Combined living donor liver/small bowel transplantation

Combined Organ Transplantation in Patients with Advanced Liver Disease

Transplantation of the liver in combination with other organs is an increasingly performed procedure. Over the years, continuous improvement in survival could be realized through careful patient selection and refined organ preservation techniques, in spite of the challenges posed by aging recipients and donors, as well as the increased use of steatotic liver grafts. Herein, we revisit the epidemiology, allocation policies in different transplant zones, indications, and outcomes with regard to simultaneous organ transplants involving the liver, that is combined heart-liver, liver-lung, liver-kidney, and multivisceral transplantation. We address challenges surrounding combined organ transplantation such as equity, utility, and logistics of dual organ implantation, but also advantages that come along with combined transplantation, thereby focusing on molecular mechanisms underlying immunoprotection provided by the liver to the other allografts. In addition, the current standing and knowledge of machine perfusion in combined organ transplantation, mostly based on center experience, will be reviewed. Notwithstanding all the technical advances, shortage of organs, and the lack of universal eligibility criteria for certain multi-organ combinations are hurdles that need to be tackled in the future.

Outcome After Intestinal Transplantation From Living Versus Deceased Donors: A Propensity-matched Cohort Analysis of the International Intestinal Transplant Registry

OBJECTIVE

To describe the worldwide experience with living donation (LD) in intestinal transplantation (ITx) and compare short-term and long-term outcomes to a propensity-matched cohort of deceased donors.

BACKGROUND

ITx is a rare life-saving procedure for patients with complicated intestinal failure (IF). Living donation (LD)-ITx has been performed with success, but no direct comparison with deceased donation (DD) has been performed. The Intestinal Transplant Registry (ITR) was created in 1985 by the Intestinal Transplant Association to capture the worldwide activity and promote center's collaborations.

METHODS

Based on the ITR, 4156 ITx were performed between January 1987 and April 2019, of which 76 (1.8%) were LD, including 5 combined liver-ITx, 7 ITx-colon, and 64 isolated ITx. They were matched with 186 DD-ITx for recipient age/sex, weight, region, IF-cause, retransplant, pretransplant status, ABO compatibility, immunosuppression, and transplant date. Primary endpoints were acute rejection and 1-/5-year patient/graft survival.

RESULTS

Most LDs were performed in North America (61%), followed by Asia (29%). The mean recipient age was: 22 years; body mass index: 19kg/m²; and female/male ratio: 1/1.4. Volvulus (N=17) and ischemia (N=17) were the most frequent IF-causes. Fifty-two percent of patients were at home at the time of transplant. One-/5-year patient survival for LD and DD was 74.2/49.8% versus 80.3/48.1%, respectively ( P =0.826). One-/5-year graft survival was 60.3/40.6% versus 69.2/36.1%, respectively ( P =0.956). Acute rejection was diagnosed in 47% of LD versus 51% of DD ( P =0.723).

CONCLUSION

Worldwide, LD-ITx has been rarely performed. This retrospective matched ITR analysis revealed no difference in rejection and in patient/graft survival between LD and DD-ITx.

Kidney After Intestinal Transplantation Using Two Different Living Donors: A First Case Report

We describe a unique case of a 53-year-old woman who underwent a nonrelated living donor kidney transplant 9 years after a previous small bowel transplant from her sister. The patient had suffered from short bowel syndrome secondary to volvulus after undergoing bariatric surgery for morbid obesity. Her entire small bowel had to be resected emergently, but she also developed acute kidney failure at the time. This initial kidney injury associated with long-term exposure to calcineurin-inhibitor medication eventually led to end-stage renal disease. A successful kidney transplant from a different, nonrelated adult donor was performed. Of note, the unrelated kidney donor matched exactly the 2 HLA-A and HLA-B antigens that the recipient had not matched with her sister. We discuss the unique HLA configuration between the patient and her 2 living donors, the absence of posttransplant rejection and posttransplant immunosuppressive therapy. To our knowledge this is the first published report of a successful kidney after a previous bowel transplant using (2 different) living donors.

Landscape of Living Multiorgan Donation in the United States: A Registry-Based Cohort Study

BACKGROUND

The donation of multiple allografts from a single living donor is a rare practice, and the patient characteristics and outcomes associated with these procedures are not well described.

METHODS

Using the Scientific Registry of Transplant Recipients, we identified 101 living multiorgan donors and their 133 recipients.

RESULTS

The 49 sequential (donations during separate procedures) multiorgan donors provided grafts to 81 recipients: 21 kidney-then-liver, 15 liver-then-kidney, 5 lung-then-kidney, 3 liver-then-intestine, 3 kidney-then-pancreas, 1 lung-then-liver, and 1 pancreas-then-kidney. Of these donors, 38% donated 2 grafts to the same recipient and 15% donated 2 grafts as non-directed donors. Compared to recipients from first-time, single organ living donors, recipients from second-time living donors had similar graft and patient survival. The 52 simultaneous (multiple donations during one procedure) multiorgan donors provided 2 grafts to 1 recipient each: 48 kidney-pancreas and 4 liver-intestine. Donors had median of 13.4 years (interquartile range, 8.3-18.5 years) of follow-up. There was one reported death of a sequential donor (2.5 years after second donation). Few postdonation complications were reported over a median of 116 days (interquartile range, 0-295 days) of follow-up; however, routine living donor follow-up data were sparse. Recipients of kidneys from second-time living donors had similar graft (P = 0.2) and patient survival (P = 0.4) when compared with recipients from first-time living donors. Similarly, recipients of livers from second-time living donors had similar graft survival (P = 0.9) and patient survival (P = 0.7) when compared with recipients from first-time living donors.

CONCLUSIONS

Careful documentation of outcomes is needed to ensure ethical practices in selection, informed consent, and postdonation care of this unique donor community.

Solid-organ Transplants From Living Donors: Cumulative United States Experience on 140,156 Living Donor Transplants Over 28 Years

BACKGROUND

Transplantation of organs from living donors helps to decrease the organ shortage and shortens waiting times. Living donor (LD) transplantation is also generally associated with better outcomes. Unfortunately, there has been no comprehensive analysis and comparison of all types of solid-organ transplantation from living donors since the inception of the United Network for Organ Sharing (UNOS).

METHODS

Using the UNOS/Organ Procurement and Transplantation Network (OPTN) database, all LD transplants from October 1, 1987, to December 31, 2015, were studied with univariate and multivariate analyses.

RESULTS

A total of 140,090 organs were transplanted from LDs, accounting for 21% of all transplants in the United States. Over 95% were kidney; 4% were liver; and <1% intestine, lung, and pancreas LDs. Only LD kidney transplant patient and graft survival rates were significantly higher compared deceased donor transplants over the period of analysis. The best long-term LD transplant results were achieved in pediatric liver recipients. Significantly more women than men donated organs and significantly more men than women received solid-organ transplants. A regional disparity was observed for LD kidney as well as for LD liver transplants. Despite improvements in outcomes and increased use of nonbiologic donors, the number of LD transplants in the United States has declined. This decline was greater in children than adults and was noted for all types of organ transplants.

CONCLUSION

Further efforts are needed to educate the public, health professionals, and transplant candidates on the advantages of living vs deceased donor organ transplantation. Compared with other countries, LD transplantation has yet to reach its full potential in the United States.

Intestinal transplantation: an unexpected journey. Robert E. Gross Lecture

The development of pediatric intestine transplantation has required continuous refinements in the management of intestinal failure, surgical technique, and perioperative care. The development of better immunosuppressive management (cyclosporine in 1978 and tacrolimus in 1989) and enhancements in our understanding of the relationship between recipient and host immune systems have resulted in better long-term survival. Paralleling this, advancements in the organ procurement techniques and organ preservation solutions have made possible the procurement and transplantation of various types of intestine containing grafts tailored to the needs of the various indications for which intestine transplantation is being performed. With improved outcomes, the indications for intestine transplantation have been better defined in the context of risk benefit for the most important complications of TPN, which include liver disease, life threatening infection, and loss of central venous access. The first survivors of transplantation would also go on to demonstrate the interaction (host-versus-graft and graft-versus-host) between recipient and donor immunocytes (brought with the allograft), which under the cover of immunosuppression allows varying degrees of graft acceptance. The struggle to achieve better transplantation survival outcomes came about with the development of improved strategies to better manage intestinal failure. This has been accomplished largely through the establishment of centers that incorporate a multidisciplinary team approach to medical and surgical care. Intestine transplantation represents a lifesaving therapy for many patients with intestinal failure who have significant complications of their disease. It is hoped that with the minimization of immunosuppression strategies currently used, the long-term survival of these intestine organ transplant recipients will continue improving, together with their rehabilitation and quality-of-life.

Intestinal Transplantation from Living Donors

Intestinal transplantation (ITx) represents the physiologic alternative to total parenteral nutrition (TPN) for patients suffering from life-threatening complications of irreversible intestinal failure. The number of transplants performed worldwide has been increasing for several years until recently. ITx has recently become a valid therapeutic option with a graft survival rate between 80 % and 90 % at 1 year, in experienced centers. These results have been achieved due to a combination of several factors: better understanding of the pathophysiology of intestinal graft, improved immunosuppression techniques, more efficient strategies for the monitoring of the bowel graft, as well as control of infectious complications and posttransplant lymphoproliferative disease (PTLD). In fact, this procedure is associated with a relatively high rate of complications, such as infections, acute rejection, graft versus host disease (GVHD), and PTLD, if compared to the transplantation of other organs. These complications may be, at least in part, the consequence of the peculiarity of this graft, which contains gut-associated lymphoid tissue and potentially pathogenic enteric flora. Furthermore, in these patients, the existing disease and the relative malnutrition could predispose them to infectious complications. Additionally, other factors associated with the procedure, such as laparotomy, preservation injury, abnormal motility, and lymphatic disruption, could all be implicated in the development of complications.

Where are we at with short bowel syndrome and small bowel transplant

Intestinal failure can be defined as the critical reduction of functional gut mass below the minimal amount necessary for adequate digestion and absorption to satisfy body nutrient and fluid requirements in adults or children. Short bowel syndrome (SBS) is characterized by a state of malabsorption following extensive resection of the small bowel. SBS may occur after resection of more than 50% and is certain after resection of more than 70% of the small intestine, or if less than 100 cm of small bowel is left. Several treatment modalities other than total parenteral nutrition, including hormones (recombinant human growth hormone, glucagon-like peptide-2) and tailoring surgeries (Bianchi procedure, serial transverse enteroplasty), had been proposed, however these were either experimental or inefficient. Small bowel transplant is a rather new approach for SBS. The once feared field of solid organ transplantation is nowadays becoming more and more popular, even in developing countries. This is partially secondary to the developments in immunosuppressive strategy. In this regard, alemtuzumab deserves special attention. There are more complex surgeries, such as multivisceral transplantation, for multi-organ involvement including small bowel. This latter technique is relatively new when compared to small bowel transplant, and is performed in certain centers worldwide. In this review, an attempt is made to give an insight into small bowel syndrome, small bowel transplantation, and related issues.

Current status of living donor small bowel transplantation

PURPOSE OF REVIEW

To analyze the current status of living donor intestinal transplantation (LDIT) as a treatment option for intestinal failure.

RECENT FINDINGS

Long-term outcomes from LDIT and combined living donor intestinal/liver transplantation (CLDILT) are comparable with those from transplantation using deceased donors. In certain life-threatening situations, especially in pediatric patients, this strategy may offer potential advantages.

SUMMARY

According United Network for Organ Sharing (UNOS) data children with intestinal failure affected by liver disease secondary to parenteral nutrition have the highest mortality on a waiting list compared with all candidates for solid organ transplantation. Elective nature of CLDILT offers multiple advantages for this patient population. LDIT also could be life-saving option for patients with intestinal failure who run out of venous access. Optimal timing, short ischemia time and good human leukocyte antigen (HLA) matching may contribute to lower postoperative complications. Current literature suggests that living intestinal donors experience very low morbidity and high level of satisfaction.

Intestinal transplantation: current outcomes and opportunities

PURPOSE OF REVIEW

This review highlights current outcomes in intestinal transplantation and summarizes advances that have recently occurred in five interrelated areas: progress in intestinal rehabilitation, immunologic and technical modifications, awareness of opportunities for improved allograft monitoring, and better assessment of long-term complications and morbidities.

RECENT FINDINGS

Improved long-term management of patients with intestinal failure as well as improved outcomes with intestine transplant are changing the previously established paradigms of timing for referral. For those requiring transplant, use of monoclonal and polyclonal antibody induction protocols have been associated with improved outcomes. Experience at centers of excellence demonstrates 1 and 5 year patient survival rates of 93 and 78%, respectively with ongoing investigations focusing on lowering long-term causes of graft loss such as chronic rejection or morbidities such as renal dysfunction. Descriptions of tissue, proteomic and genomic technologies to complement traditional methodologies to monitor graft function are emerging.

SUMMARY

Optimal timing for referral of children with intestinal failure and improved medical and surgical therapies increase the opportunity for intestinal adaptation without the need for transplant. For those undergoing transplant, technical and immunologic modifications, developments in graft monitoring, and reduction of long-term morbidities are leading to improved outcomes.

Current perspectives on pediatric intestinal transplantation

Irreversible intestinal failure in children is predominantly caused by surgical conditions such as volvulus, necrotizing enterocolitis, and gastroschisis. Functional intestinal failure from motility disorders such as intestinal pseudo-obstruction or enterocyte dysfunction with microvillus inclusion disease also may require intestine replacement. Approved indications for intestinal transplantation include liver dysfunction, loss of major venous access, frequent central line-related sepsis, and recurrent episodes of severe dehydration despite intravenous fluid management. Surgical options include transplantation of the isolated intestine, combined liver-intestine transplantation, or multivisceral transplantation of the stomach, duodenum, pancreas, and small bowel (with or without the liver). Immunosuppression for intestinal transplantation is based on tacrolimus therapy, often with induction immunosuppression using antilymphocyte antibodies (eg, antithymocyte antibody and alemtuzumab). Experience at centers of excellence demonstrates 1- and 5-year patient survival rates of 95% and 77%, respectively, with ongoing investigations focusing on lowering long-term causes of graft loss such as chronic rejection.

Lessons learned in pediatric small bowel and liver transplantation from living-related donors

BACKGROUND

Children are the primary candidates for intestinal transplant with more than 70% requiring a combined liver-bowel transplant. We report our single-center experience with living donor intestinal transplantation (LDITx) and combined living donor intestinal and liver transplant (CLDILTx) in pediatric patients.

PATIENTS AND METHODS

Between October 2002 and June 2006, 13 living donor intestinal grafts were transplanted in 10 recipients. In five cases CLDILTx was performed. The intestinal grafts consisted of a 150-cm segment of ileum, whereas the liver transplant was completed using standard left lateral grafts.

RESULTS

No complications occurred in any donors. In CLDILTx recipients, the patient survival at 1 and 2 years was 100%, the liver graft survival 100%, and the bowel graft survival 80%; the patient who lost the initial intestinal graft was successfully retransplanted. In LDITx recipients, the patient and graft survival at 1 and 3 years were 60% and 50%, respectively. Two isolated LDITx recipients, both 6 months of age and low body weight (mean, 6 vs. 9 kg) died within 4 months posttransplant. One LDITx recipient developed chronic rejection 3.5 years after the original transplant and died after retransplant. All patients who are alive with functioning grafts are currently on full enteral feeding without need for any intravenous supplementation, except for a recipient of CLDILTx, currently on total parenteral nutrition for late fistula.

CONCLUSIONS

The early outcomes of intestinal transplantation from living donors are promising, particularly for candidates in need of CLDLITx. In this subgroup, the elimination of the high mortality on the cadaver waiting list (approximately 30%) represents a substantial advantage.

Staged approach for abdominal wound closure following combined liver and intestinal transplantation from living donors in pediatric patients

Primary closure of the abdominal wall after combined liver and intestine transplantation from a living donor into a pediatric patient is usually not possible, because of the size of the donor organ, graft edema, and preexisting scars or stomas of the abdominal wall. Closure under tension may lead to abdominal compartment syndrome with vascular compromise and necrosis of the transplanted organ. We describe our experience of abdominal wound closure after liver and intestinal transplant in the pediatric patient using a staged approach. From February 2003 to June 2006, we managed five pediatric liver and intestinal living donor transplant recipients. Because of the large post-transplantation abdominal wall defect, a staged technique of abdominal wound closure was utilized. Initially, an absorbable Polygalactin mesh was sutured around the layer of the defect. As soon as adequate granulation tissue was formed over the mesh a STSG was applied. From the wound stand point all five patients were managed successfully with staged wound closure after transplantation. Granulation tissue filled and covered the mesh within 7.6 wk. A STSG was then used to cover the defect. All infants recovered well and none had a significant wound complication in the immediate post-operative period following STSG. At a mean follow-up of 24 months only one patient developed an entero-cutaneous fistula five months post-transplant. Staged abdominal wall coverage with the use of Polygalactin mesh followed by STSG is a simple and effective technique. A closed wound is achieved in a timely fashion with protection of the viscera. Residual ventral hernia will need to be managed in the future with one of several reconstructive techniques.

Technical refinements in small bowel transplantation

PURPOSE OF REVIEW

This review focuses on the recently described or revised refinements or innovations in small bowel transplantation.

RECENT FINDINGS

Changes in donor selection criteria; cadaveric procurement techniques; organ preservation solutions; management of the recipient abdominal wall; technical modifications, pitfalls and recommendations to be applied during the engraftment as well as intestinal living donation will be covered.

SUMMARY

Intestinal transplantation has evolved over time to become a clinically accepted therapy for patients with intestinal failure. Short- and long-term results have improved. The surgical procedures have been standardized and the applications broaden, but there have been recently published refinements that might affect the future results of clinical intestinal transplantation and guide research.

Simultaneous or sequential combined living donor-intestine transplantation in children

BACKGROUND

Since the report of the first successful living donor combined liver-intestine transplant in pediatric patients, three other cases have been performed. In this article, we describe surgical technique, outcome, and propose a broader application of this procedure using deceased donors.

PATIENTS

Four children of mean age 15.5 months (11-24 months) and weight 9.5 kg (8-10.9 kg) affected by end-stage liver and intestinal failure underwent living donor combined liver-intestine transplant with a left lateral liver and a distal segment of jejunum. In one case, the organs were transplanted simultaneously and in three in staged procedures. In all cases the liver transplant was performed first. The intestine was always transplanted with systemic venous drainage. The biliary anastomosis was a duct-to-duct, a biliodigestive, or a combined one according to the biliary anatomy of the liver graft. The abdomen was routinely closed with a Vicryl mesh followed by a skin graft. A loop graft ileostomy was fashioned for protocol biopsies and taken down within 3 months.

RESULTS

One intestine was lost to generalized ischemia. The child was promptly retransplanted with another living donor graft. All children are alive and well at an average follow-up of 30 months (18-54 months).

CONCLUSIONS

Living donor combined liver-intestine transplant can be performed successfully with excellent early outcome. The in situ splitting technique here described can be applied to obtain grafts for small children from appropriate adult deceased donors.

Present status and future perspectives of intestinal transplantation

Intestinal transplantation (ITx) is the only definitive therapy for irreversible intestinal failure. Owing to the limited short- and long-term graft survival over the years, ITx has been a complementary treatment to home parenteral nutrition. However, the development of intestinal and multivisceral transplantation has been significant over the past 15-20 years owing to the progress in immunosuppressive therapy, refinement of surgical techniques, post-transplant care, intestinal immunology, and immunological as well as anti-infectious monitoring. The improvement of patient- and graft survival over the last few years together with data on the cost effectiveness of ITx, following 2 years after transplantation, may require a redefinition of the indication for ITx.

Combined living-related segmental liver and bowel transplantation for megacystis-microcolon-intestinal hypoperistalsis syndrome

BACKGROUND

Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) is the most severe form of functional intestinal obstruction in the newborn. To date, multivisceral transplantation has been the only accepted treatment modality for these patients, and the results have met with marginal success. We report the first case of a patient affected by MMIHS and cholestatic liver failure treated by a combined living-related liver and intestinal transplant (CLRLITx).

CASE REPORT

The patient was a 1-year-old Hispanic girl born with MMIHS and maintained on total parenteral nutrition since birth. Once liver failure developed, she was referred for evaluation for possible CLRLITx. The patient's mother volunteered as the donor. The left lateral segment was used for the liver transplant. The intestinal graft consisted of the terminal 180 cm of the ileum with a single vascular pedicle. Initially, the patient continued to have severe gastroparesis; however, by 8 months posttransplant, stomach function had returned to normal. Currently, at 2 years posttransplant, she is tolerating an oral diet with gastric tube supplementation. Results of absorption studies are within normal, and she has shown catch-up growth.

CONCLUSION

A CLRLITx can be a viable alternative for infants diagnosed with MMIHS. This procedure can help avoid the 25% wait-list mortality for children who are in need of a combined transplant.

Neonatal short bowel syndrome outcomes after the establishment of the first Canadian multidisciplinary intestinal rehabilitation program: preliminary experience

BACKGROUND

A multidisciplinary intestinal rehabilitation team has been in place at our institution for 3 years. Our goal was to compare the preliminary outcomes of neonates with short bowel syndrome before with those after the establishment of our formalized intestinal failure program (Group for the Improvement of Intestinal Function and Treatment [GIFT]).

METHODS

We conducted a retrospective analysis of our intestinal failure registry comparing preGIFT (1997-1999) with GIFT (2003-2005) outcomes.

RESULTS

Fifty-four patients (mean gestational age = 33.5 weeks) were included in the GIFT cohort, and 40 patients (mean gestational age = 30.7 weeks) formed the preGIFT cohort. Overall mortality rates (33.3% vs 37.5%, P = .84) were equivalent in the 2 cohorts, although fewer patients died of liver failure after the establishment of the GIFT. Among those with liver failure, the mortality in the preGIFT group was 9/10 as compared with that of 6/13 in the GIFT group (P = .03). The decrease in liver-related deaths was partly attributable to earlier referral for and increased survival to transplant (4 for the GIFT group vs 0 for the preGIFT group).

CONCLUSIONS

Analysis of the preliminary outcomes of the GIFT program suggests that the natural history of neonatal short bowel syndrome remains unaltered to date despite a coordinated approach to care. However, improved communication and integration with the transplant service have resulted in earlier assessment, increased rates of transplantation, and decreased mortality from liver failure.

Current status of transplantation of the small intestine

The evolution of small bowel transplantation has been significant over the past 20 years to the point at which it can now be considered a viable and often successful option in the treatment of many forms of short bowel syndrome. A refinement of surgical techniques, improved immunosuppression, enhanced understanding of gut immunology, and better treatment and prevention of complications have contributed to a marked improvement in graft and patient survival. Whereas this transplant population is still beset with many potential complications after isolated bowel or multivisceral transplantation and long-term graft survival (like with other solid organ transplants) remains a challenge, the future holds promise for a continuation of the current positive trend of improvement in several areas.

The establishment of a new en bloc combined liver-small bowel transplantation model in rats

In order to facilitate preclinical research, we established a new combined liver-small bowel transplantation rat model. Male inbred Wistar rats were chosen as donors and recipients. An en bloc liver-small bowel graft was harvested. During the donor operation, the inferior vena cava in the chest was removed to be used as an interpositional venous graft to anastomose to the portal vein. In the recipient operation the portal veins of donor and recipient were quickly anastomosed using a cuff technique instead of the traditional suture method. Rearterialization was achieved by anastomosing the superior mesenteric artery of graft to the right renal artery of the recipient. The recipient small bowel was resected and intestinal continuity restored simultaneously by two end-to-end anastomoses. The postoperative 5-day survival rate was 77.5% (31/40) and 60-day survival rate, 72.5% (29/40). Recipient rats that tolerated the operation remained healthy. Liver and renal function was normal. The liver and intestinal grafts showed normal histological architecture in all rats surviving for 2 months postoperatively. Our results demonstrated that the present model is feasible, allowing preclinical experimental research on combined liver-small bowel transplantation.

Living related segmental bowel transplantation: from experimental to standardized procedure

INTRODUCTION

Living donor bowel transplantation has recently emerged as a valuable alternative to cadaver bowel transplant. We herein present our single-center experience with this procedure.

MATERIALS AND METHODS

From April 1998 to October 2004, 12 living donor intestinal transplants were performed in 11 patients (7 males, 4 females; average age, 26 years). Four of the patients were children under 5 years. A segment of distal ileum 150 to 180 cm long in pediatric recipients and 200 cm long in adult was used. The immunosuppressive protocol consisted of induction with thymoglobulin and maintenance with tacrolimus with or without mycophenolate mofetil and steroids.

RESULTS

All donors recovered well and did not experience any early or late complications. The overall 1- and 3-year patient survival was 82% with a graft survival of 75%. In the last 8 patients, transplanted after January 2000, the 1-year patient and graft survival has been 100% and 88%, respectively. The median hospital stay was 36 days (range, 13-290 days). During the first year after transplant only, the patient who received a totally mismatched graft experienced one episode of rejection (8%). All the surviving patients are currently supported by enteral diet without fluid requirements.

CONCLUSIONS

Living donor bowel transplantation is a valuable strategy in the treatment of irreversible intestinal failure. The results have improved over the years thanks to increased experience of the team.

Small bowel transplantation

Until very recently, outcomes from small bowel transplantation (SBTx) lagged behind those in liver, heart, and kidney transplantation because of the magnitude of the immunologic burden; the strong expression of histocompatibility antigens; and the contamination in grafts by bacterial organisms. With novel techniques of immune-induction therapies, such as recipient "preconditioning" with lymphocyte reduction, followed by the more subtle use of immunosuppression-based single-agent tacrolimus, graft and host 1-year survival is now over 90% in the most active US centers, a finding that parallels the outcomes in liver and kidney transplantation. In contrast to the alternative therapy for permanent intestinal failure, home total parenteral nutrition (TPN), SBTx improves quality of life and restores digestive and absorptive function, making patients nutritionally autonomous. With survival beyond 1 to 3 years, the procedure is cost-effective. Current results support expansion of the indications for SBTx from use as salvage therapy for patients with TPN failure to preemptive therapy for patients at risk of developing TPN failure.

Immuno-protective effect of liver on small bowel in combined transplantation of liver and small bowel

AIM: To develop a new combined transplan-tation model of liver and small bowel in rats, and to investigate the protective effect of trans-planted liver on transplanted small bowel.

METHODS: Closed colony Sprague Dawley rats and inbred Wistar rats were included in this study. Five groups were designed: isogene small bowel transplant group (A), isogene liver transplant group (B), xenogene small bowel transplant group (C), xenogene liver transplant group (D), combined transplant of liver and small bowel group (E). Only Wistar rats were used in group A and B, while SD and Wistar rats were used as donors and recipients respectively in group C, D and E. During the combined transplantation of liver and small bowel (CTLS) for the donors, inferior vena cava in chest was cut to construct a muff in the lateral wall of portal vein and cuff was placed. During the operation for the recipients, portal veins of the donors and recipients were connected using cuff technique, and re-arterialization was completed by anastomosing the superior mesenteric artery of graft with the right kidney artery of the recipients. Randomly selected 4 rats from each group were sacrificed on postoperative days (POD) 5, 7 and 14, and grafts were sampled. The rejection of graft was investigated through histopathological analysis, and the apoptosis of the cells of graft were evaluated by TUNEL.

RESULTS: The survival rate of CTLS was 73.3% (22/30). The pathological changes of ischemia and reperfusion injury were observed in group A and B, and the numbers of apoptotic cells in the grafts were decreased with the prolonging of time. However, acute rejection after transplantation appeared in group C and D, and there were more apoptotic cells in the grafts. Mild, moderate and severe acute rejection occurred on POD 5, 7 and 14, respectively in group C, while only mild or severe acute rejection appeared in group E. Furthermore, the number of apoptotic cells in the grafts of group E was markedly decreased on POD 14 in comparison with that of group C (16.9 ± 4.3 vs 20.5 ± 6.3, P < 0.05). The degrees of acute rejection after transplantation and cell apoptosis of the grafts were not significantly different between group D and E.

CONCLUSION: The technique used in this study is feasible for establishment of CTLS model, and the transplanted liver can protect the transplanted intestinal graft from rejection in CTLS.