Alterations of Responses to Bacterial Endotoxin by Bacteroides Fragilis in Vivo and in Vitro

Abstract

Gram negative obligately anaerobic bacteria constitute a major part of the normal indigenous bacterial flora of humans, however, they also have to be considered to be important opportunistic pathogens, e.g., infections with Bacteroidaceae may arise, when the function of the mucous membranes as anato­mic barrier for microorganisms is compromised and bacteria are introduced into otherwise sterile tissues. In such instances, the resulting infection is often of polymicrobial etiology and Bacteroidaceae are found especially in association with Enterobacteriaceae. It is clinical experience that these mixed aerobic/anaerobic infections create significant therapeutical problems even if the individual causative microorganisms display a high in-vitro­susceptibility to antimicrobial agents employed. Therefore, efforts were made to study the interaction of aerobes and anaerobes in mixed infections with a number of different animal models.