Gastrointestinal decontamination in the compromised host and its clinical significance.

The result documenting the disappearance of obligate anaerobic bacteria as the predominant intestinal organisms with the onset of septicemia from S. marcescens calls for exploration into the clinical significance of anaerobic bacteria in the intestine in relationships between gut flora and host. The finding that no significant difference could be seen between the rates of septicemia under protective isolation and in uncontrolled environments is indicative of the fact that the disease most likely originated as an infection of endogenous nature. In the five cases of leukemia in children with bone marrow transplantation cited in this presentation, not one case of bacterial or fungal infection was recorded. The establishment of endogenous infections surrounding the results presented herein is discussed in terms of the biological phenomena of the interaction between intestinal flora and host, and between the intestinal bacterial flora.