 |
 |

Lethal Microbial Synergism in Intra-abdominal InfectionsEscherichia coli and Bacteroides fragilis
Ori D. Rotstein, MD;
Timothy L. Pruett, MD;
Richard L. Simmons, MD
Arch Surg. 1985;120(2):146-151.
Abstract
 |  |
The ability of Bacteroides fragilis and Escherichia coli to produce synergistic mortality when mixed into intraperitoneal (IP) fibrin clots was tested in rats. The addition of B fragilis (2x109 colony-forming units/clot) to E coli (2 x108 colonyforming units/clot) in the clot significantly enhanced both early and late mortality rates when compared to either E coli or B fragilis alone. Multiple washings of B fragilis prior to mixing with E coli in the clot delayed the enhancement of lethality from 24 to 48 hours. By seven days, washed B fragilis was as synergistic with E coli as unwashed B fragilis plus E coli. Furthermore, unwashed killed B fragilis was as synergistic when mixed with E coli in the fibrin clot as unwashed living B fragilis. However, washed dead B fragilis plus E coli produced no greater mortality than E coli alone. The lethality of an IP clot containing E coli was significantly increased when B fragilis was mixed with it in the same clot, injected free IP, and or implanted into a separate IP clot. intraperitoneal E coli—fibrin clot lethality was not increased by subcutaneous B fragilis and was only slightly enhanced by intravenous B fragilis inoculation. The strain of B fragilis used in these studies did not produce fibrinolysins at any concentration. The data support the idea that synergistic mortality between E coli and B fragilis in this model is caused by a heat-stable surface factor produced by B fragilis, which acts to increase the lethal effects of E coli.
(Arch Surg 1985;120:146-151)
Author Affiliations
From the Division of Surgical Infectious Diseases, Department of Surgery, University of Minnesota, Minneapolis.
Footnotes
Accepted for publication Aug 14, 1984.
Read before the Fourth Annual Meeting of the Surgical Infection Society, Montreal, April 30, 1984.
Reprint requests to Box 185, Mayo Building, University of Minnesota, 420 Delaware St SE, Minneapolis, MN 55455 (Dr Rotstein).
CiteULike Connotea Del.icio.us Digg Reddit Technorati Twitter
What's this?
THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES
Succinic Acid Production by Bacteroides fragilis: A Potential Bacterial Virulence Factor
Rotstein et al.
Arch Surg 1987;122:93-98.
ABSTRACT
A Bacteroides By-product Inhibits Human Polymorphonuclear Leukocyte Function
Rotstein et al.
Arch Surg 1986;121:82-88.
ABSTRACT
Intestinal Bacteria Translocate Into Experimental Intra-abdominal Abscesses
Wells et al.
Arch Surg 1986;121:102-107.
ABSTRACT
|