PCR amplification of Bartonella koehlerae from human blood and enrichment blood cultures

Abstract

BackgroundCats appear to be the primary reservoir host for Bartonella koehlerae, an alpha Proteobacteria that is most likely transmitted among cat populations by fleas (Ctenocephalides felis). Bartonella koehlerae has caused endocarditis in a dog and in one human patient from Israel, but other clinically relevant reports involving this bacterium are lacking. Despite publication of numerous, worldwide epidemiological studies designed to determine the prevalence of Bartonella spp. bacteremia in cats, B. koehlerae has never been isolated using conventional blood agar plates. To date, successful isolation of B. koehlerae from cats and from the one human endocarditis patient has consistently required the use of chocolate agar plates.ResultsIn this study, Bartonella koehlerae bacteremia was documented in eight immunocompetent patients by PCR amplification and DNA sequencing, either prior to or after enrichment blood culture using Bartonella alpha Proteobacteria growth medium. Presenting symptoms most often included fatigue, insomnia, joint pain, headache, memory loss, and muscle pain. Four patients were also infected with Bartonella vinsonii subsp. berkhoffii genotype II. After molecular documentation of B. koehlerae infection in these patients, a serological test was developed and serum samples were tested retrospectively. Bartonella koehlerae antibodies were not detected (titers < 1:16) in 30 healthy human control sera, whereas five of eight patient samples had B. koehlerae antibody titers of 1:64 or greater.ConclusionsAlthough biased by a study population consisting of individuals with extensive arthropod and animal exposure, the results of this study suggest that B. koehlerae bacteremia is more common in immunocompetent people than has been previously suspected. Future studies should more thoroughly define modes of transmission and risk factors for acquiring infection with B. koehlerae. In addition, studies are needed to determine if B. koehlerae is a cause or cofactor in the development of arthritis, peripheral neuropathies or tachyarrhythmias in patients.

Intruders below the Radar: Molecular Pathogenesis of Bartonella spp

“…Such systemic infection not only with B. henselae or B. quintana but also with various other zoonotic species can lead to a plethora of symptoms, including extraerythrocytic bacteremia, neuroretinitis, or endocarditis (55,94,143). In addition, various moderate neurological symptoms such as insomnia or memory loss have been reported (53,56,73).…”

Bartonella Species Bacteremia in Two Patients with Epithelioid Hemangioendothelioma

“…Fewer sample sets were available for sequential testing from patient 2, and only B. koehlerae was detected after enrichment culture. Recently, B. koehlerae bacteremia was documented in eight immunocompetent patients with a spectrum of chronic arthritic, cardiovascular, and neurological symptoms and in a girl with peripheral visual deficits, a sensory neuropathy, and hallucinations (5,6,9). Bartonella vinsonii subsp.…”

Hallucinations, Sensory Neuropathy, and Peripheral Visual Deficits in a Young Woman Infected with Bartonella koehlerae

“…B. koehlerae antibodies were not detected in 30 healthy individuals, who were concurrently PCR negative for all components of the BAPGM platform (5). Following suspected needlestick transmission of Bartonella vinsonii subsp.…”

“…Fatigue, insomnia, joint pain, headache, memory loss, and muscle pain were among frequent symptoms in eight patients with B. koehlerae bacteremia, of which four patients reported decreased tactile sensation or numbness and three reported blurred vision (5). B. koehlerae antibodies were not detected in 30 healthy individuals, who were concurrently PCR negative for all components of the BAPGM platform (5).…”

“…berkhoffii genotypes I, II, and III and Bartonella henselae antigens, as previously described (2,5,6,11). At the time of her original testing, our research laboratory did not perform Bartonella koehlerae immunofluorescent-antibody (IFA) testing, and we had not yet developed a B. koehlerae-specific PCR assay.…”