Bacterial translocation in clinical intestinal transplantation

Background. Bacterial translocation (BT) has been suggested to be responsib le for the high incidence of infections occurring after small bowel transpl antation (SBTx). Bacterial overgrowth, alteration of the mucosal barrier fu nction as a consequence of preservation injury or acute rejection (AR), and potent immunosuppression are all associated with BT, The aim of this study was to evaluate and quantify the correlation of BT with these events. Methods. Fifty pediatric SBTx recipients on tacrolimus and prednisone immun osuppression were analyzed. Blood, stool, and liver biopsies and peritoneal fluid were cultured (circa 4000 total specimens) when infection was clinic ally suspected or as part of followup, BT episodes were considered when mic roorganisms were found simultaneously in blood or liver biopsy and stool. Results. BT (average of 2.0 episodes/patient) was evident in 44% of patient s and was most frequently caused by Enterococcus, Staphylococcus, Enterobac ter, and Klebsiella, The presence of a colon allograft was associated with a higher rate of BT (75% vs. 33.3%), Furthermore, the transplantation proce dure (colon vs. no colon) affected the rate of BT: SBTx=40% vs. 25%, combin ed Liver and SBTx=100% vs. 30%, multivisceral transplantation=25% vs. 50%. AR was associated with 39% of BT episodes. BT followed AR in 9.6% of the ca ses, In 5.2% of the cases, positive blood cultures without stool confirmati on of the bacteria were seen. Prolonged cold ischemia time (CIT) affected B T rate significantly (CIT >9 hr 76% vs. CIT <9 hr 20.8%). Conclusions. This study shows that 1) a substantial percentage of, but not ah, BT is associated with AR, 2) the presence of a colon allograft increase s the risk for BT, and 3) a long CIT is associated with a high incidence of BT after SBTx.