Luminal bacterial overgrowth and intestinal translocation in pigs given either cyclosporin A or 15-deoxyspergualin after small bowel transplantation

To examine the effects of two immunosuppressant regimens on composition of the bowel flora and rate of translocation after transplantation of the small bowel in pigs. DESIGN: Randomised controlled study. SETTING: University hospital, Italy. MATERIAL: 35 female Large White pigs. INTERVENTIONS: 9 Animals were not operated on (normal controls). 19 Animals underwent total orthotopic small bowel allotransplantation and were then randomised to receive: group A (n = 8) cyclosporin A 25 mg/kg subcutaneously and cephazolin 2 g intramuscularly daily; group B (n = 6) 15-deoxyspergualin (15-dos) 3 mg/kg for 7 days then 1.5 mg/kg, cephazolin 2 g intramuscularly daily for 4 days then selective intestinal decontamination with colistin 1.5 million U, tobramycin 100 mg, vancomycin 1 g, and nystatin 500,000 U daily; and group C (n = 5) cephazolin 2 g intramuscularly daily for 8 days. A further group (D, n = 7) underwent orthotopic autotransplantation and received the same antibiotic and selective decontamination regimens as group B. Animals in group C were killed on day 8, and the rest on day 29. MAIN OUTCOME MEASURES: Signs of rejection, graft versus host disease, luminal overgrowth, and evidence of translocation to mesenteric lymph nodes. RESULTS: All animals in group C, and 2 in group B, showed signs of acute rejection. There was a significant overgrowth of both aerobic and anaerobic bacteria in all 3 groups after allotransplantation compared with normal controls. Bacterial translocation was similar in autografted and allotransplanted animals. Mesenteric lymph nodes were colonised in 4/9 controls, 7/8 in group A, 4/4 in group B, 5/5 in group C, and 7/7 in group D. CONCLUSION: Neither cyclosporin A nor 15-dos prevented luminal overgrowth or bacterial translocation to mesenteric nodes up to one month after operation. The rate of translocation was similar in autotransplantation and allotransplantation, suggesting that non-immunological factors (for example, denervation and interruption of lymphatics) may have a role in these alterations.