Bacterial translocation after non-lethal hemorrhage in the rat.

Translocation of enteric bacteria has been suggested to compromise patients in severe catabolic stress. Mechanisms for this route of infection are not known. In this study, rats were subjected to hemorrhage without reinfusion during 60 min, total blood loss was 3.28 +/- 0.14 ml/100 g BW. Control groups consisted of sham-operated animals without bleeding, and rats not operated at all. The mean number of viable bacteria found in mesenteric lymph nodes (MLN) of bled animals was 168 +/- 45 colony forming units (c.f.u./MLN), significantly higher compared to sham operated (5 +/- 3 c.f.u./MLN) and not operated (0 +/- 0 c.f.u./MLN) controls (P < 0.01). Cultures from MLN were positive in 7/9 rats after bleeding, in 3/9 of sham operated, and in 0/6 of non-instrumented control animals. No positive blood cultures were isolated. Escherichia coli was the dominant species found in MLN. A biochemical fingerprinting method (the PhP system) was used to identify translocating strains of E. coli among strains found in cecum. The method was also used to compare translocating strains between different animals. Our findings reveal that bacteria translocate to MLN after hemorrhage. Some phenotypes of E. coli strains translocate more frequently than others, suggesting that they have properties facilitating translocation.