Previous Article | Next Article ![]()
Infect. Immun., 02 1996, 448-451, Vol 64, No. 2
MJ Bancsi, MH Veltrop, RM Bertina and J Thompson
A main feature in the pathogenesis of bacterial endocarditis is the
activation of the coagulation system via the extrinsic pathway, resulting
in the formation of infected endocardial vegetations. Earlier studies gave
indirect evidence that monocytes play an important role in the procoagulant
response during the course of the disease. In this study, we assessed the
role of monocytes more directly. We compared weights and tissue factor
activities (TFA) of endocardial vegetations of normal rabbits infected with
Streptococcus sanguis with those of rabbits which were treated with the
cytostatic drug etoposide (Vepesid; Bristol-Myers Squibb B.V.) to induce a
selective monocytopenia. Furthermore, the importance of the presence of
bacteria was determined through the influence of antibiotic treatment on
TFA, vegetational weight, and infection of the vegetations. The TFA of the
vegetations was measured chromogenically by monitoring the factor
VII-dependent activation of factor X with an amidolytic assay for factor
Xa. We found that the degree of infection and the weight of vegetations of
rabbits treated with the cytostatic drug etoposide did not differ from that
of untreated rabbits. Their TFA, however, was significantly lower than the
TFA of vegetations of rabbits not treated with etoposide. We also found
that, as with the monocytopenic rabbits, the weight of the vegetations was
not reduced in penicillin G-treated rabbits. The degree of infection and
TFA, however, were significantly lower. We conclude that monocytes indeed
are involved in the activation of the coagulation system during the course
of bacterial endocarditis and that the degree of infection is positively
correlated to the TFA of the vegetations.
Copyright © 1996, American Society for Microbiology
Influence of monocytes and antibiotic treatment on tissue factor activity of endocardial vegetations in rabbits infected with Streptococcus sanguis
Department of Infectious Diseases, Leiden University Hospital, The Netherlands.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»