摘要:

In the past 15 years, since the first successful long-term survival after small bowel transplantation, there has been a dramatic improvement in outcomes. Small bowel transplantation is now the best option for patients with intestinal failure with life-threatening complications. During this past year a consensus conference agreed on a set of standard indications for small bowel transplantation heralding a major milestone for this field. Other major developments include the demonstration of the need for early referral, the introduction of novel immunotherapy, better control of cytomegaly virus and Epstein-Barr virus, and recognition of the unacceptably high mortality rate for combined liver and small bowel transplantation candidates awaiting transplantation.

ISSN:1087-2418    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Small bowel transplantation is generally reserved for patients with life-threatening complications related to the administration of parenteral nutrition, which includes multiple venous thromboses impeding the placement of feeding catheters and progressive liver disease. Approximately two thirds of recipients are children, who are especially at risk of hepatic complications related to parenteral nutrition. Many patients are in poor condition preoperatively according to the Intestinal Transplant Registry (available at: http://www.intestinaltransplantregistry@uhn.on.ca), with 51% chronically hospitalized and up to 50% dying before donor organs can be provided. The main causes of graft loss are related to the complex surgery undertaken (combined liver and bowel transplants may be complicated by bile leaks or obstruction and small bowel perforation) and the necessity to treat patients with high dose immune suppression because of the highly immunogenic nature of small bowel allografts. Even so, uncontrolled rejection was reason for graft removal in 57% of cases (and death in 9%), but the main cause of death after small bowel transplantation is infection (56.1%). Fatal infectious episodes ensue from common respiratory pathogens such as parainfluenzae, intestinal viruses such as adenovirus and opportunistic pathogens such as vancomycin resistant enterococcus, pneumocystic carinii and Epstein-Barr virus. Lymphoma caused by Epstein-Barr virus is a particular risk in pediatric recipients who are usually naive to the virus, and up to 50% of infants can become infected by the graft at the time of transplant or shortly after being discharged. Treatment toxicity also contributes to mortality after transplantation: tacrolimus, mycophenolate, and sirolimus can all produce profound bone marrow suppression; nephrotoxicity also complicates the use of tacrolimus, and impaired wound healing is associated with steroids and sirolimus. New strategies are being developed to reduce the mortality after small bowel transplantation, including the use of interleukin-2 inhibitors, early detection and treatment of viruses such as Epstein-Barr virus and adenovirus, monitoring the immune responsiveness of patients, and technical improvements to the transplant operation.

ISSN:1087-2418    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Traditional outcomes for transplant recipients include patient and graft survival. Currently, patient survival is between 60 and 75% at 1 year, which is dramatically improved since the introduction of intestinal transplantation just over 1 decade ago. Early graft survival is best for isolated small bowel, but this survival advantage is lost over time. Functional outcomes are also examined in this section. Most patients with intact grafts are able to maintain all of their caloric needs through absorption of nutrients from the intestinal allograft. Growth velocity may improve after intestinal transplantation; however, catch-up growth is uncommon. Quality of life for adult recipients appears to be similar to patients on total parenteral nutrition and for pediatric recipients similar to normal school children. Intestinal transplantation has become a standard therapy for patients with intestinal failure with life-threatening complications of total parenteral nutrition administration.

ISSN:1087-2418    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Because of unique immunologic and anatomic features, the results of intestinal transplantation remain significantly inferior to those associated with the transplantation of many other organs. Achieving improvements in allograft survival and function will require a more detailed understanding of the mechanisms responsible for allograft damage and the design, based on this understanding, of new strategies to better control the tissue injury resulting from organ preservation/ischemia and the recipient immune response. In this article, we review the different models that have been used to study intestinal transplantation, highlight important and/or recent results obtained using these various experimental models, and describe experimental approaches aimed at developing alternatives to allogeneic intestinal transplantation.

ISSN:1087-2418    

出版商:OVID    

年代:2003

数据来源: OVID