitted by sandflies in the Peruvian Andes. Currently, however, bartonellosis now includes infections caused by any Bartonella sp. anywhere in the world. Potentially, because Bartonella spp. can infect erythrocytes, endothelial cells, pericytes, CD34(+) progenitor cells, and various macrophage-type cells, including microglial cells, dendritic cells, and circulating monocytes in vitro, the clinical and pathological manifestations of bartonellosis appear to be very diverse in both sick animals and human patients. Because 75% of emerging infectious diseases are zoonoses, many of which are vector-transmitted by an arthropod, a One Health approach to bartonellosis and other zoonotic infections is needed to properly address animal health, public health, and environmental factors that influence the distribution and transmission of these bacteria. The One Health concept encourages a spirit of cooperation among animal, environmental, and human health professionals and promotes developing integrated solutions for complex problems that impact the health of animals, humans, and the planet. Importantly, substantial research is needed to define the medical importance of this genus as a cause of animal and human illnesses.
    ILAR journal / National Research Council, Institute of Laboratory Animal Resources 06/2014; 55(1):46-58. DOI:10.1093/ilar/ilu015 · 1.05 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Dogs can be infected by a wide variety of Bartonella species. However, limited data is available on experimental infection of dogs with Bartonella strains isolated from domestic animals or wildlife. We report the inoculation of six dogs with Bartonella henselae (feline strain 94022, 16S rRNA type II) in three sets of two dogs, each receiving a different inoculum dose), four dogs inoculated with B. vinsonii subsp. berkhoffii type I (ATCC strain, one mongrel dog) or type II (coyote strain, two beagles and one mongrel) and B. rochalimae (coyote strain, two beagles). None of the dogs inoculated with B. henselae became bacteremic, as detected by classical blood culture. However, several dogs developed severe necrotic lesions at the inoculation site and all six dogs seroconverted within one to two weeks. All dogs inoculated with the B. v. berkhoffii and B. rochalimae strains became bacteremic at levels comparable to previous experimental infections with either a dog isolate or a human isolate. Our data support that dogs are likely accidental hosts for B. henselae, just like humans, and are efficient reservoirs for both B. v. berkhoffii and B. rochalimae.
    Veterinary Microbiology 11/2013; DOI:10.1016/j.vetmic.2013.11.009 · 2.73 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Since 2002, an increased number of northern sea otters (Enhydra lutris kenyoni) from southcentral Alaska have been reported to be dying due to endocarditis and/or septicemia with infection by Streptococcus infantarius subsp. coli. Bartonella spp. DNA was also detected in northern sea otters as part of mortality investigations during this unusual mortality event (UME) in Kachemak Bay, Alaska. To evaluate the extent of exposure to Bartonella spp. in sea otters, sera collected from necropsied and live-captured northern sea otters, as well as necropsied southern sea otters (Enhydra lutris nereis) unaffected by the UME, were analyzed using an immunofluorescent antibody assay. Antibodies against Bartonella spp. were detected in sera from 50% of necropsied and 34% of presumed healthy, live-captured northern sea otters and in 16% of necropsied southern sea otters. The majority of sea otters with reactive sera were seropositive for B. washoensis, with antibody titers ranging from 1:64 to 1:256. Bartonella spp. antibodies were especially common in adult northern sea otters, both free-living (49%) and necropsied (62%). Adult stranded northern sea otters that died from infectious causes, such as opportunistic bacterial infections, were 27 times more likely to be Bartonella seropositive than adult stranded northern sea otters that died from noninfectious causes (p<0.001; 95% confidence interval 2.62-269.4). Because Bartonella spp. antibodies were detected in necropsied northern sea otters from southcentral (44%) and southwestern (86%) stocks of Alaska, as well as in necropsied southern sea otters (16%) in southcentral California, we concluded that Bartonella spp. exposure is widely distributed among sea otter populations in the Eastern Pacific, providing context for investigating future disease outbreaks and monitoring of Bartonella infections for sea otter management and conservation.
    Vector Borne and Zoonotic Diseases 12/2014; 14(12):831-7. DOI:10.1089/vbz.2014.1612 · 2.53 Impact Factor