Evolution of clinical intestinal transplantation: improved outcome and cost effectiveness

Cost-effectiveness of Intestinal Transplantation Compared to Parenteral Nutrition in Adults

BACKGROUND

Intestinal transplantation (ITx) is the most expensive abdominal organ transplant. Detailed studies about exact costs and cost-effectiveness compared to home parenteral nutrition (HPN) therapy in chronic intestinal failure are lacking. The aim is to provide an in-depth analysis of ITx costs and evaluate cost-effectiveness compared to HPN.

METHODS

To calculate costs before and after ITx, costs were analyzed in 12 adult patients. To calculate the costs of patients with uncomplicated chronic intestinal failure, 28 adults, stable HPN patients were studied. Total costs including surgery, admissions, diagnostics, HPN therapy, medication, and ambulatory care were included. Median (range) costs are given.

RESULTS

Costs before ITx were €69 160 (€60 682-90 891) in year 2, and €104 146 (€83 854-186 412) in year 1. After ITx, costs were €172 133 (€122 483-351 407) in the 1st year, €40 619 (€3905-113 154) in the 2nd year, and dropped to €15 743 (€4408-138 906) in the 3rd year. In stable HPN patients, the costs were €83 402 (€35 364-169 146) in the 1st year, €70 945 (€31 955-117 913) in the 2nd year, and stabilized to €60 242 (€29 161-238 136) in the 3rd year.

CONCLUSIONS

ITx, although initially very expensive, is cost-effective compared to HPN in adults by year 4, and cost-saving by year 5.

Twenty Years of Gut Transplantation for Chronic Intestinal Pseudo-obstruction: Technical Innovation, Long-term Outcome, Quality of Life, and Disease Recurrence

OBJECTIVE

To define long-term outcome, predictors of survival, and risk of disease recurrence after gut transplantation (GT) in patients with chronic intestinal pseudo-obstruction (CIPO).

BACKGROUND

GT has been increasingly used to rescue patients with CIPO with end-stage disease and home parenteral nutrition (HPN)-associated complications. However, long-term outcome including quality of life and risk of disease recurrence has yet to be fully defined.

METHODS

Fifty-five patients with CIPO, 23 (42%) children and 32 (58%) adults, underwent GT and were prospectively studied. All patients suffered gut failure, received HPN, and experienced life-threatening complications. The 55 patients received 62 allografts; 43 (67%) liver-free and 19 (33%) liver-contained with 7 (13%) retransplants. Hindgut reconstruction was adopted in 1993 and preservation of native spleen was introduced in 1999. Immunosuppression was tacrolimus-based with antilymphocyte recipient pretreatment in 41 (75%).

RESULTS

Patient survival was 89% at 1 year and 69% at 5 years with respective graft survival of 87% and 56%. Retransplantation was successful in 86%. Adults experienced better patient (P = 0.23) and graft (P = 0.08) survival with lower incidence of post-transplant lymphoproliferative disorder (P = 0.09) and graft versus host disease (P = 0.002). Antilymphocyte pretreatment improved overall patient (P = 0.005) and graft (P = 0.069) survival. The initially restored nutritional autonomy was sustainable in 23 (70%) of 33 long-term survivors with improved quality of life. The remaining 10 recipients required reinstitution of HPN due to allograft enterectomy (n = 3) or gut dysfunction (n = 7). Disease recurrence was highly suspected in 4 (7%) recipients.

CONCLUSIONS

GT is life-saving for patients with end-stage CIPO and HPN-associated complications. Long-term survival is achievable with better quality of life and low risk of disease recurrence.

Management of Five Hundred Patients With Gut Failure at a Single Center: Surgical Innovation Versus Transplantation With a Novel Predictive Model

OBJECTIVE(S)

To define the evolving role of integrative surgical management including transplantation for patients gut failure (GF).

METHODS

A total of 500 patients with total parenteral nutrition-dependent catastrophic and chronic GF were referred for surgical intervention particularly transplantation and comprised the study population. With a mean age of 45 ± 17 years, 477 (95%) were adults and 23 (5%) were children. Management strategy was guided by clinical status, splanchnic organ functions, anatomy of residual gut, and cause of GF. Surgery was performed in 462 (92%) patients and 38 (8%) continued medical treatment. Definitive autologous gut reconstruction (AGR) was achievable in 378 (82%), primary transplant in 42 (9%), and AGR followed by transplant in 42 (9%). The 84 transplant recipients received 94 allografts; 67 (71%) liver-free and 27 (29%) liver-contained. The 420 AGR patients received a total of 790 reconstructive and remodeling procedures including primary reconstruction, interposition alimentary-conduits, intestinal/colonic lengthening, and reductive/decompressive surgery. Glucagon-like peptide-2 was used in 17 patients.

RESULTS

Overall patient survival was 86% at 1-year and 68% at 5-years with restored nutritional autonomy (RNA) in 63% and 78%, respectively. Surgery achieved a 5-year survival of 70% with 82% RNA. AGR achieved better long-term survival and transplantation better (P = 0.03) re-established nutritional autonomy. Both AGR and transplant were cost effective and quality of life better improved after AGR. A model to predict RNA after AGR was developed computing anatomy of reconstructed gut, total parenteral nutrition requirements, cause of GF, and serum bilirubin.

CONCLUSIONS

Surgical integration is an effective management strategy for GF. Further progress is foreseen with the herein-described novel techniques and established RNA predictive model.

Indications of Intestinal Transplantation

"The intestinal transplantation is reserved for patients with life-threatening complications of permanent intestinal failure or underlying gastrointestinal disease. The choice of the allograft for a particular patient depends on several factors and the presence of concurrent organ failure, and availability of the donor organs, and specialized care. Combined liver and intestinal transplant allows for patients who have parenteral nutrition-associated liver disease a possibility of improved quality of life and nutrition as well as survival. Intestinal transplantation has made giant strides over the past few decades to the present era where current graft survivals are comparable with other solid organ transplants."

Pre-emptive Intestinal Transplant: The Surgeon's Point of View

Pre-emptive transplantation is a well-established practice for certain types of end-organ failure such as in the use of kidney transplantation. For irreversible intestinal failure, total parenteral nutrition (TPN) remains the gold standard, due to the suboptimal long-term results of intestinal transplantation. As such, the only role for pre-emptive transplantation, if at all, will be for patients identified to be at high risk of complications and mortality while on definitive long-term TPN. In these patients, the timing of early listing and transplantation could become life-saving, taking into account that mortality on the waiting list is still the highest for intestinal candidates. The development of simulation models or pre-transplant scoring systems could help in selecting patients based on potential outcome on TPN or with transplantation, and recent reports from high-volume centers identify few underlying pathologic conditions and some TPN complications as at higher risk of increased morbidity and mortality. A pre-emptive transplant could be used as a rehabilitative procedure in a well-selected case-by-case scenario, among TPN patients at risk of liver failure, repeated central line infections, mesenteric infarction, short bowel syndrome (SBS) <50 cm or with end stoma, congenital mucosal disease, desmoid tumors: These conditions must be carefully evaluated, not to underestimate the clinical stage nor to over-estimate the impact of a temporary situation. At the present time, diseases with a variable and unpredictable course, such as intestinal dysmotility disorders, or quality of life and financial issues are still far from being considered as indications for a pre-emptive transplant.

Intestinal rehabilitation for children with intestinal failure is cost-effective: a simulation study

BACKGROUND

Children with intestinal failure (IF) depend on parenteral nutrition (PN). The goal in the treatment of IF is to wean children off PN through intestinal rehabilitation (IR). Although the healthcare burden of IF is enormous, to our knowledge there has been no previous cost-effectiveness analysis in pediatric IF including IR.

OBJECTIVE

We sought to determine the cost-effectiveness of IR in terms of costs and life-years.

DESIGN

We simulated the treatment of IF in children in a discrete-event model. Data for this model were derived from patient records, the Dutch Registry of Intestinal Failure and Transplantation, the Intestinal Transplant Registry, and the literature. The time horizon of the model was 40 y. Simulated patients were enrolled at a rate of 40 patients/mo for 10 y. Actual costs were calculated for hospital admissions, surgical interventions, endoscopies, PN, and immunosuppressive medication. We evaluated the cost-effectiveness of IR by comparing 1 scenario with IR with 1 scenario without IR. In the scenario with IR, a proportion of patients who represented those with the ability to wean off PN were assigned to IR. In the scenario without IR, all patients progressed to home PN (HPN). In both scenarios, a proportion of patients receiving HPN were eventually eligible for an intestinal transplantation.

RESULTS

IR prolonged survival; the mean number of life-years per patient was 19.4 in the scenario with IR compared with 18.2 in the scenario without IR. Average total costs per patient were €819,292 in the scenario with IR compared with €1,176,830 in the scenario without IR (equivalent to 1,129,230 US$ and 1,622,025 US$, respectively, in January 2014); costs mainly included hospital admissions and PN.

CONCLUSIONS

On the basis of our simulations, we concluded that IR improved the survival of children with IF and was associated with cost savings. Therefore, we consider IR to be a cost-effective treatment for children with IF.

Current status of intestinal and multivisceral transplantation

Clinical-nutritional autonomy is the ultimate goal of patients with intestinal failure (IF). Traditionally, patients with IF have been relegated to lifelong parenteral nutrition (PN) once surgical and medical rehabilitation attempts at intestinal adaptation have failed. Over the past two decades, however, outcome improvements in intestinal transplantation have added another dimension to the therapeutic armamentarium in the field of gut rehabilitation. This has become possible through relentless efforts in the standardization of surgical techniques, advancements in immunosuppressive therapies and induction protocols and improvement in postoperative patient care. Four types of intestinal transplants include isolated small bowel transplant, liver-small bowel transplant, multivisceral transplant and modified multivisceral transplant. Current guidelines restrict intestinal transplantation to patients who have had significant complications from PN including liver failure and repeated infections. From an experimental stage to the currently established therapeutic modality for patients with advanced IF, outcome improvements have also been possible due to the introduction of tacrolimus in the early 1990s. Studies have shown that intestinal transplant is cost-effective within 1-3 years of graft survival compared with PN. Improved survival and quality of life as well as resumption of an oral diet should enable intestinal transplantation to be an important option for patients with IF in addition to continued rehabilitation. Future research should focus on detecting biomarkers of early rejection, enhanced immunosuppression protocols, improved postoperative care and early referral to transplant centers.

Is There a Role for Living Donor Intestine Transplants?

The use of living donors with intestinal transplantation is controversial because it may not significantly improve candidate access to organs when intestine-only grafts are needed, and may involve excessive donor risk when combined liver-intestine grafts are required. Although limited data are available for comparison at this time, graft and patient survival rates for intestinal transplantations using living donors are no different than for deceased donor transplantations. Potential benefits that may be provided to the intestine transplant recipient through the use of living donors include better HLA matching, shorter ischemia times, better bowel preparation, and better opportunities for introducing immunomodulatory strategies. Conversely, living intestine donors are at risk for mortality, significant morbidity, financial loss, and psychologic trauma. The long-term outcomes of living intestine donors have not yet been reported. Ultimately, these data are essential before the wider use of living donors can be advocated for intestinal transplantation.

Management of Crohn's Disease in the New Era of Gut Rehabilitation and Intestinal Transplantation

Despite recent therapeutic advances, patients with Crohn's disease (CD) continue to experience high recurrence with cumulative structural damage and ultimate loss of nutritional autonomy. With short bowel syndrome, strictures, and enteric fistulae being the underlying pathology, CD is the second common indication for home parenteral nutrition (HPN). With development of intestinal failure, nutritional management including HPN is required as a rescue therapy. Unfortunately, some patients do not escape the HPN-associated complications. Therefore, the concept of gut rehabilitation has evolved as part of the algorithmic management of these patients, with transplantation being the ultimate life-saving therapy. With type 2 intestinal failure, comprehensive rehabilitative measures including nutritional care, pharmacologic manipulation, autologous reconstruction, and bowel lengthening is often successful, particularly in patients with quiescent disease. With type 3 intestinal failure, transplantation is the only life-saving treatment for patients with HPN failure and intractable disease. With CD being the second common indication for transplantation in adults, survival outcome continues to improve because of surgical innovation, novel immunosuppression, and better postoperative care. Despite being a rescue therapy, the procedure has achieved survival rates similar to other solid organs, and comparable to those who continue to receive HPN therapy. With similar technical, immunologic, and infectious complications, survival is similar in the CD and non-CD recipients. Full nutritional autonomy is achievable in most survivors with better quality of life and long-term cost-effectiveness. CD recurrence is rare with no impact on graft function. Further progress is anticipated with new insights into the pathogenesis of CD and mechanisms of transplant tolerance.

The concept of gut rehabilitation and the future of visceral transplantation

In the 1990s, the introduction of visceral transplantation fuelled interest in other innovative therapeutic modalities for gut rehabilitation. Ethanol lock and omega-3 lipid formulations were introduced to reduce the risks associated with total parenteral nutrition (TPN). Autologous surgical reconstruction and bowel lengthening have been increasingly utilized for patients with complex abdominal pathology and short-bowel syndrome. Glucagon-like peptide 2 analogue, along with growth hormone, are available to enhance gut adaptation and achieve nutritional autonomy. Intestinal transplantation continues to be limited to a rescue therapy for patients with TPN failure. Nonetheless, survival outcomes have substantially improved with advances in surgical techniques, immunosuppressive strategies and postoperative management. Furthermore, both nutritional autonomy and quality of life can be restored for more than two decades in most survivors, with social support and inclusion of the liver being favourable predictors of long-term outcome. One of the current challenges is the discovery of biomarkers to diagnose early rejection and further improve liver-free allograft survival. Currently, chronic rejection with persistence of preformed and development of de novo donor-specific antibodies is a major barrier to long-term graft function; this issue might be overcome with innovative immunological and tolerogenic strategies. This Review discusses advances in the field of gut rehabilitation, including intestinal transplantation, and highlights future challenges. With the growing interest in individualized medicine and the value of health care, a novel management algorithm is proposed to optimize patient care through an integrated multidisciplinary team approach.

[Short bowel syndrome in Germany. Estimated prevalence and standard of care]

OBJECTIVE

As data about prevalence and standard of care in short bowel syndrome (SBS) are not available for Germany, this study estimated the prevalence and assessed the medical infrastructure to potentially improve care of SBS patients.

METHODS

In a validated approach for prevalence estimation in rare diseases, a randomized census of 478 size-stratified hospitals with surgical, internal medicine and pediatric departments was conducted to estimate SBS prevalence. The number of SBS patients, specialized outpatient clinics and caregiver expertise were assessed.

RESULTS

The response rate was 85 % of randomized hospitals (405/478). Strata-derived estimation yielded a total of 2,808 SBS patients in Germany for 2011/2012 (95 % CI: 1750.3865), translating into a prevalence estimation for 34/million inhabitants (95 % CI: 21.47). Overall expertise in SBS treatment was only rated "satisfactory" by most caregivers. While 86 specialized outpatient clinics were identified, there was no central registry to access these resources.

CONCLUSION

Short bowel syndrome, with a newly estimated prevalence of 34/million inhabitants is not a very rare medical condition in Germany. The interdisciplinary approach needed for optimal care for SBS patients would be greatly facilitated by a central registry.

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.

Six-month incidence of bloodstream infections in intestinal transplant patients

BACKGROUND

Intestinal transplantation has emerged as an established treatment for life-threatening intestinal failure. The most common complication and cause of death is infection. Risk of infection is highest during the first 6 months, as a consequence of maximal immunosuppression, greater than that required for any other organ allograft.

METHODS

We performed a retrospective chart review of all (56) adult and pediatric (<18 years) small bowel transplant patients at our institution between November 2003 and July 2007, and analyzed the 6-month post-transplant incidence of bloodstream infections (BSIs). We evaluated multiple risk factors, including inclusion of a colon or liver, total bilirubin >5, surgical complications, and acute rejection.

RESULTS

A BSI developed in 34 of the 56 patients, with a total of 85 BSI episodes. Of these BSI episodes, 65.9% were due to gram-positive organisms, 34.1% gram-negative organisms, and 2.4% due to fungi. The most common isolates were Enterococcus species, Enterobacter species, Klebsiella species, and coagulase-negative staphylococci. Inclusion of the liver and/or a preoperative bilirubin >5 mg/dL appeared to increase the incidence of BSI (P = 0.0483 and 0.0005, respectively). Acute rejection and colonic inclusion did not appear to affect the incidence of BSI (P = 0.9419 and 0.8248, respectively). The BSI incidence was higher in children (P = 0.0058).

CONCLUSIONS

BSIs are a common complication of intestinal transplantation. Risk factors include age <18, inclusion of the liver, and pre-transplant bilirubin >5. Acute rejection and colon inclusion do not appear to be associated with increased BSI risk.

Different ischemic preconditioning regimens affecting preservation injury of intestines

Decreasing ischemia-reperfusion injury in intestinal transplantation is of paramount importance for improving graft recovery and function. This study explores the ability of two ischemic preconditioning (IPC) regimens to reduce preservation injury. Sprague-Dawley rats were divided into 3 groups (n = 11 each). In the controls (group C), intestinal grafts were harvested and preserved. IPC was performed either through 4 cycles of mesenteric ischemia of 4 min each followed by 10 min of reperfusion (group BIPC) or 2 ischemic cycles of 12 min each followed by 10 min of reperfusion (group LIPC). Grafts were stored in histidine-tryptophan-ketoglutarate, and samples were taken 0, 3, 6, 9, 12, 18, and 24 h after preservation. Preservation injury was scored using the Park/Chiu scale. Goblet cells (GC), enteroendocrine cells (EEC) and serotonin-producing EEC (SPEEC) were studied for evaluation of the graft conditions. Group C had the most advanced preservation injury followed by group BIPC. GC count was lowest in group C, followed by BIPC. Comparison between groups BIPC and LIPC showed superior parameters (preservation injury, GC, EEC, and SPEEC) in LIPC. In conclusion, an IPC regimen of 2 ischemic cycles of 12 min each followed by 10 min of reperfusion distinctly decreased the preservation injury of intestinal grafts compared with non-manipulated grafts.

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.

Therapeutic efficacy of intestinal and multivisceral transplantation: survival and nutrition outcome

The clinical introduction of intestinal transplantation has added a new dimension and offered a valid therapeutic option for patients with irreversible intestinal failure. In the year 2000, the Center for Medicare & Medicaid Services (CMS) recognized intestinal, combined liver-intestinal, and multivisceral transplantation as the standard of care for patients with irreversible intestinal and parenteral nutrition (PN) failure. Accordingly, the indications for the procedure are currently limited to those who develop life-threatening PN complications. However, a recent improvement in survival similar to other solid organ transplant recipients should justify lifting the current restricted criteria, and the procedure should be considered before the development of PN failure. Equally important is the awareness of the recent evolution in nutrition management and outcome after transplantation. Early and progressive enteral feeding using a complex polymeric formula is safe and effective after successful transplantation. Full nutrition autonomy is universally achievable among most intestinal and multivisceral recipients, with enjoyment of unrestricted oral diet. Such a therapeutic benefit is commonly maintained among long-term survivors, with full rehabilitation and restoration of quality of life.

Treatment of intestinal failure: intestinal transplantation

Over the past 15 years, intestinal transplantation for the treatment of intestinal failure has changed from a desperate last-ditch effort into a standard therapy for which a good outcome is expected. Patient survival after intestinal transplantation has improved in the past 3-5 years and now approaches that of other solid organ allograft recipients, including liver and kidney, and is similar to survival on permanent therapy with parenteral nutrition. Complications are more common and often more severe during the initial hospitalization period after intestinal transplantation than they are after transplantation of other solid organs. After intestinal transplantation the initial hospitalization period is, therefore, usually 3-8 weeks long. Nearly all patients discharged after intestinal transplantation have good allograft function and have been weaned from total parenteral nutrition. The cost of the initial hospitalization period is one to two times the cost of permanent total parenteral nutrition for 1 year, which means that, in most cases, intestinal transplantation is cost-saving within 2 years of transplantation. In addition, quality of life after intestinal transplantation, as determined by standardized quality of life measures, is good or normal.

Is intestinal transplantation now an alternative to home parenteral nutrition?

Patients with irreversible intestinal failure and complications of parenteral nutrition should now be routinely considered for small intestine transplantation. Despite attempts for >40 years immunological graft intolerance presented an impenetrable barrier to successful engraftment until the development in the late 1970s of the powerful calcineurin-inhibitor immunosuppressive agents. Their use over the last 17 years has led to small intestinal transplantation being generally considered as a routine option for patients with irreversible intestinal failure and failing parenteral nutrition. The 1-year patient survival rates (%) are now excellent for renal (95), liver (78), heart (82) and lung (75) transplantation. In contrast, survival rates for small intestinal transplantation have been slow to improve, although they are now approaching those for lung and liver transplantation (intestine 78%, intestine and liver 60%, multivisceral 66%), and well-performing centres report recent 1-year graft survival rates as high as 92%. Patient 5-year survival (%) has also improved (intestine alone 50, intestine and liver 50 and multivisceral 62) and compares increasingly favourably with renal (85), liver (67), heart (67) and lung (46). Currently, small intestinal transplantation is reserved for patients with irreversible small intestinal failure who have a poor prognosis on parenteral nutrition. However, as 5-year patient survival following intestinal transplantation approaches that for parenteral nutrition there will be increasing pressure to offer this modality of treatment as an alternative to parenteral nutrition, especially for those patients who have a poor quality of life as a result of parenteral nutrition.

Role and significance of plasma citrulline in the early phase after small bowel transplantation in pigs

A reliable serological marker of acute cellular rejection (ACR) after small bowel transplantation (SBTx) is still missing. Plasma citrulline level (PCL) reflects the functional integrity of intestinal mucosa which is partially lost during ACR. The aim of our study was to investigate the role of PCL as marker of ACR after SBTx. Eighteen German landrace pigs were used and divided into three groups. Group 1 (G1), autologous SBTx (n = 4) as control; group 2 (G2), allogeneic SBTx without immunosuppression (IS) (n = 7) and group 3 (G3), allogeneic SBTx with IS (n = 7). IS consisted of tacrolimus and steroids without induction treatment. Observation period was 14 days. Mucosal biopsies were obtained intraoperatively and daily using a Thiry-Vella loop. ACR was differentiated into indeterminate, mild, moderate and severe using a standardized grading schema. PCL was measured daily. An ACR onset occurred generally from postoperative day 4 both in G2 and G3 as mild form and developed differently in the two groups: moderate to severe in G2 and indeterminate to mild in G3. A significant decline of PCL occurred only in cases of moderate and severe ACR, but not in cases of indeterminate and mild ACR. The PCL failed as a marker in the early diagnosis of ACR and became reliable only when advanced mucosal damage was present.

Nutrition and quality of life following small intestinal transplantation

BACKGROUND

The outcome from small bowel transplantation (SBTx) has improved progressively over the past decade raising questions as to whether indications should be broadened from those currently followed based on "TPN (total parenteral nutrition) failure."

OBJECTIVE AND METHODS

To assess current outcome, we studied the effect of transplantation on nutritional autonomy, organ function, and quality of life (QoL) measured by a validated self-administered questionnaire containing 26 domains and 130 questions, for a minimum of 12 months in a cohort of 46 consecutively transplanted patients between June 2003 and July 2004. The majority of transplanted patients (76%) had intestinal failure because of extreme short bowel, the remainder having either chronic pseudo-obstruction or porto-mesenteric vein thrombosis (PMVT). All but the PMVT patients were dependent on home TPN (HPN) (median 2, range 0-25 yr) and had developed serious recurrent infective complications with (25%) or without central vein thrombosis and liver failure. Sixty-one percent received a liver in addition to a small intestine.

RESULTS

Follow-up was for a mean of 21 (range 12-36) months. Five patients died, two with chronic graft rejection. All the remaining patients have graft survival with an average of 1.2 (range 0-5) episodes of acute rejection. All patients were weaned from TPN by a median of 18 days (range 1-117 days) and from tube feeding by day 69 (range 22-272 days). There was a significant improvement in overall assessment of QoL and in 13 of 26 of the specific domains examined.

CONCLUSION

Our results confirm the claim that a new era has dawned for SBTx, such that, with continued progress, it can potentially become an alternative to HPN for the management of permanent intestinal failure, rather than a last-chance treatment for "TPN failure."

Short bowel syndrome: parenteral nutrition versus intestinal transplantation. Where are we today?

Current management of short bowel syndrome (SBS) revolves around the use of home TPN (HPN). Complications include liver disease, catheter-related infections or occlusions, venous thrombosis, and bone disease. Patient survival with SBS on TPN is 86% and 75% at 2 and 5 years, respectively. Surgical management of SBS includes nontransplant surgeries such as serial transverse enteroplasty and reanastomosis. Small bowel transplant has become increasingly popular for management of SBS and is usually indicated when TPN cannot be continued. Posttransplant complications include graft-versus-host reaction, infections in an immunocompromised patient, vascular and biliary diseases, and recurrence of the original disease. Following intestinal-only transplants, patient and graft survival rate is 77% and 66% after 1 year. After 5 years the survival figures are 49% and 34%, respectively. Future improvements in survival and quality of life will enhance small bowel transplant as a viable treatment option for patients with SBS.

Small intestine transplantation today

INTRODUCTION

Intestinal transplantation has become a life-saving therapy in patients with irreversible loss of intestinal function and complications of total parenteral nutrition.

DISCUSSION

The patient and graft survival rates have improved over the last years, especially after the introduction of tacrolimus and rapamycin. However, intestinal transplantation is more challenging than other types of solid organ transplantation due to its large amount of immune competent cells and its colonization with microorganisms. Moreover, intestinal transplantation is still a low volume procedure with a small number of transplanted patients especially in Germany. A current matter of concern is the late referral of intestinal transplant candidates.

CONCLUSION

Thus, patients often present after onset of life-threatening complications or advanced cholestatic liver disease. Earlier timing of referral for candidacy might result in further improvement of this technique in the near future.

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.

An Economic Evaluation of Pediatric Small Bowel Transplantation in the United Kingdom

BACKGROUND

Small bowel transplantation (SBTx) offers an alternative to parenteral nutrition (PN) for the treatment of chronic intestinal failure in children: this study estimated its cost-effectiveness in the early phase of a U.K. program.

METHODS

Children assessed for SBTx were categorized as: 1) requiring SBTx following PN-related complications (n=23), 2) stable at home not requiring SBTx (n=24), and 3) terminally ill and unsuitable for SBTx (n=6). Costs were estimated from detailed resource-use data. Two comparisons were used for effectiveness: actual survival following transplantation (n=14) compared to: 1) estimated survival without transplantation using a prognostic model, and 2) the waiting list experiences of all patients listed for SBTx (n=23).

RESULTS

Mean costs up to 30 months were pounds sterling 207,000 for those transplanted or on the waiting list, pounds sterling 159,000 for those stable on home PN, and pounds sterling 56,000 for those terminally ill. The prognostic model estimated a mean survival gain from transplantation of 0.12 years over 30 months, and suggested that transplantation was cost-saving. The second approach suggested that transplantation reduced survival by 0.24 years at an additional cost of pounds sterling 131,000.

CONCLUSIONS

Firm conclusions on cost-effectiveness of SBTx are not possible given the two different estimates. The prognostic model approach (suggesting that pediatric SBTx may provide a small survival benefit at a small reduction in costs) should be less subject to bias, but the model requires external validation. Meanwhile, children at risk of fatal PN-complications should be given the opportunity to receive a SBTx only within a continuing formal assessment of the technology.

Mechanical Extension Implants for Short-Bowel Syndrome

Short-bowel syndrome (SBS) is a rare, potentially lethal medical condition where the small intestine is far shorter than required for proper nutrient absorption. Current treatment, including nutritional, hormone-based, and surgical modification, have limited success resulting in 30% to 50% mortality rates. Recent advances in mechanotransduction, stressing the bowel to induce growth, show great promise; but for successful clinical use, more sophisticated devices that can be implanted are required. This paper presents two novel devices that are capable of the long-term gentle stressing. A prototype of each device was designed to fit inside a short section of bowel and slowly extend, allowing the bowel section to grow approximately double its initial length. The first device achieves this through a dual concentric hydraulic piston that generated almost 2-fold growth of a pig small intestine. For a fully implantable extender, a second device was developed based upon a shape memory alloy actuated linear ratchet. The proof-of-concept prototype demonstrated significant force generation and almost double extension when tested on the benchtop and inside an ex-vivo section of pig bowel. This work provides the first steps in the development of an implantable extender for treatment of SBS.

Cost and quality of life after intestinal transplantation

Intestinal transplantation has become a standard treatment for intestinal failure in patients with life-threatening complications of TPN. Although the long-term survival of patients with continued parenteral nutrition is higher than after intestinal transplantation, the 1 and 2 year survival is comparable. Here we examine other aspects of the treatment options available for patients with intestinal failure including the cost of the therapy and the quality of life. The cost of parenteral nutrition compared to intestinal transplantation reveals that transplantation is cost-effective in patients that maintain graft function within 1 to 3 years after surgery. The quality of life after transplantation is probably equal to or better than quality of life on TPN and children report quality of life similar to normal school children. Although currently reserved for those with life-threatening complications, intestinal transplantation may soon be an option for any patient permanently dependent on parenteral nutrition.

Oxygen consumption, pCO2 gradients and regional blood flow distribution in an alternative model of intestinal autotransplantation

BACKGROUND

Postoperative complications after intestinal transplantation can be attributed to hypothermic storage and reperfusion injury. Our objective was to evaluate, in an alternative model of intestinal autotransplantation, the initial effects of isolated intestinal hypothermic perfusion (at 4 degrees C, IHP) on mucosal and serosal blood flow distribution and correlate these findings with other systemic and regional markers of mesenteric ischemia. In addition, we sought to obtain evidence that intestinal pCO2 measurement can be a useful method for monitoring graft perfusion and early histological changes after small bowel transplantation.

MATERIALS AND METHODS

Eight dogs (23.3+/-1.1 kg) were submitted to a in situ IHP for 30 min, followed by a 180-min reperfusion period. Cardiac output, mesenteric vein, and intestinal serosal blood flows (SMVBF and SBF, ultrasonic flowprobe); intestinal mucosal-arterial pCO2 gradient (Dt-apCO2, tonometry); and O2-derived variables were evaluated.

RESULTS

IHP induced a reduction in SMVBF (579+/-53 to 321+/-10 mL/min) and SBF, (44.7+/-3.2 to 29.1+/-5.3 mL/min), and an increase in Dt-apCO2 (2+/-2.8 to 20.5+/-4.5 mm Hg). No alterations on systemic metabolic or O2-derived variables were observed. The increase of the Dt-apCO2 correlated with the grade of mucosal injury.

CONCLUSION

IHP induces a proportional reduction on blood flow in all layers of the intestine, and none of the systemic markers of splanchnic ischemia predict the intestinal blood flow disturbances during the early phase of intestinal transplantation. In addition, intestinal pCO2 measurement seems to be a useful way for monitoring graft perfusion and histological changes after hypothermic ischemia and reperfusion.

2003 report of the intestine transplant registry: a new era has dawned

SUMMARY BACKGROUND DATA

The intestine has been more difficult to transplant than other solid organs. We analyzed registry data to determine the scope and success of intestine transplantation in the current era.

METHODS

All known intestinal-transplant programs participated. Patient- and graft-survival estimates were obtained using the Kaplan-Meier product limit method and were analyzed with the Wilcoxon statistic.

RESULTS

Sixty-one programs provided data on 989 grafts in 923 patients. Four patients were lost to follow-up. The short-gut syndrome was the most common primary indication for transplantation. Sixty-one percent of the recipients were < or =18 years. Proportionally more combined intestinal and liver transplants were performed in this group. More than 80% of all current survivors had stopped parenteral nutrition and resumed normal daily activities. A multivariate analysis of cases within the last 5 years revealed that transplantation of patients waiting at home, recipient age, antibody induction immune suppression, and center experience with at least 10 cases were associated with improved patient survival. One-year graft survival rates of 81% were achieved in patients who were induced with antithymocyte globulin and maintained on tacrolimus.

CONCLUSIONS

Transplantation is an effective therapy for the treatment of patients with end-stage intestine failure who cannot tolerate parenteral nutrition. With newer immune suppressive protocols, 1-year graft and patient survival rates approach the results of liver transplantation. Further improvement in survival are expected with early referral since suitable donor organs are scarce and survival rates are better when patients are well enough to wait at home for their transplant.

Is there a role for living donor intestine transplants?

The use of living donors with intestinal transplantation is controversial because it may not significantly improve candidate access to organs when intestine-only grafts are needed, and may involve excessive donor risk when combined liver-intestine grafts are required. Although limited data are available for comparison at this time, graft and patient survival rates for intestinal transplantations using living donors are no different than for deceased donor transplantations. Potential benefits that may be provided to the intestine transplant recipient through the use of living donors include better HLA matching, shorter ischemia times, better bowel preparation, and better opportunities for introducing immunomodulatory strategies. Conversely, living intestine donors are at risk for mortality, significant morbidity, financial loss, and psychologic trauma. The long-term outcomes of living intestine donors have not yet been reported. Ultimately, these data are essential before the wider use of living donors can be advocated for intestinal transplantation.

Efeitos hemodinâmicos e metabólicos iniciais da perfusão hipotérmica intestinal in situ.: avaliação de um novo modelo canino de autotransplante intestinal

O transplante intestinal tem sido utilizado como uma alternativa promissora no tratamento da síndrome do intestino curto em pacientes adultos e pediátricos. Vários modelos experimentais foram desenvolvidos com a finalidade de testar diferentes soluções de preservação. No entanto são modelos complexos que levam, muitas vezes, um tempo prolongado para a sua realização. OBJETIVO: Neste estudo, desenvolvemos um modelo alternativo de autotransplante intestinal in situ analisando os efeitos hemodinâmicos e metabólicos iniciais da perfusão hipotérmica com solução de Ringer lactato. MÉTODOS: Foram utilizados seis cães machos sem raça definida (22,8±1,4 Kg); as variáveis hemodinâmicas sistêmicas foram obtidas por meio de cateter arterial e pelo Swan-Ganz. A perfusão do trato gastrintestinal foi avaliada pela medida do fluxo sangüíneo da veia mesentérica superior (FSVMS, fluxômetro ultra-sônico), e através da medida do pCO2 intestinal (pCO2-int e pCO2-gap, tonometria a gás). Inicialmente realizamos a secção do jejuno proximal e íleo distal e isolamento dos vasos mesentéricos com fitas cardíacas, todo o tecido nervoso e linfático em torno do eixo vascular intestinal foi seccionado. O território mesentérico foi perfundido através da artéria mesentérica superior por 30 minutos com 1000 ml de Ringer lactato a 4ºC, e o efluente drenado através de uma pequena incisão na veia mesentérica superior. Os animais foram observados por 120 min após o inicio do período de reperfusão. Amostras de sangue foram obtidas da aorta abdominal, para análise gasométrica. RESULTADOS: A perfusão intestinal hipotérmica induziu uma redução do FSMVS apenas nos primeiros 30 min de reperfusão (587±70,9 para 398±102,8 ml/min) e um aumento do pCO2-gap (2±2,7 para 29,8±6 mmHg). Não foram observadas alterações significativas em relação a parâmetros hemodinâmicos e metabólicos sistêmicos (PAM, DC, pH, excesso de bases, hemoglobina) assim como na temperatura central. CONCLUSÃO: O modelo de autotransplante intestinal é extremamente útil e de fácil execução, para a avaliação inicial de soluções de preservação e/ou drogas antioxidantes, comumente utilizadas no transplante de intestino.

Gut failure and abdominal visceral transplantation

Despite the reported high survival with total parenteral nutrition (TPN) therapy for patients with intestinal failure, a considerable number of patients do not escape the potential risks of TPN-associated complications, including hepatic failure, vanishing of central venous access and line sepsis. Thus, intestinal, liver-intestinal and multivisceral transplantation have recently emerged to rescue those who can no longer be maintained on TPN. Before this development, and for nearly three decades, small-bowel transplantation was plagued with uncontrolled rejection, graft v. host disease and fatal infection. These barriers stemmed from the large gut lymphoid mass and heavy microbial load contained in the intestinal lumen. The recent improvement in survival after the clinical introduction of tacrolimus with achievement of full enteric nutritional autonomy qualified the procedure by the US Health Care Financing Administration as the standard of care for patients with intestinal and TPN failure. The decision was supported by a decade of clinical experience with cumulative improvement in patient and graft survival. In addition, the introduction of new effective immunoprophylactic agents and novel therapeutic approaches has contributed to a further increase in the therapeutic advantages of the procedure. The present review article outlines the current clinical practice of intestinal transplantation and defines new management strategies with the aim of raising the level of the procedure to be a better alternative therapy for TPN-dependent patients.

Natural history of intestinal failure, investigated through a national network-based approach

OBJECTIVES

Intestinal failure (IF) is a condition whose treatment requires advanced knowledge and techniques and a multidisciplinary approach. Intestinal failure is the endpoint of many intestinal diseases and may result in full recovery, in life-long parenteral nutrition, or in the death of the child. The aim of this study was to evaluate the natural history of IF in children using a national network of resources.

METHODS

Italian centers of pediatric gastroenterology merged in a national network, developing a collaborative management approach for children with IF. A consensus definition of IF was achieved. A database was set up to investigate the cause, epidemiologic factors, and natural history of IF.

RESULTS

One hundred nine children were enrolled in 5 years. The cause of IF was: short bowel syndrome (n = 48), disorders of motility (n = 16), structural enterocyte defects (n = 14), multiple food intolerance (n = 10), autoimmune enteropathy (n = 7), and others or unknown (n = 14). The eventual outcome was closely related to the primary cause, ranging from full and permanent intestinal sufficiency in children with multiple food intolerance to high death rate or total dependance upon parenteral nutrition in those with structural enterocyte defects. Intermediate outcomes were observed for the other causes. Four children received intestinal transplantation.

CONCLUSIONS

The network approach for IF provides an effective model to optimize resources and to investigate prospectively the natural history of IF. Based on the work on this series, a European network for IF could be an effective model for fulfilling the diagnostic and management needs, including intestinal transplantation.

Transplante de intestino delgado

RACIONAL: Avanços da biotecnologia e o desenvolvimento de novas drogas imunossupressoras melhoraram os resultados do transplante de intestino delgado. Esse transplante é atualmente indicado para casos especiais da falência intestinal. OBJETIVO: A presente revisão realça os recentes desenvolvimentos na área do transplante de intestino delgado. MATERIAL E MÉTODO: Mais de 600 publicações de transplante de intestino delgado foram revisadas. O desenvolvimento da pesquisa, novas estratégias de imunossupressão, monitorização do enxerto e do receptor, e avanços na técnica cirúrgica são discutidos. RESULTADOS: Realizaram-se cerca de 700 transplante de intestino delgado em 55 centros: 44% intestino-fígado, 41% enxerto intestinal isolado e 15% transplante multivisceral. Rejeição e infecção são as principais limitações desse transplante. Sobrevida de 5 anos na experiência internacional é de 46% para o transplante de intestino isolado, 43% para o intestino-fígado e de cerca de 30% para o transplante multivisceral. Sobrevidas prolongadas são mais freqüentes nos centros com maior experiência. Em série de 165 transplantes intestinais na Universidade de Pittsburgh, PA, EUA, foi relatada sobrevida do paciente maior do que 75% no primeiro ano, 54% em 5 anos e 42% em 10 anos. Mais de 90% desses pacientes assumem dieta oral irrestrita. CONCLUSÃO: O transplante de intestino delgado evoluiu de estratégia experimental para uma alternativa viável no tratamento da falência intestinal permanente. Promover o refinamento da terapia imunossupressora, do manejo e prevenção de infecções, da técnica cirúrgica e da indicação e seleção adequada dos pacientes é crucial para melhorar a sobrevida desse transplante.

Small bowel transplant: an evidence-based analysis

OBJECTIVE

The Medical Advisory Secretariat undertook a review of the evidence on the effectiveness and cost-effectiveness of small bowel transplant in the treatment of intestinal failure.

SMALL BOWEL TRANSPLANTATION

Intestinal failure is the loss of absorptive capacity of the small intestine that results in an inability to meet the nutrient and fluid requirements of the body via the enteral route. Patients with intestinal failure usually receive nutrients intravenously, a procedure known as parenteral nutrition. However, long-term parenteral nutrition is associated with complications including liver failure and loss of venous access due to recurrent infections. Small bowel transplant is the transplantation of a cadaveric intestinal allograft for the purpose of restoring intestinal function in patients with irreversible intestinal failure. The transplant may involve the small intestine alone (isolated small bowel ISB), the small intestine and the liver (SB-L) when there is irreversible liver failure, or multiple organs including the small bowel (multivisceral MV or cluster). Although living related donor transplant is being investigated at a limited number of centres, cadaveric donors have been used in most small bowel transplants. The actual transplant procedure takes approximately 12-18 hours. After intestinal transplant, the patient is generally placed on prophylactic antibiotic medication and immunosuppressive regimen that, in the majority of cases, would include tacrolimus, corticosteroids and an induction agent. Close monitoring for infection and rejection are essential for early treatment.

MEDICAL ADVISORY SECRETARIAT REVIEW

The Medical Advisory Secretariat undertook a review of 35 reports from 9 case series and 1 international registry. Sample size of the individual studies ranged from 9 to 155. As of May 2001, 651 patients had received small bowel transplant procedures worldwide. According to information from the Canadian Organ Replacement Register, a total of 27 small bowel transplants were performed in Canada from 1988 to 2002.

PATIENT OUTCOMES

The experience in small bowel transplant is still limited. International data showed that during the last decade, patient survival and graft survival rates from SBT have improved, mainly because of improved immunosuppression therapy and earlier detection and treatment of infection and rejection. The Intestinal Transplant Registry reported 1-year actuarial patient survival rates of 69% for isolated small bowel transplant, 66% for small bowel-liver transplant, and 63% for multivisceral transplant, and a graft survival rate of 55% for ISB and 63% for SB-L and MV. The range of 1-year patient survival rates reported ranged from 33%-87%. Reported 1-year graft survival rates ranged from 46-71%. Regression analysis performed by the International Transplant Registry in 1997 indicated that centres that have performed at least 10 small bowel transplants had better patient and graft survival rates than centres that performed less than 10 transplants. However, analysis of the data up to May 2001 suggests that the critical mass of 10 transplants no longer holds true for transplants after 1995, and that good results can be achieved at any multiorgan transplant program with moderate patient volumes. The largest Centre reported an overall 1-year patient and graft survival rate of 72% and 64% respectively, and 5-year patient and graft survival of 48% and 40% respectively. The overall 1-year patient survival rate reported for Ontario pediatric small bowel transplants was 61% with the highest survival rate of 83% for ISB. The majority (70% or higher) of surviving small bowel transplant recipients was able to wean from parenteral nutrition and meet all caloric needs enterally. Some may need enteral or parenteral supplementation during periods of illness. Growth and weight gain in children after ISB were reported by two studies while two other studies reported a decrease in growth velocity with no catch-up growth. The quality of life after SBT was reported to be comparable to that of patients on home enteral nutrition. A study found that while the parents of pediatric SBT recipients reported significant limitations in the physical and psychological well being of the children compared with normal school children, the pediatric SBT recipients themselves reported a quality of life similar to other school children. Survival was found to be better in transplants performed since 1991. Patient survival was associated with the type of organ transplanted with better survival in isolated small bowel recipients.

ADVERSE EVENTS

Despite improvement in patient and graft survival rates, small bowel transplant is still associated with significant mortality and morbidity. Infection with subsequent sepsis is the leading cause of death (51.3%). Bacterial, fungal and viral infections have all been reported. The most common viral infections are cytomegalorvirus (18-40%) and Epstein-Barr virus. The latter often led to ß-cell post-transplant lymphoproliferative disease. Graft rejection is the second leading cause of death after SBT (10.4%) and is responsible for 57% of graft removal. Acute rejection rates ranged from 51% to 83% in the major programs. Most of the acute rejection episodes were mild and responded to steroids and OKT3. Antilymphocyte therapy was needed in up to 27% of patients. Isolated small bowel allograft and positive lymphocytotoxic cross-match were found to be risk factors for acute rejection. Post-transplant lymphoproliferative disease occurred in 21% of SBT recipients and accounted for 7% of post-transplant mortality. The frequency was higher in pediatric recipients (31%) and in adults receiving composite visceral allografts (25%). The allograft itself is often involved in post-transplant lymphoproliferative disease. The reported incidence of host versus graft disease varied widely among centers (0% - 14%). Surgical complications were reported to occur in 85% of SB-L transplants and 25% of ISB transplants. Reoperations were required in 45% - 66% of patients in a large series and the most common reason for reoperation was intra-abdominal abscess. The median cost of intestinal transplant in the US was reported to be approximately $275,000US (approximately CDN$429,000) per case. A US study concluded that based on the US cost of home parenteral nutrition, small bowel transplant could be cost-effective by the second year after the transplant.

CONCLUSION

There is evidence that small bowel transplant can prolong the life of some patients with irreversible intestinal failure who can no longer continue to be managed by parenteral nutrition therapy. Both patient survival and graft survival rates have improved with time. However, small bowel transplant is still associated with significant mortality and morbidity. The outcomes are inferior to those of total parenteral nutrition. Evidence suggests that this procedure should only be used when total parenteral nutrition is no longer feasible.

Small bowel extrinsic denervation does not alter water and electrolyte absorption from the colon in the fasting or early postprandial state

Small bowel transplantation (SBT) causes watery diarrhea. The decreases shown previously in absorption of water, electrolytes, and bile salts in the jejunum and ileum, although present, are not dramatic and seem not to be great enough to explain the diarrhea. Our aim was to determine changes in water and electrolyte absorption in the colon during fasting and postprandially in a canine preparation of jejunoileal extrinsic denervation, which serves as a model of jejunoileal autotransplantation. We hypothesized that colonic absorption of water and electrolytes decreases transiently in the colon after SBT. Six dogs had cannulas implanted in the colon to study absorption of an ileal-like basal electrolyte solution with or without 10 mmol/L glucose. Absorption during fasting and postprandially was measured before and 2 and 12 weeks after a validated preparation of jejunoileal extrinsic denervation. All dogs developed diarrhea after SBT. Net colonic absorptive fluxes of water and electrolytes in the colon did not change from baseline values at 2 or 12 weeks after extrinsic denervation, either during fasting or postprandially; glucose in the infusate did not alter absorptive fluxes during fasting or postprandially. Extrinsic denervation of the small intestine does not appear to alter colonic absorption of water or electrolytes during fasting or postprandially. These observations suggest that the neurally intact colon has a minimal role in the diarrhea after SBT.

Late graft loss and long-term outcome after isolated intestinal transplantation in children

BACKGROUND/PURPOSE

The aim of this study was to determine causes of late graft loss and long-term outcome after isolated intestinal transplantation in children at a single center.

METHODS

All children who underwent primary isolated intestinal transplantation at our center with a minimum follow-up of 1 year were the subject of this retrospective study.

RESULTS

Twenty-eight children underwent primary isolated intestinal transplantation. Median graft survival was 705 days (range, 0 to 2,630 days) and median patient survival was 1,006 days (range, 0 to 2,630 days). There were 6 deaths and 15 graft losses (including the 6 nonsurvivors). Seven of the losses occurred 6 or more months after transplant. Of these, 2 losses occurred because of death of the recipients of sepsis; both recipients had functioning grafts. The 5 remaining late graft losses occurred because of acute rejection in 2 patients, chronic rejection in 2 (1 with concomitant acute rejection) and a diffuse stricturing process without the histologic hallmarks of chronic rejection in the fifth. All late survivors with intact grafts are off total parenteral nutrition (TPN).

CONCLUSIONS

Late graft loss remains a concern in a small percentage of patients after isolated intestinal transplantation. Nutritional autonomy from TPN is possible in the majority of these children after transplantation.

Recent advances and future prospects in intestinal and multi-visceral transplantation

From an experimental procedure, intestinal transplantation (ITx) has evolved over the last 10 yr into a treatment option for patients suffering from short bowel syndrome and who develop life-threatening complications from total parenteral nutrition (TPN) (e.g. liver dysfunction, line sepsis, shortage of venous access, etc.). One-year survival rates are approximately 70% and thus similar to lung Tx. However, the intestine remains the most challenging abdominal organ to transplant. This is because of the severe immune response (mostly rejection) that is produced, and therefore the need for profound immunosuppression with its attendant complications (sepsis, lymphoma, direct drug toxicity). Unlike other organs, graft loss as a result of acute rejection can occur late after transplantation (more than 1 yr post-transplant). With regard to the actual immunosuppressive regimens, considerable experience in patient management is required to optimize outcome of those complex transplants, which are permanently at risk of rejection and infection. ITx remains an unfinished product, and the application of ITx to patients doing well on TPN warrants further research in the understanding of the rejection process, in the development of less toxic and more efficient immunosuppressive protocols, and in the development of immunomodulatory strategies, to better control rejection and thereby reduce the need for immunosuppression.

Small bowel transplantation

Small bowel transplantation has become the treatment of choice for patients with chronic gut failure whose illness cannot be maintained on home parenteral nutrition. Outcomes have improved as a result of refinements in patient selection, surgical techniques, and the prevention, diagnosis, and treatment of graft rejection. Early listing is important because of the shortage of organ donors. Rejection rates are still 50% or more, despite the use of potent immune suppression. Sepsis rates are also higher for patients who have had small bowel transplantation than for those who have received other organs because of bacterial translocation from the gut secondary to preservation injury and graft rejection. Graft and patient survival rates after small bowel transplantation are comparable to rates after lung transplantation. Successful transplant recipients resume unrestricted oral diets.

Clinical intestinal transplantation: a decade of experience at a single center

OBJECTIVE

To assess the long-term efficacy of intestinal transplantation under tacrolimus-based immunosuppression and the therapeutic benefit of newly developed adjunct immunosuppressants and management strategies.

SUMMARY BACKGROUND DATA

With the advent of tacrolimus in 1990, transplantation of the intestine began to emerge as therapy for intestinal failure. However, a high risk of rejection, with the consequent need for acute and chronic high-dose immunosuppression, has inhibited its widespread application.

METHODS

During an 11-year period, divided into two segments by a 1-year moratorium in 1994, 155 patients received 165 intestinal allografts under immunosuppression based on tacrolimus and prednisone: 65 intestine alone, 75 liver and intestine, and 25 multivisceral. For the transplantations since the moratorium (n = 99), an adjunct immunosuppressant (cyclophosphamide or daclizumab) was used for 74 transplantations, adjunct donor bone marrow was given in 39, and the intestine of 11 allografts was irradiated with a single dose of 750 cGy.

RESULTS

The actuarial survival rate for the total population was 75% at 1 year, 54% at 5 years, and 42% at 10 years. Recipients of liver plus intestine had the best long-term prognosis and the lowest risk of graft loss from rejection (P =.001). Since 1994, survival rates have improved. Techniques for early detection of Epstein-Barr and cytomegaloviral infections, bone marrow augmentation, the adjunct use of the interleukin-2 antagonist daclizumab, and most recently allograft irradiation may have contributed to the better results.

CONCLUSION

The survival rates after intestinal transplantation have cumulatively improved during the past decade. With the management strategies currently under evaluation, intestinal transplant procedures have the potential to become the standard of care for patients with end-stage intestinal failure.

Bacterial translocation in clinical intestinal transplantation

BACKGROUND

Bacterial translocation (BT) has been suggested to be responsible for the high incidence of infections occurring after small bowel transplantation (SBTx). Bacterial overgrowth, alteration of the mucosal barrier function 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 immunosuppression were analyzed. Blood, stool, and liver biopsies and peritoneal fluid were cultured (circa 4000 total specimens) when infection was clinically suspected or as part of follow-up. BT episodes were considered when microorganisms were found simultaneously in blood or liver biopsy and stool.

RESULTS

BT (average of 2.0 episodes/patient) was evident in 44% of patients and was most frequently caused by Enterococcus, Staphylococcus, Enterobacter, and Klebsiella. The presence of a colon allograft was associated with a higher rate of BT (75% vs. 33.3%). Furthermore, the transplantation procedure (colon vs. no colon) affected the rate of BT: SBTx=40% vs. 25%, combined 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 cases. In 5.2% of the cases, positive blood cultures without stool confirmation of the bacteria were seen. Prolonged cold ischemia time (CIT) affected BT rate significantly (CIT>9 hr 76% vs. CIT<9 hr 20.8%).

CONCLUSIONS

This study shows that 1) a substantial percentage of, but not all, BT is associated with AR, 2) the presence of a colon allograft increases the risk for BT, and 3) a long CIT is associated with a high incidence of BT after SBTx.

Segmental living related small bowel transplantation in adults

The advent of small bowel transplantation has provided selected patients with chronic intestinal irreversible failure with a physiologic alternative to total parenteral nutrition. Recently a standardized technique for living related small bowel transplantation (LR-SBTx) has been developed. Three patients with short bowel syndrome underwent LR-SBTx at our institution. All donors were ABO compatible with a good human leukocyte antigen match. A segment of 180 to 200 cm of ileum was harvested and transplanted with its vascular pedicle constituted by the ileocolic artery and vein. The grafts were transplanted with a short cold and warm ischemia time. The immunosuppression regimen consisted of oral FK-506, prednisone, and intravenous induction with atgam. Serial biopsies of the intestinal grafts were performed to evaluate rejection or viral infections. The postoperative course was uneventful for all donors. All of the recipients are currently alive and well. Two of three patients are off total parenteral nutrition and tolerating an oral diet with no limitations on daily activity. In the third patient, the graft was removed 6 weeks after transplantation. At the time of enterectomy, no technical or immunologic complications were documented. Absorption tests for D-xylose and fecal fat studies were performed showing functional adaptation of the segmental graft. All biopsies were negative for acute rejection. A well-matched segmental ileal graft from a living donor can provide complete rehabilitation for patients with short bowel syndrome. Our initial experience suggests that the risk of acute rejection and infection is greatly reduced compared to cadaveric bowel transplantation. Further clinical application of this procedure is warranted.