Influence of different protocols of antibiotic prophylaxis on endoluminal bacterial overgrowth and translocation following small-bowel or combined liver-small-bowel transplantation in a large-animal model

Abstract Bacterial translocation from the intestinal tract can cause systemic sepsis and multiple-organ failure in traumatized and immunocompromised patients. Compared to transplantation of other organs, small-bowel transplantation (SBT) is at higher risk of bacterial sepsis. Septic episodes are probably related to the overgrowth of endoluminal microflora and bacterial translocation. Translocation may be secondary to mucosal damage, immunologic impairment, and changes in microflora; in animal models it appeared also to be influenced by dietary factors. Different animal models have been developed, mainly in the mouse or in the rat, to study bacterial translocation, including models of SBT. The participation in a multidisciplinary project on experimental SBT and combined orthotopic liver small-bowel transplantation (OLSBT) offered us the opportunity to assess in a large-animal model like Large White pigs the changes induced in the small-bowel flora and translocation by the graft and the influence of surgical procedure, antibiotic administration, and immunosuppression. Some of our most relevant recent results will be summarized in this paper.