Bacterial Translocation: Cause or Effect of Multiple Organ Failure?

Abstract

Forty-five years ago, Schweinberg et al. [1] documented “transmural migration” of radiolabelled Escherichia coli into the peritoneal cavity of orally inoculated dogs. Clinicians quickly recognized that the insidious passage of bacteria out of an intact intestinal tract could have serious implications for hospitalized patients. Results of experiments designed to clarify the route and mechanisms of transmural migration began to proliferate in the literature, and although many of the mechanisms involved in this process remain obscure and controversial, substantial advances have been made. Transmural migration, now termed bacterial translocation, is generally defined as the passage of bacteria (live and dead) and bacterial products (endotoxin, exotoxins, cell wall fragments) from the intestinal lumen to otherwise sterile extraintestinal sites. Much of the initial skepticism involving the existence of bacterial translocation has dissipated in recent years. In the past decade, results from numerous (literally hundreds) studies in experimental animals have documented that bacterial translocation can be associated with a wide variety of clinical conditions, such as enteric bacterial overgrowth, mesenteric ischemia, hemorrhagic shock, burn wounds and other trauma, surgery, liquid alimentation, bowel stasis, and immunosuppression [reviewed in 2]. Thus, patients at highest risk for increased incidences of bacterial translocation include immunosuppressed patients, postsurgical patients, and trauma patients.