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The last three decades witnessed continual evolution of the organ allocation strategy. The Organ Procurement and Transplant Network (OPTN) primary goals were to promote patient access to transplantation and improve equity among single and multi-organ candidates. Other intended objectives were to optimize donor use and maximize transplant utility. These relentless efforts were commanded by the OPTN 'Final Rule' and directed by different scientific and legislative allied committees (1).

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.

Purpose of review Despite three decades of clinical experience, this article is the first to comprehensively address disease recurrence after gut transplantation. Pertinent scientific literature is reviewed and management strategies are discussed with new insights into advances in gut pathobiology and human genetics. Recent findings With growing experience and new perspectives in the field of gut transplantation, the topic of disease recurrence continues to evolve. The clinicopathologic spectrum and diagnostic criteria are better defined in milieu of the nature of the primary disease. In addition to neoplastic disorders, disease recurrence is suspected in patients with pretransplant Crohn's disease, gut dysmotility, hypercoagulability and metabolic syndrome. There has also been an increased awareness of the potential de-novo development of various disorders in the transplanted organs. For conventionally unresectable gastrointestinal and abdominal malignancies, ex-vivo excision and autotransplantation are advocated, particularly for the nonallotransplant candidates. Summary Similar to other solid organ and cell transplantations, disease recurrence has been suspected following gut transplantation. Despite current lack of conclusive diagnostic criteria, recurrence of certain mucosal and neuromuscular disorders has been recently described in a large single-centre series with an overall incidence of 7%. Disease recurrence was also observed in recipients with pretransplant hypercoagulability and morbid obesity with respective incidences of 4 and 24%. As expected, tumour recurrence is largely determined by type, extent and biologic behaviour of the primary neoplasm. With the exception of high-grade aggressive malignancy, disease recurrence is still of academic interest with no significant impact on overall short and long-term outcome.

Intestinal transplantation has evolved from its experimental origins in the mid-20th century to its status today as an established treatment option for patients with end-stage intestinal failure who cannot be sustained with total parenteral nutrition. The most common source of intestinal failure in both adults and children is short-bowel syndrome, but a host of other disease processes can lead to this common end-point. The development of intestinal transplantation has presented multiple hurdles for the transplant community, including technical challenges, immunologic pitfalls, and infectious complications. Despite these hurdles, the success rate has climbed over the past decades owing to achievements that include improved surgical techniques, new immunosuppressive regimens, and more effective strategies for posttransplant surveillance and management. Nearly 2800 intestinal transplants have been performed worldwide, and current patient and graft survival rates are now comparable to those of other types of solid organ transplantations. As their population continues to increase, it will be increasingly likely that intestinal-transplant patients will seek imaging at sites other than transplant centers. Therefore, it is important that diagnostic and interventional radiologists be familiar with the procedure, its common variations, and the spectrum of postoperative complications. In this article, the authors provide an overview of intestinal transplantation, including the indications, variations, expected postoperative anatomy, and range of potential complications.

Small bowel transplant is an acceptable procedure for intractable Crohn’s disease (CD). Some case reports and small series describe the apparent recurrence of CD in the transplanted bowel. This commentary discusses evidence in favor of and against this alleged recurrence and argues that a molecular characterization is needed to prove or disprove that inflammation emerging in the transplanted bowel is a true recurrence of the original CD.

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.

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 successful development of multivisceral and composite visceral transplantation is among the milestones in the recent history of human organ transplantation. All types of gastrointestinal transplantation have evolved to be the standard of care for patients with gut failure and complex abdominal pathologic conditions. The outcome has markedly improved over the last 3 decades owing to technical innovation, novel immunosuppression, and better postoperative care. Recent data documented significant improvement in the long-term therapeutic indices of all types of visceral transplantation close to that achieved with thoracic and solid abdominal organs.

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.

BACKGROUND Fusarium spp. infections have become an emerging and lethal threat to the immunocompromised patient population, especially those with neutropenia. Recently there have been increased reports in solid organ transplant recipients. Presentation is commonly as soft tissue infections several months post-transplant. With high morbidity and mortality, efficacious antifungal therapy is essential. This remains challenging with limited data and no established clinical breakpoints defined. CASE REPORT We report on a modified multi-visceral transplant patient that developed a Fusarium infection only 7 weeks post-transplant in the native hard palate and esophagus, without any soft tissue lesions, which persisted despite aggressive combination treatment with amphotericin B lipid complex and voriconazole. CONCLUSIONS Fusarium spp. infection in solid organ transplant is a significant challenge without clear diagnostic clinical indicators of infection, or specific time of onset, in addition to possible emergence of a more aggressive drug-resistant strain.

Recent advances in immunosuppressive regimens have decreased acute cellular rejection (ACR) rates and improved intestinal transplant (ITx) recipient survival. We investigated the role of myeloid-derived suppressor cells (MDSCs) in ITx. We identified MDSCs as CD33(+)CD11b(+)lineage(CD3/CD56/CD19)(−)HLA-DR(−/low) cells with 3 subsets, CD14(−)CD15(−) (e-MDSC), CD14(+)CD15(−) (M-MDSC), and CD14(−)CD15(+) (PMN-MDSC), in peripheral blood mononuclear cells (PBMCs) and mononuclear cells in the grafted intestinal mucosa. Total MDSC numbers increased in PBMCs following ITx; among MDSC subsets, M-MDSC numbers were maintained at high level after 2 months following ITx. The MDSC numbers decreased in ITx recipients suffering from ACR. MDSC numbers were positively correlated with serum IL-6 levels and the glucocorticoid administration index. IL-6 and methylprednisolone enhanced the differentiation of bone marrow cells (BMCs) to MDSCs in vitro. M-MDSCs and e-MDSCs expressed CCR1, -2, and -3, e-MDSCs and PMN-MDSCs expressed CXCR2, and intestinal grafts expressed the corresponding chemokine ligands following ITx. Of note, the percentage of MDSCs among intestinal mucosal CD45(+) cells increased after ITx. A novel in vitro assay demonstrated that MDSCs suppressed donor-reactive T-cell-mediated destruction of donor intestinal epithelial organoids. Taken together, our results suggest that MDSCs accumulate in the recipient PBMCs and the grafted intestinal mucosa in ITx, and may regulate ACR.

Normothermic machine perfusion (NMP) is an emerging technology to preserve liver allografts more effectively than cold storage (CS). However, little is known about the effect of NMP on steatosis and the markers indicative of hepatic quality during NMP. To address these points, we perfused 10 discarded human livers with oxygenated NMP for 24 hours after 4-6 hours of CS. All livers had a variable degree of steatosis at baseline. The perfusate consisted of packed red blood cells and fresh frozen plasma. Perfusate analysis showed an increase in triglyceride levels from the 1st hour (median, 127 mg/dL; interquartile range [IQR], 95-149 mg/dL) to 24th hour of perfusion (median, 203 mg/dL; IQR, 171-304 mg/dL; P = 0.004), but tissue steatosis did not decrease. Five livers produced a significant amount of bile (≥5 mL/hour) consistently throughout 24 hours of NMP. Lactate in the perfusate cleared to3 mmol/L in most livers within 4-8 hours of NMP, which was independent of bile production rate. This is the first study to characterize the lipid profile and functional assessment of discarded human livers at 24 hours of NMP. Liver Transplantation 24 233-245 2018 AASLD.

Small bowel transplantation is a surgical technique reserved for patients with end-stage intestinal failure. Despite its inherent technical difficulties, it has emerged as the standard of care for these patients. This article reviews the background and different surgical techniques for this procedure and then fully describes the spectrum of imaging findings of pancreatic and biliary complications, which have a prevalence of up to 17%, after this procedure based on 23-year single-center experience. The pancreaticobiliary complications encountered in our experience and discussed in this article include: ampullary stenosis, biliary cast, choledocholithiasis, bile leak, recurrent cholangitis, acute pancreatitis, chronic pancreatitis, and pancreatic duct fistula. Familiarity with the broad spectrum of PB complications and their variable manifestations will help radiologists to accurately diagnose these complications which have relatively high morbidity and mortality in these immune-compromised patients.

BACKGROUND Multivisceral transplantation has recently evolved to be a life-saving procedure for patients with intestinal failure and complex abdominal pathology. A composite aortic graft is always needed to restore the arterial flow to the transplanted organs. Accordingly, arterial complications can be life-threatening requiring prompt intervention. Herein, we describe innovative technical approaches in seven recipients who developed pseudo-aneurysm (PA) after transplantation. METHODS With a total of 285 composite visceral transplants, 15 (5.2%) patients experienced vascular complications. Of these, 7 were life-threatening PAs that were diagnosed 61 to 2677 days after transplantation. Due to the anatomic and technical complexity of the allograft vasculature, endovascular techniques were introduced alone (n=2) or in conjunction with surgical intervention (n=5) in an attempt to rescue patients and salvage the transplanted organs. RESULTS The endovascular and surgical technical approaches used for each of the 7 PA actively bleeding patients was successful in 5 (71%). Of these, 2 (40%) are alive 86 to 117 months after the intervention. The remaining 5 recipients died of recurrent hemorrhage (n=2), liver failure (n=1), and pneumonia (n=1). The cause of death was unknown in the remaining patient. Retransplantation and intra-abdominal infections were major risk factors. Candida was the most common isolated microorganism. CONCLUSIONS Recipients of composite visceral allografts are at risk of developing life-threatening PAs, particularly in those with early posttransplantation abdominal infections. Prompt multidisciplinary diagnosis and therapeutic approaches are crucial management strategies.

Encapsulating peritoneal sclerosis (EPS) is a rare but devastating complication of peritoneal dialysis characterized by fibrosis and calcification of the intestine that, in severe cases, can progress to intestinal failure and total parenteral nutrition dependency. Medical and surgical interventions carry a poor prognosis in these patients. We describe a case of a 36-year-old female with end-stage kidney disease and severe EPS not amenable to surgical intervention who underwent a combined intestinal and kidney transplantation. At 3 years posttransplantation, the patient has normal intestinal and kidney function. This represents, to our knowledge, the first report of severe EPS and end-stage kidney disease treated with a combined transplant.

The improvement of outcomes in intestinal transplantation (ITx) over the last two decades has been made possible through standardization in surgical techniques, improvements in immunosuppressive and induction protocols, and post-operative patient care. From a surgical technical point of view, all different types of small bowel containing transplants can be categorized into three main prototypes, including isolated small bowel, liver-small bowel, and multivisceral transplantations. In this review, we describe these three main prototypes and discuss the most important technical modifications of each type, as well as donor and recipient procedures, and highlight the more recent operative technical topics of discussion in the literature.

Venous access is crucial in intestinal transplantation, but a thrombosed venous system may prevent the use of central veins of the upper body. The incidence of venous thrombosis and the necessity to perform alternative vascular access (AVA) in intestinal transplant recipients have not been fully investigated.Records of adult patients who underwent intestinal transplantation between January 1, 2001, and December 31, 2009, were reviewed. Contrast venography was performed as pre-transplantation screening. Vascular accesses at the transplantation were categorized as I (percutaneous line via the upper body veins), II (percutaneous line via the lower body veins), and III (vascular accesses secured surgically, with interventional radiology, or using non-venous sites). Categories II and III were defined as AVA. Risk factors for central venous thrombosis and those for requiring AVA were analysed, respectively.Among 173 patients, central venous obstruction or stenosis (50% of normal diameter) was found in 82% (141 patients). AVA was required in 4.6% (eight patients: four in each category II and III). Large-bore infusion lines were placed via the femoral arteries in all category III patients without complications. Existing inferior vena cava filter and hypercoagulable states were identified as the risk factors for the use of AVA, but not for central venous thrombosis. Outcomes of patients who underwent AVA were similar to those of patients without AVA.The majority of adult patients undergoing intestinal transplantation had at least one central venous stenosis or obstruction. The recipient outcomes were comparable when either standard vascular access or AVA was used for transplantation.

Background. Liver-sparing "modified" multivisceral transplantation (MMVTx) has recently been more used for patients with diffuse gastrointestinal disorders and preserved hepatic functions. Evisceration techniques with preservation of native spleen were also introduced to reduce risk of posttransplant lymphoproliferative disorders. This study focuses on the indications of MMVTx for patients with familial adenomatous polyposis (FAP) and the technical feasibility of performing spleen-preserving pancreaticoduodenectomy (SPPD). Methods. Between 1993 and 2009, 10 FAP patients required MMVTx. Nine were adults and one was a child, with a female:male ratio of 1:1. Results. Short gut with duodenal adenomatosis and extensive desmoid tumors with pancreaticoduodenal involvement dictated need for MMVTx. SPPD was technically feasible in four recipients, and conventional evisceration including splenectomy was performed in remaining six recipients. With an overall cumulative survival of 90% at 1 year and 77% at 10 years, all SPPD recipients were alive with no single example of posttransplant lymphoproliferative disorder, graft-versus-host disease, or chronic rejection. However, SPPD was associated with an increase (P>0.3) in total ischemia time, operative time, and packed red blood cells requirement but with shorter (P=0.6) length of hospital stay. With a mean follow-up of 50±45 months (range 18-128 months), none of the 10 recipients experienced intraabdominal desmoid tumor recurrence or developed de novo visceral allograft neoplasm. Conclusion. MMVTx is a valuable therapeutic option for FAP patients who are in need for visceral transplantation with pathologic involvement of the pancreaticoduodenal complex. SPPD is technically feasible, and efforts should always be made to preserve native spleen because of the reported herein therapeutic advantages. Keywords: Modified multivisceral transplantation, Intestinal transplant, Familial adenomatous polyposis, Gardner's syndrome, Desmoid tumors.

Rotavirus enteritis (RVE) is increasingly recognized as a cause of small bowel allograft dysfunction but its significance in adult patients is unknown. We have studied 23 adult small bowel transplant patients aged 19.8-59 years (mean = 38.2 years), who were presented with diarrhea and tested positive for rotavirus by enzyme-linked immunosorbent assay methods. Serial follow-up biopsies, as well as clinical data, are documented and analyzed. These patients were followed up for an average of 168 days (range 33-534 days). Mean time of rotavirus diagnosis from transplant day was 794 days (range 38-2907 days). Self-limited diarrhea lasting 6-13 days (mean = 9 days) was the main presentation. Sixteen (69.6%) patients developed acute cellular rejection either concurrently with (i.e. six patients) or after (10 patients) RVE, often characterized by prominent mucosal plasmacytosis at an average of 22 days (range 0-94 days) from the day RVE was diagnosed. One-third of patients with acute rejection (i.e. five out of 16) required muromonab-CD3 rescue therapy. Two patients experienced graft loss (one from chronic rejection, another from sepsis). Rotavirus infection is a cause of diarrhea in adult small bowel transplant patients. The infection appeared to trigger cellular rejection that was associated with mucosal plasmacytosis, and sometimes required aggressive rescue therapy.

Over the last 3 decades, management of acute variceal bleeding and measures to prevent recurrent episodes has evolved due to the introduction of new therapeutic modalities including innovative surgical and minimally invasive shunt procedures. Such an evolution has been compounded by the parallel progress that has been achieved in organ transplantation. This article focuses primarily on the commonly used surgical and radiologic shunt procedures. Liver and multivisceral transplantation are also briefly discussed as important parts of the algorithmic management of these complex patients, particularly those with hepatic decompensation and portomesenteric venous thrombosis.

This report describes a new innovative pull-through technique of hindgut reconstruction with en bloc small bowel and colon transplantation in a Crohn's disease patient with irreversible intestinal failure. The approach was intersphincteric and the anastomosis was established between the allograft colon and the recipient anal verge with achievement of full nutritional autonomy and anal continence.

Background More than 60% children with small bowel transplantation (SBTx) experience acute cellular rejection. Purpose/methods To identify children at risk of rejection, donor- and third-party-induced proliferation of T-helper and T cytotoxic (Tc) cells, and their naive and memory (M) subsets was evaluated simultaneously in single blood samples from 28 children who received SBTx after induction with rabbit anti-human thymocyte globulin. Proliferation was measured by dilution of the intravital dye carboxyfluorescein succinimidyl ester (CFSE) in 3- to 4-day mixed leukocyte reaction co-culture. The ratio of donor- and third-party-induced proliferation (CFSE(low)) of the T cells was reported as the immunoreactivity (IR) index for each subset. Rejectors were defined as those who experienced biopsy-proven acute cellular rejection within 60 days of the assay. IR more than 1 signified increased risk of rejection and IR less than 1 implied decreased risk. Results Rejectors (n=16) and Nonrejectors (n=12) were similar in general demographics. Significantly higher counts were observed for all proliferated CFSE(low) T-cell subsets among rejectors, compared with nonrejectors. Logistic regression, leave-one-out cross-validation, and receiver operating characteristic analyses showed that the IR of Tc associated best with biopsy-proven rejection (sensitivity >87.5%, specificity >83.3%). IR of CFSE(low) Tc correlated significantly with IR of proinflammatory, allospecific CD154(+)Tc-M (r=0.682, P=0.005) and inversely with IR of allospecific, antiinflammatory, CTLA4(+)Tc-M (r=-0.638, P=0.047). Conclusions Proliferative alloresponses of Tc cells can identify rejection-prone children receiving SBTx.

The multivisceral liver-intestine-pancreas-stomach allograft was first described by Starzl nearly 50 years ago. Since then, over 1000 children have received small bowel transplantation (SBTx), alone or with the liver and other organs, for refractory short gut syndrome (SGS) because of a variety of congenital conditions. In 2001, SBTx was approved as definitive therapy for SGS by Medicare. Currently, 1- and 5-year graft survival routinely exceeds 90% and 80%, respectively. The expected outcomes also include freedom from parenteral nutrition, normalization of growth parameters, and quality of life. However, recurrent rejection, complications of high-dose immunosuppression, or chronic rejection, which is more likely to occur after SBTx without a liver graft, account for differences between early and late survival. Future efforts aimed at overcoming such challenges include preventing SBTx through early referral to comprehensive SGS management programs and understanding why the liver protects the small bowel allograft from rejection. Finally, inflammatory mechanisms, which predispose the highly immunogenic small bowel allograft to a protracted risk of resistant rejection must be elucidated, in order to ensure durable success.

Background. Acute cellular rejection affects more than 60% of children after small bowel transplantation (SBTx). Dendritic cells (DCs) are potent antigen-presenting cells, modulate immune responses to gut microbes, and may serve as markers of rejection-prone small bowel transplantation (SBTx). Methods. Myeloid CD11c + DC (MDC), which may have inflammatory functions, and plasmacytoid CD123 + DC (PDC), which may have tolerogenic potential, were measured by flow cytometric analysis, longitudinally (pretransplant, and at days 1 to 60, 61 to 200 posttransplant) in 23 children after SBTx. All children received cadaveric allografts with rabbit anti-human thymocyte globulin induction and steroid-free tacrolimus maintenance therapy. Rejectors were those children (n= 16), who experienced biopsy-proven acute cellular rejection within 60 days of SBTx. Results. Of 69 maximum possible observations, 62 were available for analysis. Among rejectors, a significantly higher MDC:PDC ratio (P=0.004) was associated with numerically higher MDC counts and significantly lower PDC frequencies (P=0.017) during the 1- to 60-day time period, compared with nonrejectors. Logistic regression analysis, leave-one-out cross-validation, and receiver operating characteristic analysis revealed that MDC:PDC ratio more than or equal to 1.52 was associated with rejector status with sensitivity/specificity of 86/67% during the 1 - to 60-day risk period for early SBTx rejection. Repeated measures analysis showed a significantly higher MDC:PDC ratio (P=0.043, F-test) among rejectors, compared with nonrejectors in cumulative data for pre-SBTx and 1- to 60-day time points. No correlation was seen between DC subsets and tacrolimus blood concentration at any time point. Conclusions. We conclude that an elevated MDC:PDC ratio associates with early small bowel allograft rejection and may, therefore, identify at-risk recipients in the clinic.

Background. Early experience with intestinal and multivisceral transplantation was plagued with high risk of rejection and posttransplant lymphoproliferative disorders (PTLD). To improve outcome, innovative management and immunosuppressant strategies were sequentially evolved. Methods. With initiation of the program in 1990, serial monitoring of Epstein-Barr-Viral load was introduced in 1994 with adoption of preemptive antiviral therapy. In 1995, cyclophosphamide or daclizumab induction was added to the tacrolimus-steroid-based multiple drug immunosuppressions. Such a conventional approach was replaced in 2001 with a novel immunosuppressive protocol consisting of recipient pretreatment with a single dose of rabbit antithymocyte globulin or alemtuzumab and posttransplant tacrolimus monotherapy. Results. With a total of 395 consecutive primary recipients, de novo malignancy(s) developed in 61 (15%) patients, with PTLD in 52 (13%), and nonlymphoid cancer (NLC) in 13 (3.2%). Malignancy was donor driven in 3 (4.6%) recipients and associated with graft-versus-host disease in 7 (11.4%). Children were at a significantly higher risk (P

Calcineurin inhibitor nephrotoxicity in nonrenal allograft recipients can lead to end-stage renal disease and the need for kidney transplantation. We sought to evaluate the role of alemtuzumab induction in this population.We evaluated 144 patients undergoing kidney transplantation after nonrenal transplantation between May 18, 1998, and October 8, 2007. Seventy-two patients transplanted between January 15, 2003, and October 8, 2007, received alemtuzumab induction and continued their pretransplant immunosuppression. Seventy-two patients transplanted between May 18, 1998, and July 21, 2007, did not receive alemtuzumab induction, but received additional steroids and maintenance immunosuppression. Donor and recipient demographics were comparable.Overall, 1- and 3-year patient survival and renal function were comparable between the two groups. One- and 3-year graft survival was 93.0% and 75.3% in the alemtuzumab group and 83.3% and 68.7% in the no alemtuzumab group, respectively (P=0.051). The incidence of acute rejection was lower in the alemtuzumab group, 15.3%, than in the no alemtuzumab group, 41.7% (P=0.0001). The incidence of delayed graft function was lower in the alemtuzumab group, 9.7%, than in the no alemtuzumab group, 25.0% (P=0.003). The incidence of viral complications was comparable.Alemtuzumab induction with simple resumption of baseline immunosuppression in patients undergoing kidney transplantation after nonrenal transplantation represents a reasonable immunosuppressive strategy.

Introduction of new innovative immunosuppressive strategies has been the milestone of the recent evolution of intestinal and multivisceral transplantation. With new insights into the mechanisms of organ engraftment and acquired tolerance, the Pittsburgh tolerogenic protocol was recently introduced and consisted of two main therapeutic principles: recipient pretreatment with lymphoid ablating antibodies and minimal post-transplant immunosuppression with tacrolimus monotherapy. The reported herein improved survival and the striking ability to wean immunosuppression among the intestinal and multivisceral recipients pretreated with a single-dose of Thymoglobulin (rATG) or Campath-1H (alemtuzumab) supports our working hypothesis with successful induction of variable tolerance. It is important, however, that careful monitoring of subtle histologic changes in serial endoscopic-guided mucosal biopsies be carried out for early diagnosis of allograft immune activation with prompt restoration of the baseline immunosuppressive therapy. Future scientific discoveries with better understanding of the mechanisms of immune tolerance and clinical introduction of reliable assays will increase the chance and safety of achieving complete tolerance among the intestinal and other solid organ recipients. This review will focus on the historic evolution of the immunosuppressive and other management strategies utilized for the intestinal and multivisceral recipients at the University of Pittsburgh with special reference to allograft immunity and the successful achievement of partial tolerance.

Background Intestinal retransplantation (Re-ITx) has historically been associated with high morbidity and mortality. Methods The outcomes of all children receiving Re-ITx between 1990 and 2007 at our center were reviewed. Results One hundred seventy-two children received primary intestinal grafts. Fourteen children (8.1%) were retransplanted with 15 grafts. Causes of graft failure were acute cellular rejection (ACR, n=4), liver failure (n=2), chronic rejection (n=3), posttransplant lymphoproliferative disorder (n=1), graft dysmotility or dysfunction (n=3), ACR with severe infection (n=1), and arterial graft aneurysm (n=1). Initial transplants were isolated bowel in nine, liver-bowel in five, and one multivisceral. The mean time of initial graft survival was 34.2 months. Re-ITx was with isolated bowel in two, liver-bowel in four, and multivisceral in nine (four with kidney). Initial immunosuppression was Tac-Pred based in nine and rabbit antithymocyte globulin-Tac based in six cases. Re-ITx was carried out under Tac-Pred in six, rabbit antithymocyte globulin-Tac in eight, and alemtuzumab monoclonal anti-CD52 antibody in one. Ten (71.4%) patients are alive with functioning grafts at a mean current follow-up time of 55.9 months. Four patients died from posttransplant lymphoproliferative disorder, severe ACR, fungal sepsis, and bleeding from pseudoaneurysm, respectively, at a mean time of 5.7 months post-Re-ITx. All surviving patients weaned-off total parenteral nutrition at a median time of 32 days and 90% are off intravenous fluids. Conclusions Improved long-term survival and outcome in pediatric Re-ITx may be attributed to improvements in initial immunosuppression protocols, technical modifications, proper timing, and improved infectious disease monitoring. Careful patient selection and posttransplant management are essential for successful long-term outcome.

Background Cytomegalovirus (CMV) infection in immunocompromised patients can lead to viremia associated with morbidity and mortality. Monitoring of viral loads in blood is critical for initiating and monitoring antiviral treatment. Objectives Validate quantitative real-time PCR assay targeting the US17 and UL54 regions of the CMV genome for automated DNA and extraction and amplification. Study design 3422 blood specimens from organ transplant recipients, including longitudinal specimens from 12 organ transplant recipients, were tested by CMV PCR and pp65 antigenemia. Results CMV PCR for both US17 and UL54, was more sensitive and detected CMV DNA earlier and for longer than the CMV pp65 antigenemia test. Using antigenemia results as a reference standard, an optimal cutoff of 500 normalized copies was calculated for both US17 and UL54 PCR targets based on high sensitivity, specificity, and positive and negative predictive values. CMV DNA levels tracked well with clinical symptoms, response to treatment, and antigenemia. Conclusions Detection of persistent increases in CMV DNA levels above 500 normalized copies by this real-time PCR assay is indicative of symptomatic CMV disease in organ transplant recipients. Quantitative real-time PCR for CMV DNA can be used in lieu of antigenemia for monitoring CMV infection and determining when to initiate preemptive treatment.

Intestinal transplantation has been increasingly performed in patients with short bowel syndrome and irreversible gut failure with successful outcomes. In parallel a common association was observed between gut failure and different urological disorders. To our knowledge this study is the first to address such an important clinical observation with special reference to the underlying disease.The medical records of 175 consecutive adult intestinal recipients were reviewed. Data were compiled and described according to the documented urogenital disorder, cause of intestinal failure and treatment modality, including transplantation.Of the patients 43 experienced a total of 53 urogenital disorders for an overall incidence of 25%, including 24 (56%) who had the disorder before referral and 19 (44%) in whom the morbidity developed as a result of transplantation. Interestingly hypercoagulability, pseudo-obstruction, Crohn's disease and Gardner's syndrome were the underlying urogenital and intestinal disorder pathologies in 6.3% of the study patients. Treatment for prior urogenital disorders, including malignancy, precipitated intestinal failure in 3.4% of the referred patients. Reciprocally surgical treatment for the primary intestinal disease and management of gut failure by total parenteral nutrition, followed by transplantation, resulted in different urogenital complications in 17.7% of the total population with an 8.6% incidence of chronic renal failure.Gut failure and intestinal transplantation are commonly associated with different urogenital disorders. Accordingly a designated urological service should be considered part of the multidisciplinary team required for treating this unique population.

Bariatric surgery (BS) is currently the most effective treatment for severe obesity. However, these weight loss procedures may result in the development of gut failure (GF) with the need for total parenteral nutrition (TPN). This retrospective study is the first to address the anatomic and functional spectrum of BS-associated GF with innovative surgical modalities to restore gut function.Over 2 decades, 1500 adults with GF were referred with history of BS in 142 (9%). Of these, 131 (92%) were evaluated and received multidisciplinary care. GF was due to catastrophic gut loss (Type-I, 42%), technical complications (Type-II, 33%), and dysfunctional syndromes (Type-III, 25%). Primary bariatric procedures were malabsorptive (5%), restrictive (19%), and combined (76%). TPN duration ranged from 2 to 252 months.Restorative surgery was performed in 116 (89%) patients with utilization of visceral transplantation as a rescue therapy in 23 (20%). With a total of 317 surgical procedures, 198 (62%) were autologous reconstructions; 88 (44%) foregut, 100 (51%) midgut, and 10 (5%) hindgut. An interposition alimentary conduit was used in 7 (6%) patients. Reversal of BS was indicated in 84 (72%) and intestinal lengthening was required in 10 (9%). Cumulative patient survival was 96% at 1 year, 84% at 5 years, and 72% at 15 years. Nutritional autonomy was restored in 83% of current survivors with persistence or relapse of obesity in 23%.GF is a rare but serious life-threatening complication after BS. Successful outcome is achievable with comprehensive management, including reconstructive surgery and visceral transplantation.

Background Long-term use of immunosuppressants is associated with significant morbidity and mortality in transplant recipients. A simple whole blood assay that has U.S. Food and Drug Administration clearance directly assesses the net state of immune function of allograft recipients for better individualization of therapy. A meta-analysis of 504 solid organ transplant recipients (heart, kidney, kidney-pancreas, liver and small bowel) from 10 U.S. centers was performed using the Cylex ImmuKnow assay. Methods Blood samples were taken from recipients at various times posttransplant and compared with clinical course (stable, rejection, infection). In this analysis, 39 biopsy-proven cellular rejections and 66 diagnosed infections occurred. Odds ratios of infection or rejection were calculated based on measured immune response values. Results A recipient with an immune response value of 25 ng/ml adenosine triphosphate (ATP) was 12 times (95% confidence of 4 to 36) more likely to develop an infection than a recipient with a stronger immune response. Similarly, a recipient with an immune response of 700 ng/ml ATP was 30 times (95% confidence of 8 to 112) more likely to develop a cellular rejection than a recipient with a lower immune response value. Of note is the intersection of odds ratio curves for infection and rejection in the moderate immune response zone (280 ng/ml ATP). This intersection of risk curves provides an immunological target of immune function for solid organ recipients. Conclusion These data show that the Cylex ImmuKnow assay has a high negative predictive value and provides a target immunological response zone for minimizing risk and managing patients to stability.

We report herein the histopathologic characteristics of human intestine allograft acute rejection in a consecutive series of 48 patients receiving small bowel transplantations and treated with a preconditioning protocol between July 4, 2001 and January 31, 2004.Recipient pretreatment was with an i.v. infusion of 5-10 mg/kg thymoglobulin or 30-60 mg of alemtuzumab (Campath 1H) over several hours prior to revascularization. Postoperative treatment was limited to tacrolimus (target 12-h trough level 10-15 ng/mL) unless additional drugs were needed to treat breakthrough rejection.A total of 3,497 biopsies of the allograft jejunum and/or ileum were obtained. A recently validated histological grading schema was prospectively utilized to grade acute rejection. A total of 116 acute rejection episodes were diagnosed (48 indeterminate, 36 mild, 11 moderate, and 21 severe). Several unique histopathologic features of allograft acute rejection were observed in the pretreated patients. First, scattered lamina propria neutrophilic inflammation often precedes the onset of acute rejection. Second, acute rejection is often associated with more prominent eosinophils in lamina propria or eosinophilic cryptitis. Third, certain acute rejection episodes are characterized by absence of crypts with intact surface villous epithelium. Finally, the mucosal damage associated with moderate or severe acute rejection can completely recover after additional immunosuppressive treatment.This study describes several characteristic histopathologic features of allograft small bowel acute rejection associated with thymoglobulin or alemtuzumab preconditioning. Recognition of these unique histopathologic features will enable accurate diagnosis and ensure successful weaning of immunosuppressive drugs.

Intestinal failure is a condition in which inadequate digestion or absorption of fluid, electrolytes, and nutrients leads to dehydration or malnutrition. The most common cause of intestinal failure is short bowel syndrome (SBS) defined as200 cm of functional small intestine. SBS may result from congenital abnormalities or from surgical resection. For the past 3 decades, patients with severe SBS were managed with home parenteral nutrition (HPN). With the emergence of new therapies, the clinician now has multiple options to treat these patients. These include intestinal rehabilitation regimens whereby patients are treated with specialized oral diets, soluble fiber, oral rehydration solutions (ORS), and trophic factors to enhance absorption. There are also a variety of surgical techniques available to preserve intestinal length. Small bowel and multivisceral transplantation has evolved during the last decade to be a valid therapeutic option for those patients who cannot be rehabilitated or who fail HPN. These are interrelated services designed to offer the patient the best therapeutic options to meet their individual needs. This article reviews the principles associated with the nutrition management of this very complex and diverse group of patients.

Somatropin (rDNA origin) injection (Zorbtive) is a highly purified preparation of human growth hormone (GH) produced from a mammalian cell line by recombinant DNA technology. It is the only human GH approved for the treatment of short bowel syndrome in patients receiving specialised nutritional support. The process of intestinal adaptation begins immediately after surgery and continues for 2-3 years. During this period, the bowel begins to increase fluid and nutrient absorption. Under the influence of tropic factors, such as GH, intestinal adaptation is enhanced. Supplying a therapeutic regimen of GH, optimised diet and glutamine supplementation for 4 weeks to patients with short bowel syndrome who are dependent on parenteral nutrition, has been shown to reduce their long-term requirements for parenteral nutrition.

Immune responses to EBV in immunosuppressed (IS) solid organ transplant (SOTx) recipients have not been well characterized. Here we evaluate the phenotype and function of EBV-specific CD8+ T cells in peripheral blood isolated from "stable" IS SOTx recipients. The EBV-specific CD8+ T cell memory subset distribution in the peripheral blood of patients was examined by flow cytometric analysis using HLA-A2 tetramers incorporating BMLF1 (lytic), and LMP2 and EBNA3A (latent)-derived peptides, in conjunction with mAbs against the CD45RO, CD45RA, and CD62L markers. The ability of CD8+ T cells to produce IFN-gamma in response to the same EBV-derived peptides was measured by ELISPOT assay. Patients and healthy normal donors exhibited similar anti-EBV CD8+ T cell frequencies and specificities against the EBV epitopes evaluated. When compared to healthy normal donors, an overall significant expansion of the CD8+ T cell "effector memory" (CD45RO+/CD62L-) pool, including that of EBV "latent" (LMP2 and EBNA3A)-specific CD8+ T cells was detected in IS SOTx patients. However, the patients' EBV-specific CD8+ T cells showed decreased IFN-gamma production to the EBV-peptide stimulation. These results indicate that the impairment of EBV-specific CD8+ T cell activity is not due to clonal depletion, but is mainly due to impaired functional activation.

Modifications in the timing and dosage of immunosuppression can ameliorate the morbidity and mortality that has prevented widespread use of intestinal transplantation (ITx) in children. Thirty-six patients receiving ITx, aged 5 months to 20 years were given 2-3 mg(kg of rabbit anti-thymocyte globulin (rATG, thymoglobulin) just before ITx, and 2-3 mg(kg postoperatively (total 5 mg(kg). Twice daily doses of tacrolimus (TAC) were begun enterally within 24 h after graft reperfusion with reduction of dose quantity or frequency after 3 months. Prednisone or other agents were given to treat breakthrough rejection. After 8-28 months follow-up (mean 15.8 +/- 5.3), 1- and 2-year patient and graft survival is 100% and 94%, respectively. Despite a 44% incidence of acute rejection in the first month, 16 of the 34 (47%) survivors are on TAC (n = 14) or sirolimus (n = 2) monotherapy; 15 receive TAC plus low dose prednisone; one each receive TAC plus sirolimus, TAC plus azathioprine and TAC plus sirolimus and prednisone. There was a low incidence of immunosuppression-related complications. This strategy of immunosuppression minimized maintenance TAC exposure, facilitated the long-term control of rejection, decreased the incidence of opportunistic infections, and resulted in a high rate of patient and graft survival.

Long-term graft dysfunction and/or graft loss after intestinal transplantation (ITx) is a significant concern. Sclerosing peritonitis (SP) is a manifestation of chronic allograft failure and its presence may also include classic arterial obliterative arteriopathy (OA) as in chronic rejection. We describe the clinical presentation and management of SP occurring after ITx in children. Case records of 121 children undergoing ITx from 1990 to 2003 were reviewed. Three children (2.4%) presented with SP of the intestine allograft at a mean time of 6.6 yr following ITx as follows: age at Tx (yr) 8.2, and 3.7, with indication for ITx being gastroschisis in two and midgut volvulus in one patient. Type of ITx was isolated intestine in one and liver/intestine in two patients. Gross findings of SP included fibrosis/strictures; microscopically SP showed fibrosis/serositis, and fibrous adhesions; one patient had evidence of chronic allograft vasculopathy. All patients presented with clinical signs and symptoms of bowel obstruction and gastrointestinal contrast studies confirmed distal ileal obstruction (DIO). Operative findings confirmed SP and DIO in all patients; all patients were initially treated with distal segmental intestine allograft resection and lysis of the fibrous peel. All three patients recovered, although two required repeat laparotomy, there is only one long-term survival. SP after ITx may be a different manifestation of long-term intestine allograft degeneration. Surgical resection appears to offer palliation.

Intestinal, combined liver-intestinal, and multivisceral transplantation are now considered the standard of care for children and adults with permanent intestinal failure. Early attempts at intestinal transplantation were discouraging because of the high incidence of technical complications, rejection, and infection. Advances in the field of transplantation, including the introduction of tacrolimus, improved surgical techniques, and improvements in postoperative care, have led to a renewed interest in intestinal transplantation since 1990. The most significant achievement, however, has been the effective control of rejection and life-threatening infections. This article focuses on the experience to date of innovative strategies that induce lymphocyte depletion and reduction in the incidence of rejection. In this setting, low-maintenance immunosuppression is clinically achievable with an acceptable rate of allograft rejection. Subsequently, the long-term complications of immunosuppression are significantly reduced with achievement of better long-term survival, and an overall improvement in the quality of life.

Background/Purpose Intestinal transplantation has developed to become the standard of care for patients with irreversible intestinal failure who are not responding to total parenteral nutrition. Once considered experimental, it has taken time and much effort for the procedure to become a clinical reality, with final acceptance primarily because of the vastly improved outcomes. Advances and novel modifications in immunosuppression have been at the forefront of these improvements. The authors review their evolutionary experience with intestinal transplantation, particularly relating changes in immunosuppression protocols to improved outcomes. Methods From July 1990 to December 2003, 122 children received 129 intestinal containing allografts (70 liver/intestine, 42 isolated intestine, 17 multivisceral). Mean age was 5.3 ± 5.2 years, and 55% were boys. Indications for transplantation were mostly short gut syndrome. The allografts were cadaveric, ABO identical (except one), with no immunomodulation. Bone marrow augmentation was used in 29% of the recipients since 1995. T-cell lymphoctytotoxic crossmatch was positive in 24% cases. Immunosuppression protocols can be divided into 3 categories: (i) maintenance tacrolimus and steroids (n = 52, 1990-1995, 1997-1998); (ii) addition of induction therapy with cyclophosphamide (n = 16, 1995-1997) then daclizumab (n = 24, 1998-2001). A third immunosuppressive agent was added in either group where increased immunosuppression was indicated; (iii) pretreatment/induction with antilymphocyte conditioning and steroid-free posttransplantation tacrolimus monotherapy (n = 37, 2002-2003). In this later group, if clinically stable at 60 to 90 days posttransplantation, and no recent rejection, the tacrolimus was weaned by decreasing frequency of dosing. Results The overall Kaplan-Meier patient/graft survival was 81%/76% at 1 year, 62%/60% at 3 years, and 61%/51% at 5 years. Survival continues to improve, with 1-year patient/graft survival being 71%/62%, 77%/75%, and 100%/100% for groups (i), (ii), and (iii), respectively. Acute intestinal allograft rejection has decreased markedly in group (iii). The rate of infectious diseases, such as cytomegalovirus and Epstein-Barr virus, is lowest in group (iii). Graft-versus-host disease has not significantly increased with the latest protocol. Most importantly, the overall level of immunosuppression requirements has decreased markedly, with most patients in group (iii) being on monotherapy. Of these, most had their monotherapy weaned down to spaced doses, something never systematically attempted or achieved in pediatric intestinal transplantation. Conclusions Intestinal transplantation has progressed markedly over the last 13 years. Although there have been modifications in all aspects of the procedure, the story of intestinal transplantation has been the evolution of successful immunosuppression regimens. Our latest pretreatment/induction conditioning and posttransplantation monotherapy strategy improves graft acceptance and lowers subsequent immunosuppression dosing requirements. It is expected this will overcome many of the complications related to the previously high immunosuppression requirements. Minimization of immunosuppression with avoidance of steroid therapy offers profound long-term benefits, especially in the pediatric population. The patients still remain challenging and complex in every aspect; however, these advances offer significant hope to both patients and caregivers alike.

Humoral rejection of human small bowel allografts has not been well documented. The aim of this study was to determine the significance of preformed IgG lymphocytotoxic antibodies, as determined by the modified Amos crossmatch technique, in 6 of 28 (21.4%) adult isolated intestinal allograft recipients treated with tacrolimus basal immunosuppression. The crossmatch with dithiothreitol (DTT) was strongly positive in 5 grafts and weakly positive in the remaining one. The strongly positive crossmatch grafts (n=5) developed severe mucosal injuries immediately after reperfusion. Within the first 10 days after transplantation, 3 of the 5 strongly positive crossmatch grafts developed clinically and endoscopically documented severe mucosal congestion, cyanotic discoloration, and focal hemorrhage within the allograft. Simultaneous mucosal biopsy specimens demonstrated severe congestion, neutrophilic margination, and fibrin-platelet thrombi within the lamina propria microvasculature, along with focal hemorrhage, but with no histological neutrophilic or necrotizing arteritis, and the immunofluorescent findings were unremarkable. The other 2 strongly positive crossmatch allograft recipients developed macroscopic congestion of mucosa with microscopic foci of congestion and hemorrhage. In contrast, the recipient with a weakly positive crossmatch, as well as the 22 crossmatch negative recipients, exhibited none of these characteristic clinical, endoscopic, or microscopic findings (P.05). With prompt augmentation of the immunosuppression therapy, the 3 grafts with the characteristic clinicopathologic syndrome were successfully reversed with the monoclonal antilymphocyte preparation OKT3. Thus there was no statistical difference (P.05) in early graft survival and the frequency of acute rejection episodes between the crossmatch-positive and the crossmatch-negative groups within the first 6 months after transplantation. We conclude that preformed IgG lymphocytotoxic antibodies in isolated intestinal recipients can be associated with a characteristic clinicopathologic syndrome during the early postoperative course, similar to that observed in experimental animal models and in other solid organ transplantation. If recognized and treated aggressively, early graft failure can be avoided. The long-term significance of these preformed antibodies has yet to be determined.

Background. Maintenance immunosuppression required after organ transplantation creates a permissive environment in which cancer cells can proliferate because of lack of natural immunologic surveillance. With more than a decade of clinical experience, this report is the first to address the risk of de novo cancer after intestinal transplantation. Methods. A total of 168 consecutive intestinal transplant recipients (86 children and 82 adults) were studied, of whom 52% were male and 91% were white. Surveillance, Epidemiology, and End Results data was used to count expected rates of de novo cancers in the general population matched for age, sex, and length of follow-up. Results. With a mean follow-up of 4741 months, 7 (4.2%) patients developed nonlymphoid de novo cancer, with a cumulative risk of 3% at 5 years and 28% at 10 years. Of these malignancies, one was donor-driven adenocarcinoma. With 0.58 being the expected rate of malignancy for the general population, the risk among intestinal recipients was 8.7 times higher (P0.01). Such morbidity was significantly higher (50 times) among younger patients (

Although the reductionist approach has served science well for 400 years, the accumulation of details can obscure the truth if the original premise is incorrect. One such premise has been that successful organ transplantation and bone marrow engraftment are fundamentally different outcomes involving separate and distinct mechanisms. Some historical clinical observations pointed to a different conclusion almost from the beginning and included clues about how to induce tolerance with the aid of immunosuppression.

Liver, small intestine, and heart allografts in residence for 4 days to 16 years were analyzed by simultaneous XY fluorescent in situ hybridization to search for evidence of the recently described process of transdifferentiation of recipient bone marrow stem cells to allograft parenchymal cells. These studies were carried out in an effort to find conditions associated with maximal levels of engraftment or expansion of the recipient parenchymal cells. Despite prolonged survival up to 16 years, regeneration after severe preservation injury or use of split livers, only rare, isolated and tentatively identified recipient hepatocytes were detected in liver allografts. In intestinal allografts, despite survival of up to 8 years and extensive mucosal regeneration because of severe damage from acute rejection, there was no crypt replacement by recipient epithelial cells. In cardiac allografts, no recipient myocytes were detected despite recipient survival for 2-3 days and 3-4 weeks after myocardial infarcts at 5 and 8 years after transplantation. Parenchymal cell transdifferentiation from recipient bone marrow stem cells was rare to nonexistent in severely injured, regenerating, and long-surviving allografts. The rare isolated recipient parenchymal cells tentatively identified did not appear to behave as stem cells: they did not form clusters and did not increase with time after transplantation. Because of the extremely low frequency, interpretation was difficult. Regardless of these results, a more vigorous search for conditions that promote transdifferentiation is warranted.

Passenger leukocytes have been demonstrated to play significant roles in initiating and also regulating immune reactions after organ transplantation. Reliable techniques to detect donor leukocytes in recipients after organ transplantation are essential to analyze the role, function, and behavior of these leukocytes. In this report we describe a simple, reliable method to detect donor cells with low frequencies using peripheral blood samples. Detection of small numbers of major histocompatibility complex (MHC) mismatched cells was first studied using four-color flow cytometry in artificially created cell mixtures. By selecting the CD45(+) population and simultaneous staining with several leukocyte lineage markers (CD3, CD4, CD8, CD56, and CD19), MHC-mismatched leukocytes were consistently detected in cell suspensions prepared from directly stained whole blood samples with a threshold sensitivity as low as 0.1%-0.2%. When the fresh peripheral blood mononuclear cells were separated by conventional Ficoll gradient purification, similar, but slightly lower levels of donor cells were detected. Blood samples obtained 1-5 months after liver, kidney, and intestine transplants revealed that the kind of organ allograft influenced levels and lineage pattern of the circulating donor cells. This procedure provided a simple and reliable method in determining early chimerism in transplant recipients. However, the detection of MHC-mismatched leukocytes of all lineages was much lower when frozen peripheral blood mononuclear cells were used.

The objective of this study was to describe the dynamics of nutrition management of intestinal transplant recipients and allograft functional autonomy.Intestinal absorptive functions and recipient nutritional status were monitored during the 12-month study period. Absorption was evaluated with D-xylose absorption and fecal fat excretion. Indices for nutrition were body weight, anthropometric measures, and serum albumin.Before transplant, all patients were total parenteral nutrition (TPN) dependent and well nourished. By the first postoperative month, all 22 recipients were tolerating enteral feeding. By 3 months, all recipients had begun oral feeding, with 13 off TPN and 7 off enteral feeds. By 6 months, 16 recipients were off TPN, and by the end of the 12th month, 17 (77%) were free of TPN. Although all 22 recipients were completely weaned off TPN during the first posttransplant year, 10 required temporary reinstitution of therapy at different points. Full nutritional autonomy was achieved at 3 months by 3 recipients, at 6 months by 8 recipients, and at 12 months by 12 (55%) recipients.These results reflect our early experience that led to surgical refinement of the operation and evolution of the recipient postoperative management. Nonetheless, even in this initial cohort, most of the engrafted intestines restored the recipient nutritional autonomy, and all survivors remained well nourished.

One hundred and seventy-two patients underwent small bowel transplantation at Children's Hospital of Pittsburgh and University of Pittsburgh Medical Center between May 1990 and August 2001. Thirty-four patients had complete or partial resection of their primary graft and in 15, histologic features of chronic rejection were present in the resected small bowel. This is a descriptive and correlative study of the demographic, perioperative, and histologic features associated with progression to intestinal graft failure. Variable features associated with an increased risk of chronic rejection included acute rejection within the 1st month, increased number and higher grade of acute rejection episodes, isolated small bowel grafts rather than small bowel–liver grafts, older recipient age, non-Caucasian race, and Caucasian to non-Caucasian transplant. The mucosal biopsies showed predictive changes many months before the grafts were excised. The mucosal biopsy diagnosis of chronic vascular rejection can be difficult because the affected vessels, the distal branches of the mesenteric arteries, and the larger arteries of the subserosa and submucosa are not routinely sampled. The possibility of underlying arteriopathy, however, can be inferred in some instances from the presence of secondary mucosal changes in the small bowel biopsies though the “early” changes lack specificity. It is the progression of biopsy findings over time that is predictive of outcome. It is important to recognize the persistence of “late” mucosal changes of chronic rejection so that patients are not subjected to increased immune suppression when it is unlikely to be of significant benefit.