Induction of experimental endocarditis by continuous low-grade bacteremia mimicking spontaneous bacteremia in humans.

Details

Serval ID
serval:BIB_B34D621B640D
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Induction of experimental endocarditis by continuous low-grade bacteremia mimicking spontaneous bacteremia in humans.
Journal
Infection and Immunity
Author(s)
Veloso T.R., Amiguet M., Rousson V., Giddey M., Vouillamoz J., Moreillon P., Entenza J.M.
ISSN
1098-5522 (Electronic)
ISSN-L
0019-9567
Publication state
Published
Issued date
2011
Volume
79
Number
5
Pages
2006-2011
Language
english
Abstract
Transient high-grade bacteremia following invasive procedures carries a risk of infective endocarditis (IE). This is supported by experimental endocarditis. On the other hand, case-control studies showed that IE could be caused by cumulative exposure to low-grade bacteremia occurring during daily activities. However, no experimental demonstration of this latter possibility exists. This study investigated the infectivity in animals of continuous low-grade bacteremia compared to that of brief high-grade bacteremia. Rats with aortic vegetations were inoculated with Streptococcus intermedius, Streptococcus gordonii or Staphylococcus aureus (strains Newman and P8). Animals were challenged with 10(3) to 10(6) CFU. Identical bacterial numbers were given by bolus (1 ml in 1 min) or continuous infusion (0.0017 ml/min over 10 h). Bacteremia was 50 to 1,000 times greater after bolus than during continuous inoculation. Streptococcal bolus inoculation of 10(5) CFU infected 63 to 100% vegetations compared to 30 to 71% infection after continuous infusion (P > 0.05). When increasing the inoculum to 10(6) CFU, bolus inoculation infected 100% vegetations and continuous infusion 70 to 100% (P > 0.05). S. aureus bolus injection of 10(3) CFU infected 46 to 57% valves. This was similar to the 53 to 57% infection rates produced by continuous infusion (P > 0.05). Inoculation of 10(4) CFU of S. aureus infected 80 to 100% vegetations after bolus and 60 to 75% after continuous infusion (P > 0.05). These results show that high-level bacteremia is not required to induce experimental endocarditis and support the hypothesis that cumulative exposure to low-grade bacteremia represents a genuine risk of IE in humans.
Keywords
Animals, Bacteremia/complications, Disease Models, Animal, Endocarditis, Bacterial/blood, Endocarditis, Bacterial/etiology, Female, Humans, Rats, Rats, Wistar, Staphylococcal Infections/blood, Staphylococcal Infections/complications, Streptococcal Infections/blood, Streptococcal Infections/complications
Pubmed
Web of science
Open Access
Yes
Create date
12/10/2011 13:55
Last modification date
20/08/2019 15:21
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