Bartonella Species, an Emerging Cause of Blood-Culture-Negative Endocarditis

Abstract

Since the reclassification of the genus in 1993, the number of species has grown from 1 to 45 currently designated members. Likewise, the association of different species with human disease continues to grow, as does the range of clinical presentations associated with these bacteria. Among these, blood-culture-negative endocarditis stands out as a common, often undiagnosed, clinical presentation of infection with several different species. The limitations of laboratory tests resulting in this underdiagnosis of endocarditis are discussed. The varied clinical picture of infection and a review of clinical aspects of endocarditis caused by are presented. We also summarize the current knowledge of the molecular basis of pathogenesis, focusing on surface adhesins in the two species that most commonly cause endocarditis, and. We discuss evidence that surface adhesins are important factors for autoaggregation and biofilm formation by species. Finally, we propose that biofilm formation is a critical step in the formation of vegetative masses during-mediated endocarditis and represents a potential reservoir for persistence by these bacteria.

Untangling the knots: Co‐infection and diversity of Bartonella from wild gerbils and their associated fleas

“…Fleas are considered key players in rodentassociated Bartonella ecology, not solely as their main vectors, but also as additional reservoirs of Bartonella in the wild (Birtles, 2005; Brinkerhoff, Kabeya, Inoue, Bai, & Maruyama, 2010;Deng et al, 2012;Morick, Krasnov, Khokhlova, Gottlieb, & Harrus, 2013). More than half of the Bartonella species characterized to date, and an extensive list of additionally uncharacterized species and genotypes, have been associated with rodent-flea origin (Bai, Kosoy, Lerdthusnee, Peruski, & Richardson, 2009;Chomel et al, 2009;Harrus et al, 2009;Inoue et al, 2009;Kosoy, Hayman, & Chan, 2012;Okaro, Addisu, Casanas, & Anderson, 2017;Paziewska, Harris, Zwolinska, Bajer, & Sinski, 2011). Although co-infections of rodents and fleas with Bartonella species and genotypes have been reported (Abbot, Aviles, Eller, & Durden, 2007;Brinkerhoff et al, 2010;Chan & Kosoy, 2010), the impact of these events on the diversity and distribution of Bartonella is still underestimated and has been only partially explored.…”

Bartonella quintana, past, present, and future of the scourge of World War I

“… In most of the cases, the diagnoses were post‐mortem . This has not allowed establishing standard antibiotic treatments.…”

“…In addition to B. quintana , at present 34 validated species and an undetermined number of Candidatus species have been described . Of these, at least 19 Bartonella species (15 validated and 4 proposed species) are involved in human infections with Bartonella bacilliformis , Bartonella henselae , and B. quintana being by far the most frequently involved .…”

“…Note that both symptomatic and asymptomatic chronic bacteremic patients are at risk of presenting a posterior life-threatening complication related to B. quintana, acting also as a pathogen reservoir. 6 Often needing surgery for valve replacement. 7 Relevant number of cases in apparently healthy people, including elite sportsman (6).…”

“…6 Often needing surgery for valve replacement. 7 Relevant number of cases in apparently healthy people, including elite sportsman (6). 8 In most of the cases, the diagnoses were post-mortem (5,6).…”