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Acute rejection remains the main risk factor following intestinal transplantation. New immunosuppressive agents have substantially reduced the incidence of severe acute rejection. The question arises, which is the most powerful immunosuppressive combination with the lowest incidence of side effects? According to International Intestinal Transplant Registry data, anti-IL-2 antibodies are slightly advantageous compared with antilymphocyte preparations with respect to long-term patient survival. However, different antilymphocyte preparations are used in different doses and at different time points. The anti-IL-2 antibodies daclizumab and basiliximab were also used in different protocols. Therefore, final results on efficacy are awaited. The most important difference between IL-2 antibodies and antilymphocyte preparations is the suppression of CD4+ CD25+ T lymphocytes by anti-IL-2 antibodies. Antilymphocyte preparations do not affect CD4+ CD25+ T cells. Because regulatory CD4+ CD25+ T cells are essential for tolerance induction, protocols attempting tolerance may omit anti-IL-2 antibodies in the future.

Patients suffering irreversible loss of intestinal function require total parenteral nutrition (TPN). During long-term TPN, catheter infections are a common problem and intestinal transplantation (ITx) is indicated when patients experience loss of venous access. We report two patients with short bowel syndrome--one before and one after ITx. The patient listed for ITx had several catheter infections with septic temperatures. Staphylococcus aureus, detected in blood cultures, was treated with vancomycin. Packing of the central venous line (CVL) with vancomycin was not successful; the CVL was changed. Search for an infectious focus identified a septic femoral head destruction that was treated by incision and implantation of a hip endoprothesis. Thereafter, the patient was free from infection. The second patient underwent ITx on January 2, 2003, and is free from TPN. ITx was complicated by temporary acute renal failure and heparin-induced thrombocytopenia (HIT) syndrome. After compensation of kidney function, the patient required additional saline solution (1 to 2 L/d) to optimize renal perfusion. A CVL was placed in the external iliac vein (EIV) due to previous loss of venous access. At 2 months after ITx, the CVL was infected and the patient was septic. MR scan revealed only one jugular vein to provide vascular access. Therefore, the CVL was changed from the right to the left EIV. Postoperatively, the patient developed thrombosis of right iliac vein and a wound infection that is probably related to the nearby graft ileostomy. At present, the patient is in good condition with a functioning graft. In conclusion, recurrent CVL infections before ITx might reflect other infectious foci that require intensive diagnostic evaluation. After ITx, CVL infection may cause venous thrombosis. Therefore, a single upper venous access should be preserved for optimal care.

Acute rejection is still the main risk factor following intestinal transplantation. Potent immunosuppression decreases rejection frequency, but may increase immunosuppression-related complications. Isolated small intestinal transplantation was performed in 14 adult patients with short bowel syndromes. Immunosuppression included tacrolimus and rapamycin in combination with steroids for 6 months after ATG or daclizumab induction therapy. In addition to protocol biopsies, cellular immune status and soluble immune parameters were used to guide immunosuppression. CMV and EBV markers were determined on a routine basis. Ten of 14 patients (71%) survived for 1 to 38 months (median 26 months). Eight patients are at home, in good physical condition, completely on enteral nutrition. Among the 5 patients (36%) who developed acute rejection, 2 patients with early postoperative events underwent graft removal and 1 patient died due to multiple organ failure. Two patients developed severe acute rejection episodes at 10 and 24 months following transplantation. Both patients recovered following OKT3 rescue therapy and increased baseline immunosuppression with repeated methylprednisolone and infliximab treatment. Infections included peritonitis (n = 3), pneumonia (n = 3), central line infection (n = 5), urinary tract (n = 2), CMV (n = 2), and EBV (n = 4). Two patients developed anastomotic leaks at the esophageal and coloanal anastomosis. In conclusion, acute rejection episodes can be controlled by potent immunosuppression using tacrolimus in combination with rapamycin. Immunosuppression-associated complications, including infections, were in an acceptable range. However, even late after transplantation, reduction in immunosuppression may lead to severe rejection without major clinical symptoms.

There is some evidence that portal venous drainage may offer immunologic and metabolic advantages in small bowel transplantation. Isolated small bowel transplantation was performed in 14 adult patients. In all cases, the donor pancreas was transplanted into another patient. During the donor procedure, the superior mesenteric artery and vein were separated below the division of the inferior pancreaticoduodenal artery and below the veins of the pancreatic head. An arterial interposition graft was used in all cases. One donor mesenteric artery was reconstructed in 6 patients; two arteries in 5 patients; and three arteries in 3 patients. Proximal arteries of the graft were ligated and the upper part of the jejunum resected. In 10 patients, a direct anastomosis was performed in an end-to side fashion between donor superior mesenteric vein (SMV) and recipient inferior mesenteric vein (IMV). In 2 patients, a branch of the superior mesenteric vein was used and 2 patients required a venous interposition graft to confluence using the donor iliac vein. Patency of the venous anastomosis was documented by magnetic resonance imaging (MRI) angiography after 6 months. No vascular complications have been observed to date. Portal venous drainage is technically feasible in most cases. An anastomosis to the recipient IMV offers the advantage of being direct despite the short donor vein segment. Furthermore, donor and recipient vessels are well matched for size. Using microsurgical techniques, vascular complications may be avoided.