Bacterial translocation and enteral nutrition in humans: an outsider looks in

To assess the literature documenting the existence of bacterial translocation in humans, the effects of enteral nutrition on bacterial translocation in humans, and the hypothesis that enteral nutrition prevents bacterial translocation in humans.

Sources included Medline search, references from review articles, and references from animal and human studies.

The goal was to include all animal and human studies directly addressing questions of bacterial translocation and nutritional status or nutritional support.

An attempt was made to briefly summarize methodology and findings of relevent studies. No general attempt was made to assess quality of individual studies.

Bacterial translocation is a well documented phenomenon in animal models. Starvation and malnutrition of themselves do not induce bacterial translocation, but may facilitate translocation in the presence of other systemic insults. Parenteral nutrition and many forms of enteral nutrition may induce and/or facilitate bacterial translocation. Chow and certain fiber sources seem protective. Moderate direct and several lines of indirect evidence support the existence of bacterial translocation in humans. There is no direct evidence and questionable indirect evidence suggesting that enteral nutrition prevents or modifies bacterial translocation in humans.

The hypothesis relating enteral nutrition and bacterial translocation in critically ill patients remains attractive, but unproven.