Bartonella infections in cats and dogs

With the discovery of HIV, the resurgence of infectious disease research coupled with new technologies in molecular biology enabled great strides in the detection and identification of infectious agents. Genotypic analysis of organisms associated with bacillary angiomatosis, culture negative endocarditis, bacteremia, and cat scratch disease resulted in the description of several new species in the Genus Bartonella. and helped optimize growth conditions to enhance isolation. A seroepidemiologic study revealed that large numbers of CSD patients were seroreactive to B. henselae . We performed serology and blood culture on CSD associated, retroviral infected, and healthy cats to determine prevalence of Bartonella infection in cats. Seroreactivity was detected in 18/22 CSD-associated, 10/51 retroviral infected, and 11/25 healthy cats. Positive blood cultures were obtained from 20/22 CSD associated, 10/51 retroviral infected, and 7/25 healthy cats. Repeated serology and blood culture attempts in CSD associated cats during a 24 month period established a database to support the existence of prolonged bacteremia in many of these cats. During follow-up of chronically bacteremic cats, we demonstrated the intraerythrocytic presence of bartonella in feline erythrocytes by electron microscopy. Until then, it was assumed that only one Bartonella species, B. henselae, was infecting cats and responsible for CSD. During our study of CSD-associated cats, a veterinarian adopted a stray kitten, was bitten, and developed clinical signs of CSD. A Bartonella isolate was recovered from the kitten and the veterinarian displayed seroreactivity against this isolate but not the Bartonella strain typically associated with CSD. In addition, by electron microscopy, this strain had lophotrichous flagella which are not expressed by B. henselae. Further phenotypic and genotypic testing confirmed that this was a previously unrecognized Bartonella species. Retrospective analysis of other Bartonella isolates from cats indicated that 10% were this novel species, B. clarridgeiae. We also isolated and characterized another unique Bartonella species, from a dog with endocarditis. Characterization of this strain and another from a subclinically infected blood donor dog resulted in the description of B. vinsonii berkhoffii, a species that infects dogs but has not been found in other domestic animals. Abstract shortened by UMI.)...