Pretransplant Evaluation Research Articles

S2155 Utilizing the Pure-Vu EVS for Inpatient Colonoscopy for Patients With an LVAD: A Case Report

Introduction: Colonoscopy is considered the standard for colon cancer screening. A key factor in ensuring high quality colonoscopy is adequate colon cleansing. In hospitalized patients, bowel preparation is often challenging and inadequate cleansing is often due to patient’s inability to tolerate the preparation, slow bowel transit in the setting of immobilization and acute illnesses, and the use of motility-altering medications. Poor bowel preparation limits visualization of the colonic mucosa and can lead to incomplete colonoscopies, missed pathology, adverse events, prolonged hospital stays and increased costs. New technologies have been developed to improve bowel preparations intra-procedurally. The Pure-Vu EVS system, which is an over-the-scope irrigation and cleansing device. This case report describes a novel use of the Pure-Vu EVS system to improve inpatient colonoscopy prep. Case Description/Methods: A 58-year-old female with past medical history significant for chronic systolic heart failure, ischemic cardiomyopathy status post Left Ventricular Assist Device (LVAD) one year prior. End stage heart failure patients requiring LVAD placement routinely undergo screening colonoscopy as part of their pre-transplant evaluation, as the presence of colon cancer or advanced neoplasia could preclude heart transplantation. As part of orthotopic heart transplant evaluation she was admitted to the hospital for IV heparin bridging for screening colonoscopy. After admission, the patient was started on standard bowel prep consisting of 4L of Golytely and Dulcolax suppository. Despite completion of prep, she continued to pass sediments and prep was deemed inadequate. The patients LVAD anticoagulation had been held for the procedure and the decision was made to proceed with colonoscopy utilizing the Pure-Vu EVS device. During the procedure the clinical team utilized the Pure-Vu EVS device and performed the procedure with cardiovascular anesthesia. The Pure-Vu EVS system effectively irrigated and suctioned areas of inadequate bowel prep with sediment larger than 3.8 mm, allowing for improved visualization of the colonic mucosa. Discussion: Pure-Vu EVS allowed for us to perform a screening colonoscopy as part of orthotopic heart transplant evaluation in a patient with LVAD admitted a hospital inpatient service for heparin bridge. This case report describes one of the first cases of the utilization of this unique technology in a patient requiring inpatient screening colonoscopy with advanced heart failure.

Safety and value of pretransplant antibiotic allergy delabeling in a quaternary transplant center.

Self-reported antibiotic allergies, also known as antibiotic allergy labels, are common and may lead to worse patient outcomes. Within immunocompromized patients, antibiotic allergy labels can lead to inappropriate use of antimicrobials and may limit options for prophylactic and therapeutic options in the posttransplant period. While antibiotic allergy delabeling is considered an important aspect of antibiotic stewardship protocols, evidence and awareness of its application in transplant recipients is limited. We describe our experience with an antibiotic allergy delabeling intervention in the pretransplant evaluation period and its impact on posttransplant antimicrobial utilization. This was a retrospective analysis of patients with an antibiotic allergy label who underwent evaluation for solid organ or stem cell transplantation between 2015 and 2020. Patients included in this analysis were those who completed pretransplant antibiotic allergy delabeling through our Drug Allergy Clinic and were retained in care for 6 months after transplant. Twenty-six of 27 patients underwent pretransplant antibiotic allergy delabeling and safely received the delabeled antibiotic posttransplant. There were no reported side effects to the delabeled antibiotic within 6 months posttransplant. Specific examination of sulfonamide (sulfa)-antibiotic delabeling showed cost savings of $254 to $2910 per patient in the posttransplant period compared to the use of alternative antibiotics for prophylaxis protocol. Antibiotic allergy delabeling prior to transplant is safe, is of high value, and should be considered in the pretransplant evaluation period.More resources are needed for the development of delabeling guidelines and support for broad implementation of pretransplant antibiotic allergy delabeling programs.

Sex and gender disparity in kidney transplantation: Historical and future perspectives.

Sex and gender disparity exist in various stages of kidney transplantation. Females were found to be less likely to be referred for kidney transplant, complete pre-transplant evaluation, be placed on the waitlist, and receive a kidney transplant compared to their male counterparts. Interestingly, females comprise the majority of living kidney donors. This review explores the biological and psychosocial factors that contribute to sex and gender disparity in kidney transplantation and proposes ways to address the disparity.

Pretransplant evaluation and the risk of glucose metabolic alterations after renal transplantation: a prospective study.

Post-transplant prediabetes (PreDM) and diabetes (PTDM) are common and have an impact on cardiovascular events. We sought to investigate the pathogenesis and best approach for prediction. We prospectively studied 115 waitlisted patients from a single center without manifest diabetes. An oral glucose tolerance test (OGTT) was performed yearly until transplantation and 12 months later. Insulin secretion, insulin sensitivity (IS) and disposition index (DI) were derived from the OGTT. PreDM and PTDM were observed in 27% and 28.6% of patients, respectively. Pretransplant age, body mass index (BMI), 120 min glucose, IS, DI, and prediabetes or undiagnosed diabetes were significantly associated with these alterations. In multivariate analysis, pretransplant age [odds ratio (OR) 1.5; 95% confidence interval (CI) 1.04-2.1], BMI (OR 1.16; 95% CI 1.04-1.3) and cumulative steroids (OR 1.5; 95% CI 1.02-2.2) were predictors of PreDM or PTDM. Receiver operating characteristic curve analysis showed that pretransplant BMI and 120 min glucose had the highest area under the curve (0.72; 95% CI 0.62-0.8; and 0.69; 95% CI 0.59-0.79, respectively). The highest discrimination cut-off for BMI (≥28.5 kg/m2) and 120 min glucose (≥123.5mg/dL) yielded a similar number needed to diagnose (2.5). PreDM or PTDM develops in waitlisted patients with an ineffective insulin secretion and BMI shows a similar diagnostic capacity to OGTT. Pretransplant interventions may reduce post-transplant glucose alterations.

P6.06: The Monetary Cost of Delays in Kidney Transplantation in A Public Health Facility in a Developing Country: Kenyan Experience

Introduction: Kidney transplantation is the preferred choice of treatment for end stage kidney disease (ESKD) as it confers the recipients with better quality of life when compared with other modalities of kidney replacement therapy (KRT). The economic benefits of kidney transplantation are also superior when compared with either dialysis or conservative treatments respectively. In living kidney donations, the pre-transplant evaluation involves sequenced processes all aimed at optimizing resources to deliver a kidney transplant within the shortest time. The shortest period of a donor-recipient pair evaluation within our transplant program is three (3)months. Delays in operation for a kidney transplant attracts both direct and indirect costs with the most unavoidable being the direct cost of continued dialysis. Methods: We set up a study to establish duration of delays in certain processes with the pre-transplant evaluation for donor-recipient pairs from which we could calculate the direct cost of continued hemodialysis (HD) using a twice weekly HD model at approximately 80 USD per session as the amount at which the social insurance reimburses for HD. We considered three (3) months as the optimum and the economic-neutral duration. This was an observational retrospective study conducted at the Kenyatta National Hospital in Kenya over a five-year period between 2010 to 2014. The captured data were analysed using Statistical Package for the Social Science version 20.0. For categorical data, frequencies were calculated as numbers and percentages while for numerical data, the means and standard deviations were calculated when normally distributed while the medians and interquartile ranges were calculated for skewed data. Results: A total of 99 donor-recipient pairs who had undergone pre-transplant evaluation between 2007 – 2014 and underwent transplantation during the study period were included. The mean age was 37±13 years. Males were 73(73.7%). Sixty two (62.6%) were married and sixty five (65.7%) were in informal self-employment. The median duration taken in the kidney transplant evaluation process was 10 months (IQR 5 – 13). Only six (6) donor-recipient pairs (6.3%) were evaluated within three (3) months period. The remaining 93(93.7%) were evaluated for between four (4) and 84 months. This translated to 891 HD-months within which 7,128 sessions of HD were purchased by the social insurer. At a cost of USD 80 per HD session, this translated to USD 570,240 as being the direct cost required to maintain the patients on HD during the delayed period. Conclusion: The time taken to go through the pre-transplant evaluation process within our program is long with the cost of maintaining patients on HD presenting an enormous opportunity cost which can be reduced significantly if the pre-evaluation period is shortened to three months. Keywords: End stage kidney disease, kidney transplantation, Cost, hemodialysis.

P8.137: Bladder Evaluation in Transplant Patients: Are We Overdoing It?

Introduction: It is a common practice to perform detailed bladder evaluation(DBE) in patients awaiting transplant surgery, with previous research by some noted authors Yang(1994), Peter(2004), Antoniewicz(2015) supporting this. ESRD patients on maintenance haemodialysis for more than a year eventually become anuric. For their bladder evaluation, it becomes imperative to catheterize and fill the bladder retrogradely. Catheterization thus may need to be done as high as three times, for ultrasonography (USG), micturating cystourethrogram (MCU) and uroflowmetry (UFR). This leads to bacterial colonization in bladder and results in colonisation of the lower tract and a nidus for repeated reinfection. Aim of our study is thus to find out the necessity for detailed bladder evaluation in all patients & how low-capacity poor flow bladders fare post-operatively. Methods: We studied 80 patients retrospectively for detailed reports on bladder evaluation and their follow up till one year post transplant. Results: A very high incidence of pyelonephritis (70%) in our post- transplant patients who has undergone DBE. Additionally, some patients are still advised bladder cycling. 85%(68) of patients even with no prior history of lower urinary tract dysfunction (LUTD) or Genitourinary Tuberculosis(GUTB) had a small capacity bladder on USG and/or poor flow pre-operatively. However, in majority (90%) of them, bladder capacity and urine flow normalize as soon as urine production starts. Only a few (7 out of 68) having healthy but low capacity bladder with poor flow required some form of intervention. Conclusions: Patients who have healthy bladders prior to progressing to ESRD and becoming anuric fare well in post-transplant period as soon as urine production starts even if they are found to have small capacity, low flow in pre-transplant period. DBE in such patients can not only lead to overtreatment, waste resources but also increases infectious complications. Thus, we can omit MCU& UFR in pre transplant evaluation. Only baseline USG to measure bladder capacity and thickness is all that is required. Detailed evaluation reserved only for patients having past-history of LUTD, GUTB, or bladder dysfunction like posterior urethral valves. Thus, by carefully selecting the patient, we minimized the post-transplant pyelonephritis infectious complications to 29%. Dr. Tukaram Jamale, Professor and Head, Department of Nephrology, Seth GSMC & KEMH All Urology and Nephrology Residents.

P9.32: Excellent Outcome Quality Is Not Dependent on a High Caseload in Liver Transplantation

Background: Today’s dogma without clear evidence is that case volume correlates with patients’ outcome after liver transplantation (LT). Thus, we prospectively analyzed the outcomes in our low volume center, which is characterized with strong interdisciplinary and interprofessional concepts. Methods: Our LT program was re-organized and re-structured in 2016 including a center-embedded interdisciplinary and interprofessional team concept with new clinical standards for the peri-, intraoperative and follow-up management of patients. In parallel, routine pre-transplant histopathological evaluation of donor organs was established. Outcomes of 166 adult LTs (125 male; median age of 55.4 years [19 to 74 years]) performed between November 2016 and November 2021 was documented in a prospective database driven manner and compared with high volume centers. Kaplan-Meier method was used for long-term patient and graft survival. Results: 1-/ 5-years patient and graft survival was 95.3%/ 91.8% and 82.7% and 78.4%, respectively. The median ICU stay was 2 days [1-125 days] and the median hospital stay was 15 days [7-187 days]. Hospital readmissions were necessary within the first 30 days and 1 year after discharge in 8% and 16% of cases, respectively. Conclusion: Clearly defined standards developed within an interdisciplinary and interprofessional team concept result in best possible outcome quality of treatment after LT independent of caseload.

247.5: Magnetic Resonance Imaging of Renal Oxygen Metabolism by Means of 17-O Administration During Ex Vivo Organ Perfusion

Background: Renal normothermic machine perfusion (NMP) is a method studied for pre-transplant evaluation of kidney graft quality. This technique creates an isolated near-physiological environment by circulating a perfusion solution at body temperature with oxygen and nutrients. However, reliable ex vivo organ viability markers are still lacking. Magnetic resonance imaging (MRI) has recently been applied as a new rapid non-invasive technique to study renal viability ex vivo. Oxygen-17 (17O) offers a novel sensitive assessment of oxidative metabolism. In our MRI compatible perfusion setup, we aimed to study oxygen metabolism during NMP. Methods: Three viable porcine kidneys were retrieved at a slaughterhouse and preserved by oxygenated hypothermic machine perfusion. In addition, one discarded human kidney was shipped to our center in static cold storage. Subsequently each kidney was perfused for 4 hours at 37°C inside a clinical 3T MRI scanner. Blood gas, glucose, and electrolytes were periodically monitored. Anatomical T2-weighted images and T2* maps were obtained using a 1H 18Ch-bodyflex coil and dynamic radial 17O MR images were acquired using a 17O Tx/Rx loop coil and a 17O 3D-UTE sequence. The 17O perfusion protocol consisted of 4 minutes of deoxygenation with nitrogen gas, 8 minutes of 70%-enriched 17O2 gas infusion at 0.1L/min, and 20 minutes of subsequent carbogen (95% O2/ 5% CO2) oxygenation. 17O-magnitude data was analyzed dynamically over time. To study the 17O-related global signal change, a region of interest was defined in the anatomical T2-weighted images and co-registered to the dynamic 17O-magnitude data. Results: Porcine kidneys showed homogenous perfusion with increased H217O-concentration in the medulla and decreased concentration in the cortex. The discarded human kidney demonstrated a focused concentration in the medial side of the lower pole with little to no signal intensity in the upper pole and the majority of the cortex, which was consistent with its reason for discard (wide cist in the lateral pole). Six minutes after administration of 17O2-gas, a rapid H217O signal increase was observed until minute 20 of the dynamic acquisition, where saturation was reached and the signal plateaued. Overall, an enhancement of 16% between the first and last data point was measured. Conclusion: In these pilot experiments, we were able to quantify the regional production of H217O in time, both in porcine and human kidneys. The slope of occurrence of H217O may be an interesting ex vivo organ viability biomarker, immediately related to the rate of oxidative metabolism in the organ and hence organ quality. As the kidney is in an ex vivo setting, any increase in H217O-concentration must be the direct result of metabolism within the organ. The current setup has great potential for investigating renal oxygen metabolism ex vivo. NUKEM Isotopes GmbH, Alzenau, Germany. Department of Radiology, University Medical Center Freiburg, Freiburg, Germany.

P11.04: Evolution and Impact of Regional Investment Projects on Public Offer of Organ Procurement and Transplantation in Argentina: An Analysis From 2008 to 2021

Introduction: Argentine shows accessibility difficulties within vulnerable populations due to socioeconomic and geographical reasons. To ameliorate this problem, in 1993 it was created the Solidarity Fund for Transplants (FST) at the INCUCAI. The aim of this Fund was to create and/or strength the public transplant activity, implement financial assistance for facilitating the access to waitlists, the organ, tissues and cells transplant, development and strength cell and/or tissue banks, pre-transplant evaluation centers and histocompatibility laboratories. Herein, we evaluated the magnitude and evolution of the strengthening of the network established from the FST, through the funding of Provincial Investment Projects (PPI). Methods: This is a retrospective descriptive study from 2008 to 2021. The variables analyzed (types of projects and amounts transferred or executed) were classified by year, province and region. Data was taken from the Resource Management Unit, Coordination of the FST and the Unit of Special Programs (USP) and the INCUCAI administration. In order to compare the investments, they were dollarized according to the price of the dollar at the time of transferring the funds. Results: Results: the FST managed and financed 102 projects. The analysis showed that, except for 2018 and 2019, every year investments projects were managed, being the highest in 2021, followed by 2012 and 2013.The largest number of projects coincides with the start-up and activity of the USP, which has generated investment guides for projects and has provided technical assistance to facilitate and promote the presentation of projects. The largest amount transferred in US dollars was to 2010 (2,731,665 in 5 projects), followed by 2013 (2,731,248 in 11 projects) and 2014 (2,179,979 in 6 projects).However, the highest investment on average per project (546,333 US dollars in 5 projects) was in 2010. Regarding the type of project, there was greater investment in the generation of services, infrastructure and jurisdictional strengthening in the beginning, while for the last years reinforcements were observed in equipment, procurement and transplantation. The Central region concentrates the largest number of PPIs, followed by Northeast and NOA. The latter received the largest transfer per project on average. Conclusions: The PPIs strengthened the network and supplies of the establishments of the state public sector. There was an improvement in the installed capacity for organ procurement and transplantation in all regions of the country but unevenly distributed. Seven jurisdictions did not submit PPIs to be financed, suggesting that it will be necessary a more directed actions for those provinces. Finally, UCPE activities shows a positive impact on the generation of PPIs, which will tend to reduce waitlists for transplants and an improvement in the accessibility of the most vulnerable populations.

340.6: Variability in Workup and Eligibility Criteria for Adult Kidney Transplantation Among Canadian Transplant Centres

Introduction: All potential kidney transplant recipients undergo rigorous evaluation to rule out or ensure appropriate treatment of conditions that may increase risk of post-transplant complications, but specific recommendations regarding workup and kidney transplant candidacy vary across published guidelines. We assessed current pre-transplant evaluation practices and eligibility criteria for adult kidney transplantation across Canada to elucidate differences in guideline interpretation and identify areas of most uncertainty. Methods: We compared published guidelines on kidney transplant workup and eligibility in order to create a focused digital survey that included both undisputed and controversial domains. The survey was divided into: referral process, history/physical exam, multidisciplinary assessments, laboratory/imaging, and contraindications. Given the many cancers and different staging for each, malignancy-related inquiries were simplified. The medical directors of all 18 Canadian adult kidney transplant programs were invited to complete the survey. We defined consensus and uncertainty, respectively, as >90% and <65% agreement between centers. Results: Survey completion rate was 78% (14/18). There was consensus on mandatory pre-transplant viral serology testing, tuberculosis screening, and dental evaluation, while cardiac evaluation protocols varied considerably. Of 28 questioned conditions, 6 were considered absolute contraindications by >90% of centers (active bacterial infection/malignancy, non-healing ulcer, COVID-19, severe lung/liver disease). Moderate uncertainty existed for: medication non-adherence (57%), symptomatic heart failure (50%), recent myocardial infarction (57%), and frailty (35%). Other parameters demonstrating wide variability included latent tuberculosis treatment protocols, and exclusion thresholds for parathyroid hormone, body mass index, left ventricular ejection fraction, and blood pressure. Centers used several guidelines to determine eligibility for patients with treated cancer. Conclusion: There is marked variability in evaluation requirements and eligibility criteria for kidney transplantation across Canada. National harmonization of evaluation processes and eligibility criteria may help to ensure more equitable and transparent access to kidney transplantation for Canadian patients with end-stage kidney disease.

An enhanced level of VCAM in transplant preservation fluid is an independent predictor of early kidney allograft dysfunction.

BackgroundWe aimed to evaluate whether donor-related inflammatory markers found in kidney transplant preservation fluid can associate with early development of kidney allograft dysfunction.MethodsOur prospective study enrolled 74 consecutive donated organs who underwent kidney transplantation in our center between September 2020 and June 2021. Kidneys from 27 standard criteria donors were allocated to static cold storage and kidneys from 47 extended criteria donors to hypothermic machine perfusion. ELISA assessment of inflammatory biomarkers (IL-6, IL6-R, ICAM, VCAM, TNFα, IFN-g, CXCL1 and Fractalkine) was analyzed in view of a primary endpoint defined as the occurrence of delayed graft function or slow graft function during the first week following transplantation.ResultsSoluble VCAM levels measured in transplant conservation fluid were significantly associated with recipient serum creatinine on day 7. Multivariate stepwise logistic regression analysis identified VCAM as an independent non-invasive predictor of early graft dysfunction, both at 1 week (OR: 3.57, p = .04, 95% CI: 1.06-12.03) and 3 Months (OR: 4.039, p = .034, 95% CI: 1.11-14.73) after transplant surgery.ConclusionsThis prospective pilot study suggests that pre-transplant evaluation of VCAM levels could constitute a valuable indicator of transplant health and identify the VCAM-CD49d pathway as a target to limit donor-related vascular injury of marginal transplants.

Pretransplant Evaluation and Liver Transplantation Outcome in PBC Patients.

Primary biliary cholangitis (PBC) is an autoimmune chronic cholestatic liver disease characterized by progressive cholangiocyte and bile duct destruction leading to fibrosis and finally to liver cirrhosis. The presence of disease-specific serological antimitochondrial antibody (AMA) together with elevated alkaline phosphatase (ALP) as a biomarker of cholestasis is sufficient for diagnosis. Ursodeoxycholic acid (UDCA) is the first treatment option for PBC. Up to 40% of patients have an incomplete response to therapy, and over time disease progresses to liver cirrhosis. Several risk scores are proposed for better evaluation of patients before and during treatment to stratify patients at increased risk of disease progression. GLOBE score and UK PBC risk score are used for the evaluation of UDCA treatment and Mayo risk score for transplant-free survival. Liver transplantation (LT) is the only treatment option for end-stage liver disease. More than 10 years after LT, 40% of patients experience recurrence of the disease. A liver biopsy is required to establish rPBC (recurrent primary biliary cholangitis). The only treatment option for rPBC is UDCA, and data show biochemical and clinical improvement, plus potential beneficial effects for use after transplantation for the prevention of rPBC development. Additional studies are required to assess the full impact of rPBC on graft and recipient survival and for treatment options for rPBC.

The pharmacogenetics of mycophenolate mofetil in Tunisian renal transplant patients.

Aim: The effects of variants in IMPDH, UGT1A9, UGT1A8, UGT2B7 and SLCO1B1 genes on the efficacy and safety of mycophenolate mofetil (MMF) in the Tunisian population were investigated. Materials & methods: A total of245 kidney transplant patients being treated with MMF wererecruited and cotreated with cyclosporine or tacrolimus. Genotyping was performed using thepolymerase chain reaction-restriction fragment length polymorphismmethod. MMF, cyclosporine and tacrolimus trough levels were measured by immunoassay. The AUC (AUC0-12hMPA) was estimated by a Bayesian method. Results: In the tacrolimus-treated group, anemia and diarrhea were associated with the UGT1A9-98C and UGT1A9-275T alleles, respectively (p<0.05). In the cyclosporine-treated group, leukopenia was associated with theSLCO1B1-521T allele (p<0.05). Both groups had an increased risk of rejection (p<0.05) associated with the variant alleles of IMPDH2-3757T>C, UGT1A9-2152C>T and UGT1A9-275C>A and the common allele of SLCO1B1-388A>G. However, no significant association was foundbetween the studied genotypes and AUC0-12hMPA or cotreatment levels. Conclusion: The results constitute preliminary evidence for the inclusion of the pharmacogenetics of MMF in kidney pretransplantation evaluations.

New-onset Obesity After Lung Transplantation: Incidence, Risk Factors, and Clinical Outcomes.

Lung transplant (LTx) recipients who gain weight after transplantation may experience an upward shift in body mass index (BMI) that places them in the obese category. The incidence, risk factors, and impact on metabolic health and mortality of new-onset obesity have not been documented in the LTx setting. This single-center retrospective study included 564 LTx recipients. Individuals were stratified according to their BMI trajectories from pretransplant evaluation up to 10 y posttransplant. New-onset obesity was defined as a pretransplant BMI <30 kg/m 2 and posttransplant BMI >30 kg/m 2 . The incidence, risk factors, and posttransplant diabetes mellitus, metabolic syndrome, and mortality of recipients with new-onset obesity were compared with those of nonobese (BMI <30 kg/m 2 , pre/post-LTx), consistently obese (BMI >30 kg/m 2 , pre/post-LTx), and obese recipients with weight loss (BMI >30 kg/m 2 pre-LTx, BMI <30 kg/m 2 post-LTx). We found that 14% of recipients developed obesity after transplantation. Overweight individuals (odds ratio [OR]: 9.01; 95% confidence interval [CI] [4.86-16.69]; P < 0.001) and candidates with chronic obstructive pulmonary disease (OR: 6.93; 95% CI [2.30-20.85]; P = 0.001) and other diagnoses (OR: 4.28; 95% CI [1.22-14.98]; P = 0.023) were at greater risk. Multivariable regression analysis showed that new-onset obesity was associated with a greater risk of metabolic syndrome (hazard ratio: 1.70; 95% CI [1.17-2.46]; P = 0.005), but not of posttransplant diabetes mellitus, than nonobesity. Recipients with new-onset obesity had a survival comparable to that of consistently obese individuals. A greater understanding of the multifaceted nature of post-LTx obesity may lead to interventions that are better tailored to the characteristics of these individuals.

Ethical considerations during a pioneering surgical procedure: porcine cardiac xenotransplantation.

Preclinical advances in life-sustaining porcine cardiac xenotransplantation from donor pigs to baboons have paved the way for the performance of porcine cardiac xenotransplantation in a human. This procedure was performed with emergency use authorisation granted by the United States Food and Drug Administration under the umbrella of investigational new drug use on compassionate grounds. The patient was denied candidacy for durable mechanical circulatory support and heart transplantation as a result of non-adherence to medical advice. Successful porcine cardiac xenotransplantation in humans will significantly increase the availability of potential donor organs for long-term management of end-stage heart failure. Human porcine cardiac xenotransplantation is associated with ethical conflicts encompassing multiple ethical principles which are not mutually exclusive and are sometimes conflicting. This article focuses on some of the ethical conflicts encountered in relation to the use of mechanical circulatory support, pretransplant evaluation, shared decision making during informed consent, infectious disease risk, preclinical and clinical testing, and the role of regulatory bodies during performance of the first human porcine cardiac xenotransplantation. An increase in human trials of xenotransplantation procedures is imminent. Potential ethical conflicts associated with xenotransplantation should be addressed appropriately.

Applications of neural networks in liver transplantation

The use of neural networks as a cutting-edge technique in the medical field has drawn considerable attention. Neural network models “learn” from a large amount of data and then find corresponding clinical patterns that are challenging for clinicians to recognize. In this study, we focus on liver transplantation, which is an effective treatment for end-stage liver diseases. The management before and after liver transplantation produces a massive quantity of medical data, which can be fully processed by neural networks. We describe recent progress in the clinical application of neural networks to liver transplantation in five respects: pre-transplantation evaluation of the donor and recipient , recipient outcome prediction, allocation system development, operation monitoring, and post-transplantation complication prediction . This review provides clinicians and researchers with a description of forefront applications of neural networks in the field of liver transplantation and discusses prospects and pitfalls.

Frailty in kidney transplantation: a review on its evaluation, variation and long-term impact.

The problem of frailty in kidney transplantation is an increasingly discussed topic in the transplant field, partially also generated by the multiple comorbidities by which these patients are affected. The criteria currently used to establish the presence and degree of frailty can be rapidly assessed in clinical practice, even in patients with chronic kidney disease (CKD). The main objectives of this work are: (i) to describe the method of evaluation and the impact that frailty has in patients affected by CKD, (ii) to explore how frailty should be studied in the pre-transplant evaluation, (iii) how frailty changes after a transplant and (iv) the impact frailty has over the long term on the survival of renal transplant patients.

Paediatric kidney transplantation: Towards a framework for pretransplant urological evaluation.

The role of the urologist in paediatric kidney transplantation has evolved alongside advances in management for the various causes of end-stage kidney disease. Improvements in antenatal intervention and postnatal care have seen children with increasingly complex urological anomalies survive until transplant. Once solely responsible for the oversight of a child's surgical care, the paediatric urologist now works within a multidisciplinary transplant team, alongside transplant surgeons, paediatric nephrologists, transplant coordinators, psychologists, social workers, and transitional care specialists. We sought to identify available pretransplant evaluation frameworks to guide urological preparation and decision-making. Drawing from available evidence and reflecting on multi-institutional experience, we propose a streamlined approach to urologic assessment, which recognises that optimal transplant outcomes in this heterogenous cohort require lower urinary tract dysfunction to be carefully defined preoperatively.

Impact of catch-up vaccinations on anti-HLA antibody response in pediatric kidney transplant candidates.

Efforts have been concentrated on improving vaccination administration during the pretransplant evaluation period. However, concern for human leukocyte antigen (HLA) sensitization subsequent to vaccination exists. A retrospective review of pediatric kidney transplant candidates (PKTCs) ≤18 years old who had received vaccinations between February 1, 2017 and November 30, 2019 was conducted. Emergence of de novo anti-HLA antibody (HLA-Ab) 3-4 weeks postvaccinations detected by the Luminex single antigen bead assay (SAB) was evaluated. Outcomes assessed included change in the HLA-Ab mean fluorescence intensity (MFI) ≥25% from baseline, and change in preexisting HLA-Ab MFI strength, categorized as weak: 1000-2999; moderate: 3000-9999; and strong: ≥10 000. Sixty vaccinations were administered to 14 patients. Forty-one potential de novo HLA-Ab were detected in five patients. After additional antibody panel testing, 5/41 potential de novo HLA-Ab were determined to be HLA specific; the remaining 36 were deemed nonspecific. The 5 de novo HLA-Ab were observed in three patients and were deemed weak antibody (Ab). Median MFI showed a significant increase for nonspecific Ab, but not de novo HLA-Ab. Median MFI values were deemed transient at 7-10 week follow-up. No HLA-donor-specific Ab developed posttransplant in the patients who developed de novo HLA-Ab. Vaccination resulted in a transient increase in non-HLA-specific Ab. The majority of responses were non-HLA specific, hypothesized to be related to denatured antigens on single antigen beads. These data suggest limited clinical impact of vaccinations on the emergence of de novo HLA-Ab.

MO719: Contrast Nephropathy in Peritoneal Dialysis Patients: A Single-Center Experience

Abstract BACKGROUND AND AIMS Peritoneal dialysis (PD) patients are frequently exposed to contrast media through contrast-enhanced computed tomography (CT) and/or coronary angiography, which may be used as diagnostic tools or as part of pretransplant evaluation. However, the risk of contrast nephropathy frequently limits the use of these imaging techniques. The authors aim to evaluate the loss of kidney function after contrasted examination in PD patients. METHOD We performed an observational retrospective study in a population of patients with end-stage kidney disease on PD. All patients included had performed an ionized radiation-imaging exam (CT or coronary angiography), with or without contrast media. In patients who performed more than one of the aforementioned exams, only the first one was considered. Demographic and laboratory data including kidney function and dialysis dose before and after the imaging exams were collected. We divided the population into two groups (no contrast use versus contrast use) and compared them using Mann–Whitney test or Chi square. A survival analysis was performed (time to exam; outcome—loss of renal function; predictor—contrast use). RESULTS A population of 41 patients in PD, 26 in automated PD (63.4%), with a dialysis vintage of 29 (17–38) months were included in this analysis. The median time since starting PD and the exam was 15 (5–20) months, and contrast was used in 21 exams (51.2%). Five patients underwent coronary angiography and 16 were submitted to contrast-enhanced CT. Only two patients performed contrast nephropathy prophylaxis before contrast exposure. In univariate analysis, we found no difference between renal residual function, KT/v and creatinine clearance before and after the imaging exam, irrespective of contrast use. After the diagnostic exam, 19 patients lost residual renal function [median GFR 1 (1–2) mL/min/1.73 m2], and the group of patients who did not use contrast were the most affected ones; however, there was no statistical significance difference between the two groups (P = 0.08). Since we found a significant difference in the time to imaging exam between the two studied groups, we performed a survival analysis, and the use of contrast was associated with preservation of renal function (P = 0.02). A multivariate Cox analysis with age, Charlson index, GFRe pre-exam, diabetes, use of RAASi, beta-blocker, loop diuretic and spironolactone as potential confounders showed that use of contrast was not associated with loss of renal function in PD patients. CONCLUSION Our study showed that contrast nephropathy is not frequent in PD patients and that we can allow contrast media (low or iso-osmolal) as it was not associated with loss of residual renal function.