Current approaches for risk assessment of intestinal transplant patients: A view from the histocompatibility laboratory.

Despite its recent decline in volumes, intestinal transplantation remains an important option for patients with irreversible intestinal failures. The long-term outcome of an intestinal transplant has stagnated. The major cause of graft loss is rejection, resulting from mismatches in human leukocyte antigens (HLA) and the presence of antibodies to mismatched donor-specific HLA antigens (DSA). Literature has reported that DSAs, either preformed before transplantation or developed de novo after transplantation, are harmful to intestinal grafts, especially for those without combined liver grafts. A comprehensive assessment of DSA by the histocompatibility laboratory is critical for successful intestinal transplantation and its long-term survival. This paper briefly reviews the history and current status of different methods for detecting DSA and their clinical applications in intestinal transplantation. The focus is on applying different antibody assays to manage immunologically challenging intestinal transplant patients before and after transplantation. A clinical case is presented to illustrate the complexity of HLA tests and the necessity of multiple assays. The review of risk assessment by the histocompatibility laboratory also highlights the need for close interaction between the laboratory and the intestinal transplant program.

Intestinal and Multivisceral Transplantation: Complications.

Advancements in immunosuppression protocols, surgical techniques, and postoperative care in the last few decades have improved outcomes of intestinal transplant patients. Normal immediate postoperative imaging appearance can simulate pathology. Intestinal transplant recipients are prone for several postoperative complications due to the complex surgical technique, which involves multiple anastomoses, and immunogenic nature of the allograft intestine. Imaging plays a crucial role in detection of several major complications including infectious, immunologic, vascular, gastrointestinal, pancreaticobiliary, genitourinary, and neoplastic complications. The awareness of the posttransplant anatomy and normal imaging appearances helps radiologists anticipate and accurately detect posttransplant complications.

Safe Use of Erythromycin For Refractory Gastroparesis After Small Bowel Transplantation.

Current therapeutic options with prokinetic agents for posttransplant gastroparesis are limited. Erythromycin is associated with adverse reactions, including corrected QT interval prolongation and cytochrome P450 3A4 isoenzyme inhibition. The use of erythromycin has been avoided in patients undergoing treatment with cyclosporine or tacrolimus because of significant fluctuations in therapeutic immunosuppression levels. We report herein the successful use of erythromycin after visceral transplant to treat delayed gastric emptying. Two patients were managed with oral erythromycin (initial dose of 750 mg/d divided into 3 doses) for gastroparesis after visceral transplant. Patient 1 was a woman aged 42 years with a history of chronic intestinal pseudo-obstruction syndrome who underwent isolated small bowel transplant with dual (gastric and duodenal) proximal allograft anastomosis. Posttransplant gastroparesis was initially managed with oral metoclopramide. The patient also required high doses of tacrolimus (36 mg/d) to maintain adequate immunosuppression levels. The decision was made to change metoclopramide to erythromycin, which significantly decreased the daily tacrolimus dose requirement (from 36 to 9 mg/d), with resolution of nausea and intermittent bloating symptoms. Patient 2 was a woman aged 35 years with ultra-short gut syndrome after extensive enterectomy due to intestinal volvulus who underwent uneventful combined intestinal and colon transplant. Conventional pharmacologic therapy for gastroparesis was initiated after surgery without success. Erythromycin was started 15 days posttransplant, with significant improvement in her symptoms, and discontinued 47 days post-transplant. To maintain therapeutic levels (8-10 mg/dL), daily tacrolimus dose was decreased 75.8% and 36.5% for patients 1 and 2, respectively. No significant side effects associated with erythromycin use were observed in either patient. Our findings here suggest that erythromycin may be safely used for gastroparesis after small bowel transplant. Close monitoring of immunosuppressive drug levels and dose adjustments of other medications affected by inhibition of cytochrome P450 3A4 are advised.

Modified Antimesenteric Tapering Enteroplasty: An Alternative Technique for the Treatment of Dysfunctional Anastomosis in Patients With Short Bowel.

INTRODUCTION: Several techniques have been described to taper the dilated small bowel to improve intestinal motility and decrease complications related to overdilated small bowel, including longitudinal intestinal lengthening and tapering, serial transverse enteroplasty, and spiral intestinal lengthening and tailoring. We propose an alternative technique designed to optimize bowel function and minimize the effects of recurrent small-bowel bacterial overgrowth in patients with short or ultra-short gut syndrome and dysfunctional anastomosis with maintenance of the actual absorptive surface. TECHNIQUE: The dilated side-to-side anastomosis is identified, and the mesentery leaves from both the proximal and distal small-bowel loops are separated by using blunt dissection. The previous anastomosis is divided longitudinally with a GI stapler. Once the small-bowel transection is completed, 2 separate blind loops of intestine are created, each one with half the circumference of the dilated side-to-side anastomosis. The antimesenteric stapled line is then reinforced with an outer layer of running suture. The blind loops of the tapered small bowel are then trimmed and anastomosed in an end-to-end isoperistaltic fashion in 2 layers. RESULTS: There were no postoperative complications. The length of the tapering ranged from 10 to 23 cm, corresponding to approximately 16% (range, 13%-20%) of the remaining small-bowel length. Three of 4 patients presented significant improvement of their symptoms and were able to have their parenteral support discontinued. CONCLUSIONS: Modified antimesenteric tapering enteroplasty is an alternative technique to improve intestinal motility and treat patients with short-bowel syndrome and dysfunctional side-to-side anastomosis without the need for further small-bowel resection. This bowel-sparing technique represents a valuable option in the armamentarium of the surgeon who manages patients with intestinal failure.

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.

Ethacrynic acid decreases expression of proinflammatory intestinal wall cytokines and ameliorates gastrointestinal stasis in murine postoperative ileus.

OBJECTIVES: Several compounds characterized by an olefin linkage conjugated to a carbonyl group have anti-inflammatory properties. The diuretic ethacrynic acid (EA) is a compound of this type. Herein, we tested the hypothesis that ethacrynic acid can modulate the development of ileus after bowel manipulation. METHODS: Groups (n=9) of male C57Bl/6 mice underwent surgical manipulation of the small intestine using a pair of cotton-tipped applicators (MAN). Control animals (CONT) did not undergo any surgical intervention or receive treatment. MAN mice were pre- and post-treated with four intraperitoneal doses of phosphate buffered saline (PBS), EA1 (1mg/kg per dose), or EA10 (10mg/kg per dose). Gastrointestinal transit of non-absorbable FITC-labeled dextran was assessed by gavaging the mice with the tracer 24h after operation and assessing FD70 concentration 120 min later in the bowel contents from the stomach, 10 equally long segments of small intestine, cecum, and two equally long segments of colon. The geometric center for the tracer was calculated for each animal. Expression of interleukin-6 (IL-6) and inducible nitric oxide synthase (iNOS) transcripts in the ileal muscularis propria was assessed using semiquantitative reverse transcriptase-polymerase chain reaction. RESULTS: In control animals, the mean (±SE) geometric center for the transit marker was 9.89±0.47, whereas it was 4.59±0.59 for PBS-treated animals (p<0.05 vs CONT). The geometric center for pre- post treatment with low (1mg/kg) and high (10mg/kg) doses of ethacrynic acid were 7.23±0.97 and 5.15±0.57, respectively. Compared to PBS, treatment with ethacrynic acid (1mg/kg) significantly decreased manipulation-induced IL-6 and iNOS mRNA expression in the wall of the small bowel. CONCLUSIONS: Pre- and post-treatment with ethacrynic acid ameliorates ileus and modulates inflammation in the gut wall induced by bowel manipulation.

Outcomes of Adult Intestinal Transplant Recipients Requiring Dialysis and Renal Transplantation.

BACKGROUND: Data on dialysis and renal transplantation (RT) after intestinal transplantation (IT) are sparse. Whether changes in immunosuppression and surgical techniques have modified these outcomes is unknown. METHODS: Two hundred eighty-eight adult intestinal transplants performed between 1990 and 2014 at the University of Pittsburgh were analyzed for incidence, risk factors and outcomes after dialysis and RT. Cohort was divided into 3 eras based on immunosuppression and surgical technique (1990-1994, 1995-2001, and 2001-2014). Receiving RT, or dialysis for 90 days or longer was considered as end-stage renal disease (ESRD). RESULTS: During a median follow-up of 5.7 years, 71 (24.7%) patients required dialysis, 38 (13.2%) required long-term dialysis and 17 (6%) received RT after IT. One-, 3-, and 5-year ESRD risk was 2%, 7%, and 14%, respectively. No significant era-based differences were noted. Higher baseline creatinine (hazard ratio [HR], 3.40 per unit increase, P < 0.01) and use of liver containing grafts (HR, 2.01; P = 0.04) had an increased ESRD risk. Median patient survival after dialysis initiation was 6 months, with a 3-year survival of 21%. Any dialysis (HR, 12.74; 95% CI 8.46-19.20; P < 0.01) and ESRD (HR, 9.53; 95% CI, 5.87-15.49; P < 0.01) had higher mortality after adjusting for covariates. For renal after IT, 1- and 3-year kidney and patient survivals were 70% and 49%, respectively. All graft losses were from death with a functioning graft, primarily related to infectious complications (55%). CONCLUSIONS: In intestinal transplant recipients, renal failure requiring dialysis or RT is high and is associated with increased mortality. Additionally, the outcomes for kidney after IT are suboptimal due to death with a functioning graft.

Ileocecal Anastomosis Type Significantly Influences Long-Term Functional Status, Quality of Life, and Healthcare Utilization in Postoperative Crohn's Disease Patients Independent of Inflammation Recurrence.

OBJECTIVES: Anastomotic reconstruction following intestinal resection in Crohn's disease (CD) may employ side-to-side anastomosis (STSA; anti-peristaltic orientation) or end-to-end anastomosis (ETEA). Our aim was to determine the impact of these two anastomotic techniques on long-term clinical status in postoperative CD patients. METHODS: We performed a comparative effectiveness study of prospectively collected observational data from consented CD patients undergoing their first or second ileocolonic bowel resection and re-anastomosis between 2008 and 2012, in order to assess the association between anastomosis type and 2-year postoperative quality of life (QoL), healthcare utilization, disease clinical or endoscopic recurrence, use of medications, and need for repeat resection. RESULTS: One hundred and twenty eight postoperative CD patients (60 STSA and 68 ETEA) were evaluated. At 2 years postoperatively, STSA patients had higher rates of emergency department visits (33.3% vs. 14.7%; P=0.01), hospitalizations (30% vs. 11.8%; P=0.01), and abdominal computed tomography scans (50% vs. 13.2%; P<0.001) with lower QoL (mean short inflammatory bowel disease questionnaire 47.9 vs. 53.4; P=0.007). There was no difference among the two groups in the 30 day surgical complications and 2-year patterns of disease activity, CD medication requirement, endoscopic recurrence, and need for new surgical management (all P > 0.05). CONCLUSIONS: At 2 years postoperatively, CD patients with ETEA demonstrated better QoL and less healthcare utilization compared with STSA, despite having similar patterns of disease recurrence and CD treatment. These findings suggest that surgical reconstruction of the bowel as an intact tube (ETEA) contribute to improved functional and clinical status in patients with CD.

Imaging of Intestinal and Multivisceral Transplantation.

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. ©RSNA, 2018.

Liver-inclusive intestinal transplantation results in decreased alloimmune-mediated rejection but increased infection.

BACKGROUND AND AIMS: A co-transplanted liver allograft has been thought to protect other organs from rejection-mediated injury; however, detailed analyses of co-transplanted liver on intestinal allograft outcomes have not been conducted to date. The aim of the study was to compare immune-mediated injury, causes of graft failure and clinical outcomes between recipients who underwent either a liver-inclusive intestinal transplant (LITx) or liver-exclusive intestinal transplant (LETx). METHODS: Between May 2000 and May 2010, 212 adult patients undergoing LITx (n =76) and LETx (n =136) were included. LITx underwent either liver combined intestinal or full multivisceral transplantation. LETx underwent either isolated intestinal or modified multivisceral transplantation. RESULTS: During 44.9 ± 31.4 months of follow-up, death-censored intestinal graft survival was significantly higher for LITx than LETx (96.9%, 93.2% and 89.9% vs 91.4%, 69.3% and 60.0% at 1, 3 and 5 years; p =0.0001). Incidence of graft loss due to rejection was higher in LETx than in LITx (30.9% vs 6.6%; p <0.0001), while infection was the leading cause of graft loss due to patient death in LITx (25.0% vs 5.1%; p <0.0001). Despite similar immunosuppression, the average number (0.87 vs 1.42, p =0.02) and severity of acute cellular rejection episode (severe grade: 7.9% vs 21.3%; p =0.01) were lower in LITx than in LETx. Incidence of acute antibody-mediated rejection was also significantly lower in LITx than in LETx (3.6% vs 15.2%; p =0.03). Incidence of chronic rejection was reduced in LITx (3.9% vs 24.3%; p =0.0002). CONCLUSIONS: Intestinal allografts with a liver component appear to decrease risk of rejection but increase risk of infection. Our findings emphasize that LITx has characteristic immunologic and clinical features. Lower immunosuppression may need to be considered for patients who undergo LITx to attenuate increased risk of infection.

Pediatric liver transplantation for hepatocellular cancer and rare liver malignancies: US multicenter and single-center experience (1981-2015).

A tenth of all pediatric liver transplantations (LTs) are performed for unresectable liver malignancies, especially the more common hepatoblastoma (HBL). Less understood are outcomes after LT for the rare hepatocellular carcinoma, nonhepatoblastoma embryonal tumors (EMBs), and slow growing metastatic neuroendocrine tumors of childhood. Pediatric LT is increasingly performed for rare unresectable liver malignancies other than HBL. We performed a retrospective review of outcomes after LT for malignancy in the multicenter US Scientific Registry of Transplant Recipients (SRTR; n = 677; 1987-2015). We then reviewed the Children's Hospital of Pittsburgh (CHP; n = 74; 1981-2014) experience focusing on LT for unresectable hepatocellular cancer (HCC), EMBs, and metastatic liver tumors (METS). HBL was included to provide reference statistics. In the SRTR database, LT for HCC and HBL increased over time (P < 0.001). Compared with other malignancies, the 149 HCC cases received fewer segmental grafts (P < 0.001) and also experienced 10-year patient survival similar to 15,710 adult HCC LT recipients (51.6% versus 49.6%; P = 0.848, not significant [NS], log-rank test). For 22 of 149 cases with incidental HCC, 10-year patient survival was higher than 127 primary HCC cases (85% [95% confidence interval (CI), 70.6%-100%] versus 48.3% [95% CI, 38%-61%]; P = 0.168, NS) and similar to 3392 biliary atresia cases (89.9%; 95% CI, 88.7%-91%). Actuarial 10-year patient survival for 17 EMBs, 10 METS, and 6 leiomyosarcoma patients exceeded 60%. These survival outcomes were similar to those seen for HBL. At CHP, posttransplant recurrence-free and overall survival among 25 HCC, 17 (68%) of whom had preexisting liver disease, was 16/25 or 64%, and 9/25 or 36%, respectively. All 10 patients with incidental HCC and tumor-node-metastasis stage I and II HCC survived recurrence-free. Only vascular invasion predicted poor survival in multivariate analysis (P < 0.0001). A total of 4 of 5 EMB patients (80%) and all patients with METS (neuroendocrine-2, pseudopapillary pancreatic-1) also survived recurrence-free. Among children, LT can be curative for unresectable HCC confined to the liver and without vascular invasion, incidental HCC, embryonal tumors, and metastatic neuroendocrine tumors. Liver Transplantation 23 1577-1588 2017 AASLD.

Surgical and medical approach to patients requiring total small bowel resection: Managing the "no gut syndrome".

BACKGROUND: Total resection of the jejunum and ileum, a rarely performed procedure, is indicated after mesenteric vascular events, trauma, or resection of abdominal neoplasms. We describe our recent experience with the operative and medical management of patients with "no gut syndrome." METHODS: We retrospectively reviewed 341 adult patients who were referred to our center between January 2013 and December 2016. RESULTS: Thirteen patients with a mean age of 42.5 years (range 17 to 66 years) underwent near total enterectomy. Indications for small bowel resection were vascular event (n = 5), intraabdominal fibroid/desmoid (n = 4), and trauma (n = 4). Foregut secretions were managed with duodenocolostomy (n = 5), tube decompression (n = 5), and end duodenostomy (n = 2). Duodenal stump was stapled off in 4 cases. One patient underwent a spleen-preserving duodenopancreatectomy combined with total enterectomy. Biliary secretions were managed with choledochocolostomy. All patients were discharged on full total parenteral nutrition infused over a 10- to 16-hour period. Average total parenteral nutrition volume and caloric requirement were 2,800 mL/day (range 2,000 to 4,000) and 1,774 Kcal/day (range 1,443 to 2,290), respectively. Patients who underwent duodenocolonic anastomosis received smaller TPN volume (33.8 vs 49.8 mL/kg). Ten patients (77%) required supplemental intravenous fluid. There were no intraoperative or perioperative deaths. One patient was lost to follow-up 2 months after operation. After a 20-month median follow-up (range 4 to 48 months), 9 patients are still alive (75%). All patients with duodenocolostomy remain alive (median follow-up 36.4 months). Three patients underwent uneventful isolated small bowel transplantation, and another 4 are being evaluated or are already listed for visceral transplantation. CONCLUSION: In summary, resection of the entire small bowel is feasible and can be a lifesaving procedure for a select group of patients. Long-term survival can be achieved in specialized centers. In addition, reestablishment of gastrointestinal tract continuity after total enterectomy appears to be the best option for postoperative fluid and electrolyte management.

PREOPERATIVE COMPUTED TOMOGRAPHY VOLUMETRY AND GRAFT WEIGHT ESTIMATION IN ADULT LIVING DONOR LIVER TRANSPLANTATION.

Background: Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. Aim: To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Methods: Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Results: Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r2=0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 - 0.99 (p<0.0001). Conclusion: The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82.

Racional: A volumetria por tomografia computadorizada (VTC) é uma ferramenta útil para a previsão do peso do enxerto (PE) para o transplante hepático com doador vivo (TFDV). Poucos estudos examinaram a correlação entre o VTC e PE no parênquima hepático normal. Objetivo: Analisar a correlação entre VTC e PE em uma população adulta de doadores para o TFDV e realização de revisão sistemática dos modelos matemáticos existentes para calcular o peso de enxertos hepáticos parciais. Métodos: Foram revisados retrospectivamente 28 doadores consecutivos submetidos à hepatectomia direita para o TFDV entre janeiro de 2009 a janeiro de 2013. Todos os doadores eram adultos saudáveis ​​com VTC pré-operatório. Os enxertos foram perfundidos com solução de preservação HTK. O volume estimado foi obtido por VTC e estes valores foram comparados com o peso real do enxerto, o qual foi aferido depois da hepatectomia e perfusão do enxerto. Resultados: A mediana do PE real foi de 782,5 g, média de 791,43±136 g, variando de 520-1185 g. A mediana do volume estimado do enxerto foi de 927,5 ml, média de 944,86±200,74 ml e variou de 600-1477 ml. A regressão linear volume estimado do enxerto e PE real foi significativamente linear (PE=0.82 do volume estimado do enxerto, r2=0,98, declive=0,47, desvio-padrão de 0,024 e p<0,0001). Correlação linear de Spearman foi de 0,65, com IC de 95% do 0,45-0,99 (p<0,0001). Conclusão: A regra de "um-para-um" não deve ser empregada em pacientes com parênquima hepático normal. A melhor estimativa do peso do enxerto hepático de doador vivo pode ser alcançado através da multiplicação do VTC por 0,82.

Allogeneic anorectal transplantation in rats: technical considerations and preliminary results.

Fecal incontinence is a challenging condition with numerous available treatment modalities. Success rates vary across these modalities, and permanent colostomy is often indicated when they fail. For these cases, a novel potential therapeutic strategy is anorectal transplantation (ATx). We performed four isogeneic (Lewis-to-Lewis) and seven allogeneic (Wistar-to-Lewis) ATx procedures. The anorectum was retrieved with a vascular pedicle containing the aorta in continuity with the inferior mesenteric artery and portal vein in continuity with the inferior mesenteric vein. In the recipient, the native anorectal segment was removed and the graft was transplanted by end-to-side aorta-aorta and porto-cava anastomoses and end-to-end colorectal anastomosis. Recipients were sacrificed at the experimental endpoint on postoperative day 30. Surviving animals resumed normal body weight gain and clinical performance within 5 days of surgery. Isografts and 42.9% of allografts achieved normal clinical evolution up to the experimental endpoint. In 57.1% of allografts, signs of immunological rejection (abdominal distention, diarrhea, and anal mucosa inflammation) were observed three weeks after transplantation. Histology revealed moderate to severe rejection in allografts and no signs of rejection in isografts. We describe a feasible model of ATx in rats, which may allow further physiological and immunologic studies.

Successful liver allograft inflow reconstruction with the right gastroepiploic vein.

Portal vein thrombosis is a common complication in cirrhotic patients. When portal vein thrombectomy is not a suitable option, a large collateral vessel can be used for allograft venous inflow reconstruction. We describe an unusual case of successful portal revascularization using the right gastroepiploic vein. The patient underwent a cadaveric orthotopic liver transplantation with end-to-end anastomosis of the portal vein to the right gastroepiploic vein. Six months after liver transplantation the patient is well with good liver function. The use of the right gastroepiploic vein for allograft venous reconstruction is feasible and safe, with a great advantage of avoiding the need of venous jump graft.

Acute antibody-mediated rejection after intestinal transplantation.

AIM: To investigate the incidence, risk factors and clinical outcomes of acute antibody-mediated rejection (ABMR) after intestinal transplantation (ITx). METHODS: A retrospective single-center analysis was performed to identify cases of acute ABMR after ITx, based on the presence of donor-specific antibody (DSA), acute tissue damage, C4d deposition, and allograft dysfunction. RESULTS: Acute ABMR was identified in 18 (10.3%) out of 175 intestinal allografts with an average occurrence of 10 d (range, 4-162) after ITx. All acute ABMR cases were presensitized to donor human leukocyte antigens class I and/or II antigens with a detectable DSA. A positive cross-match was seen in 14 (77.8%) cases and twelve of 18 patients (66.7%) produced newly-formed DSA following ITx. Histological characteristics of acute ABMR include endothelial C4d deposits, interstitial hemorrhage, and severe congestion with focal fibrin thrombin in the lamina propria capillaries. Multivariate analysis identified a liver-free graft and high level of panel reactive antibody as a significant independent risk factor. Despite initial improvement after therapy, eleven recipients (61.1%) lost transplant secondary to rejection. Of those, 9 (50%) underwent graft removal and 4 (22.2%) received second transplantation following acute ABMR. At an average follow-up of 32.3 mo (range, 13.3-76.4), 8 (44.4%) recipients died. CONCLUSION: Our results indicate that acute ABMR is an important cause of intestine graft dysfunction, particularly in a liver-exclusive graft and survivors are at an increased risk of developing refractory acute rejection and chronic rejection. More effective strategies to prevent and manage acute ABMR are needed to improve outcomes.

Autologous Reconstruction and Visceral Transplantation for Management of Patients With Gut Failure After Bariatric Surgery: 20 Years of Experience.

OBJECTIVE: 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. METHODS: 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. RESULTS: 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%. CONCLUSIONS: GF is a rare but serious life-threatening complication after BS. Successful outcome is achievable with comprehensive management, including reconstructive surgery and visceral transplantation.