Georgios Vrakas

A comparison of the outcomes of one-stage and two-stage brachiobasilic arteriovenous fistulas

OBJECTIVE The brachiobasilic arteriovenous fistula (BBAVF) can be formed in one or two stages. This study examined the failure rates and functional patencies of one-stage vs two-stage brachiobasilic transposition fistulas to compare the two surgical techniques. METHODS We retrospectively identified all the patients who underwent BBAVF access surgery at Kings College Hospital between January 1, 2009, and December 31, 2011 (3 years). Patients were divided into two groups according to one-stage or two-stage procedure. All patients were seen in the access clinic 4 to 6 weeks postoperatively, and their fistulas were scanned (duplex). The surveillance of fistulas consists of duplex scans every 6 months to assess volume flow. RESULTS During the study interval, 149 brachiobasilic transpositions (65 one-stage and 84 two-stage) were performed in 141 patients. Patients undergoing the two-stage procedure had a smaller mean preoperative vein diameter (4.0 ± 1.1 vs 3.6 ± 1.3 mm; P = .041) and tended to be older (58 ± 15 vs 63 ± 15 years; P = .062). Mean overall follow-up was 559 ± 333 days. There was no difference in primary failure between the two groups (45% vs 42%; P = .718). At 1 year, the two-stage BBAVFs had significantly better primary (71% vs 87%; P = .034), assisted primary (77% vs 95%; P = .017), and secondary functional (79% vs 95%; P = .026) patencies. The same applied to 2-year primary (53% vs 75%; P = .034), assisted primary (57% vs 77%; P = .017), and secondary functional (57% vs 77%; P = .026) patencies. Multivariate Cox regression showed that the one-stage procedure was 3.2 times more likely to fail (P = .028). Men were 2.7 times more likely to lose their access (P = .054). CONCLUSIONS This study describes a large series of BBAVFs and makes an extensive comparison between the one-stage and two-stage operations. Significantly improved overall functional patency is demonstrated for the two-stage operation.

Abdominal Wall Transplantation: Skin as a Sentinel Marker for Rejection

Abdominal wall transplantation (AWTX) has revolutionized difficult abdominal closure after intestinal transplantation (ITX). More important, the skin of the transplanted abdominal wall (AW) may serve as an immunological tool for differential diagnosis of bowel dysfunction after transplant. Between August 2008 and October 2014, 29 small bowel transplantations were performed in 28 patients (16 male, 12 female; aged 41 ± 13 years). Two groups were identified: the solid organ transplant (SOT) group (n = 15; 12 ITX and 3 modified multivisceral transplantation [MMVTX]) and the SOT‐AWTX group (n = 14; 12 ITX and 2 MMVTX), with the latter including one ITX‐AWTX retransplantation. Two doses of alemtuzumab were used for induction (30 mg, 6 and 24 h after reperfusion), and tacrolimus (trough levels 8–12 ng/mL) was used for maintenance immunosuppression. Patient survival was similar in both groups (67% vs. 61%); however, the SOT‐AWTX group showed faster posttransplant recovery, better intestinal graft survival (79% vs. 60%), a lower intestinal rejection rate (7% vs. 27%) and a lower rate of misdiagnoses in which viral infection was mistaken and treated as rejection (14% vs. 33%). The skin component of the AW may serve as an immune modulator and sentinel marker for immunological activity in the host. This can be a vital tool for timely prevention of intestinal graft rejection and, more important, avoidance of overimmunosuppression in cases of bowel dysfunction not related to graft rejection.

Clinically Significant Peripancreatic Fluid Collections After Simultaneous Pancreas-Kidney Transplantation

Background Peripancreatic fluid collections (PPFC) are a serious complication after simultaneous pancreas-kidney transplantation (SPKTx). Methods Retrospective study for all 223 SPKTx performed from December 8, 1996, to October 10, 2011, to evaluate the risk factors (RF) and impact of PPFCs on outcomes was conducted. Results Clinically significant PPFCs were seen in 36 (16%) cases, all within 3 months after transplantation. Radiologic drainage resolved 2 (6%) cases, and 34 required laparotomy (mean [SD], 4 [7]). Compared with the non-PPFC group (n=186), the PPFC group had similar patient and total kidney graft survivals but significantly lower total pancreas survival (68% vs. 85%) and greater incidence of infections (75% vs. 46%, all P<0.05) at 5 years. PPFCs were associated with early graft pancreatitis in 18 (50%), pancreatic fistula in 20 (56%, 9 with obvious duodenal stump leak) and infection in the collection in 20 (56%) cases. Comparison of PPFCs with pancreas graft loss to the PPFCs with surviving grafts showed that the incidence of pancreatic fistula was greater in the former (90% pancreas graft loss vs. 42% pancreas graft survival, P<0.01). Binary logistic regression analysis of RF for developing PPFC showed a donor age >30 years to be significant (P=0.03; odds ratio, 3.4; confidence interval, 1.1–10.5) and a trend of association with donor body mass index >30 and pancreas cold ischemia time greater than 12 hr. Conclusions PPFCs are associated with significant reduction in pancreas allograft survival and impact resource use. Donor age >30 years is a significant RF for their development. PPFCs associated with pancreatic fistula carry a greater risk for pancreas graft loss.

Chronic Intestinal Failure After Crohn Disease: When to Perform Transplantation

IMPORTANCE Because of the severity of disease and additional surgery, Crohn disease (CD) may result in intestinal failure (IF) and dependency on home parenteral nutrition (HPN). Defining the indication and timing for intestinal transplantation (ITx) is challenging. OBJECTIVES To determine the limitations of conventional surgery and to facilitate the decision making for transplantation. DESIGN, SETTING, AND PARTICIPANTS Data were collected prospectively and obtained by retrospective review of medical records from all patients with CD who were assessed for ITx in Oxford, United Kingdom, and Berlin, Germany, from October 10, 2003, through July 31, 2013. Patients were considered suitable for ITx if a diagnosis of irreversible IF was established and life-threatening complications under HPN were unresolvable. Twenty patients with CD and IF, established on HPN, were evaluated for ITx. The mean (SD) age at CD onset was 17.8 (9.8) years. On first diagnosis, most patients had a stricturing CD. By the time of referral, most had a combination of stricturing and fistulizing disease. INTERVENTIONS New scoring system: a modification of the American Gastroenterology Association guidelines for ITx. Modifications are related to CD-specific issues that potentially lead to a poorer outcome and are based on the findings of the study to determine the expected benefit from ITx. MAIN OUTCOMES AND MEASURES A scoring system that would alert the physician to the severity of the patients CD and trigger early referral for ITx. This system may translate into better long-term outcomes for patients with CD. In addition, the Karnofsky performance status score was used to compare pretransplantation and posttransplantation outcomes. RESULTS Ten patients underwent ITx, 4 were on the waiting list, and 4 were unavailable for follow-up. One patient was taken off the waiting list because of severe deterioration. One patient underwent conventional stricturoplasty and did not need transplantation. Among the transplant recipients, 17 (85%) had a stoma or enterocutaneous fistula, and the mean (SD) residual bowel length was 71.5 (38) cm. A total of 80% of transplant recipients had life-threatening catheter infections, and 13 (65%) had a significant decrease in the estimated glomerular filtration rate. At a mean (SD) follow-up of 27.6 (36.1) months for transplant recipients, the patient and graft survival is 80%, and their Karnofsky performance status score increased by a mean of 18.6%. CONCLUSIONS AND RELEVANCE Intestinal transplantation is a suitable treatment option for patients with CD and IF. It should be considered before any additional attempts at conventional surgery, which may cause eligible patients to miss this opportunity through perioperative complications. The suggested scoring system enables the physician to identify patients who may benefit from transplantation before HPN-associated secondary organ failure.

Solitary pancreas transplantation: a review of the UK experience over a period of 10 yr

The aim of this study was to see whether lessons could be learned from the prospectively maintained nationwide database on solitary pancreas transplantation (SPTx) performed in the UK.

Markers of malnutrition after intestinal transplantation: the role of IGF-1 and calprotectin

The objective of this study is to valuate two biomarkers that may guide nutritional assessment during follow up after intestinal transplantation. We performed a retrospective study on prospectively collected data of insulin-like growth factor-1 (IGF-1) and effluent calprotectin in patients undergoing intestinal transplantation. Optimal nutritional status (ONS) was defined by using the Malnutrition Universal Screening Tool (MUST). IGF-1 and calprotectin were correlated with ONS by Pearson correlation. Eighteen cadaveric intestinal transplants were performed over 1,650 days (median follow up 425 days, range 29–1,650 days). Mean IGF-1 and calprotectin were significantly associated with independent nutrition. Seven patients became malnourished on one or more occasions. During malnutrition the mean IGF-1 was 22 ± 14 ng/ml and calprotectin 1,597 ± 1,055 mcg/g. Mean weight during episodes of malnutrition changed from 64.77 ± 8.76 kg to 59.05 ± 8.5 kg (–8.9 ± 1.25%). Both IGF-1 and calprotectin negatively correlated with ONS (Pearson’s r, –0.612, p = 0.014). Patients broadly aligned with three groups: nutritionally replete (normal IGF-1 and normal calprotectin), nutritionally equivocal (normal or low normal IGF-1 and high calprotectin), and malnourished (low IGF-1 and high calprotectin). Patients with low IGF-1 and high calprotectin may have a benign clinical presentation. However it is in their interests to have parenteral nutrition restarted pending further investigation.

The abdominal wall transplant as a sentinel skin graft.

Purpose of reviewAbdominal wall transplantation is a technique used to achieve abdominal closure after intestinal and multivisceral transplantation. This review focuses on whether there are additional benefits for the skin component as an immune-monitoring tool. Recent findingsThe largest series of abdominal wall transplants has recently been published. Alongside the physiological advantage gained in abdominal closure, the authors describe the immunological insight that the skin component can provide and how this contributes to the management of patients. The skin appears to develop a rash with early rejection, which facilitates early systemic treatment before significant visceral rejection occurs. It can also help in cases in which there is diagnostic doubt regarding the cause of bowel dysfunction such as in instances of intestinal infection. Despite the additional immunological burden of donor tissue, there appears to be no requirement for increased immunosuppressive therapy. SummaryThe technical and immunological feasibility of abdominal wall transplantation has now been demonstrated by several centres. Skin transplanted as part of the abdominal wall or as a separate vascularized sentinel skin flap may aid in the diagnosis of rejection. This has the potential to improve graft survival and reduce immunosuppressive morbidity.

PWE-095 Serum micronutrients levels are maintained post-intestinal transplant in keeping with graft function

Introduction Chronic intestinal failure is defined by the lack of absorption of micronutrients, macronutrients or water requiring intravenous support. The absorptive capacity of the gut is determined by length of gut present in continuity, enteric adaptation and speed of transit. Frequently patients require intravenous micronutrient support. Following intestinal transplant (ITx) the graft is able to absorb both micro and macronutrients such that parenteral nutrition (PN) is no longer required. We studied transplanted patients in a single centre to assess the absorption of micronutrients. Method This was a retrospective analysis of a prospective database. Results were taken from patients being assessed for ITx, then at 3 monthly intervals, and then yearly. Data are inclusive of results either side of the specified timepoint. Data were analysed on Prism using one-way ANOVA and Tukey multiple comparisons test. Data reported as mean ±95% confidence interval. Results 34 patients received 35 transplants. Mean age was 41.9y (range 23–73). M/F: 22:14. Median follow up was 774d (range 16–3029). Indications included Crohn’s disease (7/36,19%), intra-abdominal desmoids (4/36,11%), visceral neuromyopathy (5/36,14%), vascular ischaemia (6/36,17%), radiation enteritis (2/36,6%), NET (1/34,3%), pseudomyxoma peritonii (6/36,17%) and other (5/36,13%). Zinc, folic acid, B12, Vitamin A and Vitamin D were significantly different using one way ANOVA: Zinc (p<0.0001) with significant Tukey for pre-ITx (16.9±1.07) vs. 12m (14.2±1.2,p<0.05), vs. 24m (13.5±1.5,p<0.05), vs. 36m (12.9±1.4,p<0.005) and vs. 48m (13.2±1.2,p<0.005); Folic acid (p=0.0006) with significant Tukey for pre-ITx (10.1±0.9) vs. 3m (6.6±1.0,p<0.05), vs. 6m (5.71±1.3,p<0.05); and between 3m vs. 24m (11.7±2.5,p<0.005) and 6m vs. 24m (p<0.005); B12 (p=0.0349) with significant Tukey for 6m (883.2±202.8) vs. 24m (555.8±121.3); Vitamin A (p<0.0001) with significant Tukey for pre-Tx (1.87±0.41) vs 3m (3.27±0.56,p<0.001), 3m vs. 24m (1.79±0.32,p<0.001) and vs. 48m (2.22±0.34,p<0.05), 6m (2.80±0.55) vs. 24m (p<0.05); Vitamin D (p=0.0469) without significant Tukey for any timepoints. Conclusion Observing micronutrient changes aids our understanding of transplanted graft function and nutritional intake. The reduction in zinc, folate and B12 is perhaps more physiological than clinically significant, as the levels were within the normal range and may reflect over-treatment when on PN, though it is interesting to observe folate rising back to a higher level after 6m. It is reassuring to observe that the ITx is not deleterious to micronutrient metabolism. Disclosure of Interest None Declared

Diagnostic Lessons from a Complex Case of Postintestinal Transplantation Enteropathy

Recent advances in the field of intestinal transplantation have been mitigated by the incidence of allograft rejection. In such events, early identification and appropriate timing of antirejection therapy are crucial in retaining graft function. We present the case of a patient who suffered severe postintestinal transplantation allograft enteropathy, primarily characterized by extensive mucosal ulcerations, and was refractory to all conventional therapy. This progressed as chronic rejection; however crucially this was not definitively diagnosed until allograft function had irreversibly diminished. We argue that the difficulties encountered in this case can be attributed to the inability of our current array of investigative studies and diagnostic guidelines to provide adequate clinical guidance. This case illustrates the importance of developing reliable and specific markers for guiding the diagnosis of rejection and the use of antirejection therapeutics in this rapidly evolving field of transplant surgery.

Multidisciplinary care ensures successful pregnancy following intestinal transplantation: a case report.

pregnancy following intestinal transplantation: a case report V Blackwell,* L Holdaway,* J Hogan, J Gilbert, S Sinha, G Vrakas, S Reddy, P Friend, L Mackillop, D Harrington, C Greenwood, A Vaidya, PJ Allan a Translational Gastroenterology Unit, John Radcliffe Hospital, Oxford University Hospitals NHS Trust, Oxford, UK b Oxford Transplant Centre, Churchill Hospital, Oxford University Hospitals NHS Trust, Oxford, UK c Department of Obstetrics and Gynaecology, Women’s Centre, John Radcliffe Hospital, Oxford University Hospitals NHS Trust, Oxford, UK Correspondence: Dr P Allan, Consultant Gastroenterologist, Translational Gastroenterology Unit, Oxford University Hospitals NHS Foundation Trust, Level 5, John Radcliffe Hospital, OX3 9DU, Oxford, UK. Email philip.allan@ouh.nhs.uk