Prevalence of Bartonella henselae bacteremia, the causative agent of cat scratch disease, in an australian cat population

Improved Culture from Lymph Nodes of Patients with Cat Scratch Disease and Genotypic Characterization of Bartonella henselae Isolates in Australia

“…However, very few cases have been reported in Australia, and Branley et al (10) and Ng and Yates (34), who have observed a B. henselae bacteremia rate in Australian cats similar to that in other geographic areas, have hypothesized that CSD was underdiagnosed. In addition, no report of the isolation of B. henselae from patients with CSD is available from Australia.…”

“…In our study, we obtained 17 B. henselae isolates from patients' specimens, which represents the largest collection of strains from patients with CSD to date. This demonstrates the efficiency of our culture protocol, which was adapted from the blood culture protocol for cats (10). In particular, hemin was added to blood agar, and the period of incubation in a humid atmosphere was prolonged.…”

“…Among the blood culture techniques tested, those that include erythrocyte lysis with saponin or by freezing prior to plating on bloodenriched and/or hemin-enriched agar and prolonged incubation have proved particularly efficient (12,38). When these techniques are applied to epidemiological studies with cats, a B. henselae prevalence of between 10 and 40% was found in the populations in America, Asia, Australia, and Europe tested (6,10,14,16,26,28,30,34,37). In contrast, B. henselae is infrequently grown from the lymph nodes of humans.…”

“…Another major point is the length of incubation. B. henselae is a slow grower when cultivated from clinical material (24), and several investigators (10,18) have highlighted the necessity of prolonged incubation. However, prolonged incubation requires a moist atmosphere to avoid desiccation of agar plates, and the agar plates are at risk of contamination by yeasts.…”

Phase variation in Bartonella henselae

“…Bartonella henselae is an ubiquitous flea-borne feline pathogen with a seroprevalence of 3-6 % in blood donors in the USA and Australia (Branley et al, 1996;Chomel et al, 1995;Foley et al, 1998;Jackson et al, 1993;Koehler et al, 1994), which is capable of infecting other animals and causing serious illness in humans (Anderson & Neuman, 1997). Key virulence attributes probably include the ability to express a rigid polar (putative type IV) pilin (Batterman et al, 1995) and invade epithelial cells (Batterman et al, 1995;Dehio et al, 1997), to stimulate angiogenesis in endothelial cells (Burgess & Anderson, 1998;Kempf et al, 2001), and to attenuate phagocyte attack (Fumarola et al, 1994).…”