1-year Graft Survival Research Articles

Outcomes of liver transplant recipients with high MELD scores: an experience from a Canadian centre.

Background:The frequency with which patients with high Model for End-Stage Liver Disease (MELD) scores undergo liver transplantation has been increasing. Canadian literature regarding the outcomes of liver transplantation in recipients with high MELD scores is limited. The primary objective of this study was to assess patient and graft survival among recipients with high (> 35) and low (≤ 35) MELD scores. Secondary objectives were to potentially identify independent predictors of graft failure and patient mortality.Methods:We conducted a retrospective chart review of patients undergoing liver transplantation at a single Canadian centre from 2012 to 2017.Results:A total of 332 patients were included in the study: 280 patients had a MELD score of 35 or lower, and 52 had a MELD score above 35. Patients with high MELD scores had higher rates of pretransplant acute kidney injury and dialysis (p < 0.001), admission to the intensive care unit (ICU) or intubation (p < 0.001), intraoperative blood product transfusions (p < 0.001) and post-transplantation acute kidney injury and dialysis (p < 0.001), as well as longer ICU (p < 0.001) and hospital stays (p = 0.002). One- and 3-year patient survival in recipients with MELD scores of 35 or lower was 93.1% and 84.9% versus 85.0% and 80.0% in recipients with MELD scores above 35 (p = 0.37). One- and 3-year graft survival in recipients with MELD scores of 35 or lower was 91.7% and 90.9% versus 77.2% and 72.8% in recipients with MELD scores above 35 (p < 0.001). Prior liver transplant was an independent predictor of patient mortality, and no independent predictors of graft failure were identified. When MELD was replaced with D-MELD (donor age × recipient MELD), it predicted graft failure but not patient survival.Conclusion:No difference in patient mortality was found between MELD groups. Graft survival was significantly lower in recipients with MELD scores above 35. D-MELD may potentially be used as an adjunct in determining risk of graft failure in recipients with high MELD scores.

Antithrombin supplementation for prevention of vascular thrombosis after pediatric liver transplantation

AimsAfter liver transplantation (LT), synthesis of coagulation factors by the graft recovers faster for pro thrombotic than anti thrombotic factors, resulting in a potential pro thrombotic imbalance. We studied the thrombotic and hemorrhagic complications in our pediatric LT series, providing supplementation of fresh frozen plasma (FFP) and/or antithrombin (AT) in the prophylactic antithrombotic regimen. MethodsThis was a retrospective observational single center study. All isolated pediatric LTs performed between 1/11/2009 and 31/12/2019 (n = 181) were included. Postoperatively, in addition to low molecular weight heparin, 22 patients (12%) received FFP (10 ml/kg twice daily for 10 days), 27 patients (15%) were given FFP (reduced duration) and AT (50–100 IU/kg/day if AT activity remained <70%), and 132 (73%) received AT only. Complications, outcome, and coagulation profiles in postoperative days 0–10 were analyzed. ResultsIn all three treatment groups, AT activity normalized by day 4 while prothrombin remained <70% of normal until day 9. Hepatic artery thrombosis (HAT), portal vein thrombosis (PVT), and hemorrhagic complications occurred in 2.8%, 3.3%, and 3.9% of LTs. One- and 5-year patient and graft survival were 88% (±2.4% Standard Error) and 84% (±2.5%), and 86% (±2.6%) and 84% (±2.7%), respectively, without difference between groups. HAT were associated with low AT on days 0 and 1, and PVT with low AT on day 0. ConclusionsLow antithrombin activity after LT was associated with postoperative thromboses. FFP and/or AT supplementation allowed early normalization of AT activity, while thrombotic or hemorrhagic complications were rare, suggesting efficient and safe management of post-LT coagulopathy.

Post-transplant Diabetes Mellitus: What Physicians Need to Know.

Post-transplant diabetes mellitus (PTDM) is a common problem among solid organ transplant recipients contributing to morbidity and affecting patient as well as graft survival adversely. It can occur at any period following transplantation, but maximum incidence is observed in the first few months, with a second peak after a few years after transplantation. The pathogenesis is complex and poorly understood, however, it is associated with both dysfunctional beta-cells and insulin resistance. Both nonpharmacologic and antidiabetic therapies are important for adequate glycemic control. This point of view article provides a short review on PTDM in solid organ transplantation (SOT) recipients from a general physician's perspective.

In situ normothermic regional perfusion versus ex situ normothermic machine perfusion in liver transplantation from donation after circulatory death.

In situ normothermic regional perfusion (NRP) and ex situ normothermic machine perfusion (NMP) aim to improve the outcomes of liver transplantation (LT) using controlled donation after circulatory death (cDCD). NRP and NMP have not yet been compared directly. In this international observational study, outcomes of LT performed between 2015 and 2019 for organs procured from cDCD donors subjected to NRP or NMP commenced at the donor center were compared using propensity score matching (PSM). Of the 224 cDCD donations in the NRP cohort that proceeded to asystole, 193 livers were procured, resulting in 157 transplants. In the NMP cohort, perfusion was commenced in all 40 cases and resulted in 34 transplants (use rates: 70% vs. 85% [p=0.052], respectively). After PSM, 34 NMP liver recipients were matched with 68 NRP liver recipients. The two cohorts were similar for donor functional warm ischemia time (21 min after NRP vs. 20 min after NMP; p=0.17), UK-Donation After Circulatory Death risk score (5 vs. 5 points; p=0.38), and laboratory Model for End-Stage Liver Disease scores (12 vs. 12 points; p=0.83). The incidence of nonanastomotic biliary strictures (1.5% vs. 2.9%; p > 0.99), early allograft dysfunction (20.6% vs. 8.8%; p=0.13), and 30-day graft loss (4.4% vs. 8.8%; p=0.40) were similar, although peak posttransplant aspartate aminotransferase levels were higher in the NRP cohort (872 vs. 344 IU/L; p < 0.001). NRP livers were more frequently allocated to recipients suffering from hepatocellular carcinoma (HCC; 60.3% vs. 20.6%; p < 0.001). HCC-censored 2-year graft and patient survival rates were 91.5% versus 88.2% (p=0.52) and 97.9% versus 94.1% (p=0.25) after NRP and NMP, respectively. Both perfusion techniques achieved similar outcomes and appeared to match benchmarks expected for donation after brain death livers. This study may inform the design of a definitive trial.

Children undergoing early liver re-transplantation for primary non-function have improved survival.

Primary non-function (PNF) in the early post-LT period in children leads to prolonged hospitalization, high graft loss, and significant mortality. However, there is a paucity of data available on the natural history of children relisted for LT due to PNF, including those who recover graft function and survive with their original allograft. We interrogated the United Network of Organ Sharing (UNOS) database for pediatric LT recipients who were relisted with a primary diagnosis of PNF from 2000 to 2020. Patients >21-year-old and multiple organ transplants were excluded. Logistic regression and Cox proportional hazard models were employed to identify risk factors for early re-transplantation (within 30 days of relisting) and mortality after adjusting for baseline clinical characteristics. One hundred and eight patients were relisted for LT for PNF during the study period. Twenty-five patients survived beyond 30 days from relisting with their original LT, 76 underwent early re-transplantation, and 7 did not survive. Having a high-risk EBV mismatch (OR 2.03, 95% CI 0.66-6.27) and an elevated donor serum creatinine (OR: 2.19, 95% CI 0.54-8.84) were associated with increased odds of a patient requiring early re-transplantation. Donor characteristics including age, final total bilirubin, final AST/ALT, and final serum sodium, as well as vasopressor use prior to procurement, were not associated with increased odds of early re-transplantation (p> 0.05). Operative characteristics including allograft type and cold-ischemia time were also not associated with early re-transplantation (p> 0.05). Patients undergoing early re-transplantation showed a trend toward improved 1-year graft survival (69% vs 55%, p= 0.24). On multivariable Cox proportional hazards modeling, early re-transplantation was associated with reduced risk of overall patient mortality compared to those who survived with their original LT (HR 0.27, 95% CI 0.12-0.67). Early re-transplantation for PNF is associated with improved patient survival compared with patients who survive with their original LT.

Does utilization of heart machine perfusion for donation after cardiac death transplantation affect outcomes of other abdominal transplanted organs?

Machine perfusion of heart for donation after circulatory death (DCD) is being increasingly utilized. Current protocols for utilizing heart DCD's machine perfusion might prolong donor warm ischemic time for nonheart organs. The aim of this study was to analyze the effects of utilizing heart machine perfusion on liver and kidney transplants from the same donor. We analyzed data of DCD donors from the United Network for Organ Sharing (UNOS) from January-2020 to September-2021 among two groups: donors with heart machine perfusion (HM) and without heart machine perfusion (NHM). Propensity score (PS) matching was performed to compare the short-term outcomes of liver and kidney transplants between two groups. Total of 102 liver and 319 kidney transplants were performed using organs from donors with HM. After PS matching, no statistically significant difference was seen in 1-year graft survival (GS) for both liver and kidney transplants between two groups (liver HM 90.6% vs. NHM 90.2%, p=.47; kidney HM 95.2% vs. NHM 92.9%, p=.40). There was no difference in the delayed graft function (DGF) rates in kidney transplantation (KT) (HM 42% vs. NHM 35%, p=.062). Utilization of heart machine perfusion in DCD donors had no significant impact on 1-year outcomes of liver and kidney transplantation.

Kidney Retransplantation after Graft Failure: Variables Influencing Long-Term Survival.

Background There is an increasing demand for kidney retransplantation. Most studies report inferior outcomes compared to primary transplantation, consequently feeding an ethical dilemma in the context of chronic organ shortage. Objective To assess variables influencing long-term graft survival after kidney retransplantation. Material and Methods. All patients transplanted at our center between 2000 and 2016 were analyzed retrospectively. Survival was estimated with the Kaplan–Meier method, and risk factors were identified using multiple Cox regression. Results We performed 1,376 primary kidney transplantations and 222 retransplantations. The rate of retransplantation was 67.8% after the first graft loss, with a comparable 10-year graft survival compared to primary transplantation (67% vs. 64%, p=0.104) but an inferior graft survival thereafter (log-rank p=0.026). Independent risk factors for graft survival in retransplantation were age ≥ 50 years, time on dialysis ≥1 year, previous graft survival <2 years, ≥1 mild comorbidity in the Charlson–Deyo index, active smoking, and life-threatening complications (Clavien–Dindo grade IV) at first transplantation. Conclusion Graft survival is comparable for first and second kidney transplantation within the first 10 years. Risk factors for poor outcomes after retransplantation are previous graft survival, dialysis time after graft failure, recipient age, comorbidities, and smoking. Patients with transplant failure should have access to retransplantation as early as possible.

Textbook Outcome as a Quality Metric in Living and Deceased Donor Kidney Transplantation.

BACKGROUND:Quality in kidney transplantation is measured using 1-year patient and graft survival. Because 1-year patient and graft survival exceed 95%, this metric fails to measure a spectrum of quality. Textbook outcomes (TO) are a composite quality metric offering greater depth and resolution. We studied TO after living donor (LD) and deceased donor (DD) kidney transplantation.STUDY DESIGN:United Network for Organ Sharing data for 69,165 transplant recipients between 2013 and 2017 were analyzed. TO was defined as patient and graft survival of 1 year or greater, 1-year glomerular filtration rate of greater than 40 mL/min, absence of delayed graft function, length of stay of 5 days or less, no readmissions during the first 6 months, and no episodes of rejection during the first year after transplantation. Bivariate analysis identified characteristics associated with TO, and covariates were incorporated into multivariable models. Five-year conditional survival was measured, and center TO rates were corrected for case complexity to allow center-level comparisons.RESULTS:The national average TO rates were 54.1% and 31.7% for LD and DD transplant recipients. The hazard ratio for death at 5 years for recipients who did not experience TO was 1.92 (95% CI 1.68 to 2.18, p ≤ 0.0001) for LD transplant recipients and 2.08 (95% CI 1.93 to 2.24, p ≤ 0.0001) for DD transplant recipients. Center-level comparisons identify 18% and 24% of centers under-performing in LD and DD transplantation. High rates of TO do not correlate with transplantation center volume.CONCLUSION:Kidney transplant recipients who experience TO have superior long-term survival. Textbook outcomes add value to the current standards of 1-year patient and graft survival.

Analysis of Volatile Anesthetic-Induced Organ Protection in Simultaneous Pancreas-Kidney Transplantation.

Background: Despite recent advances in surgical procedures and immunosuppressive regimes, early pancreatic graft dysfunction, mainly specified as ischemia–reperfusion injury (IRI)—Remains a common cause of pancreas graft failure with potentially worse outcomes in simultaneous pancreas-kidney transplantation (SPKT). Anesthetic conditioning is a widely described strategy to attenuate IRI and facilitate graft protection. Here, we investigate the effects of different volatile anesthetics (VAs) on early IRI-associated posttransplant clinical outcomes as well as graft function and outcome in SPKT recipients. Methods: Medical data of 105 patients undergoing SPKT between 1998–2018 were retrospectively analyzed and stratified according to the used VAs. The primary study endpoint was the association and effect of VAs on pancreas allograft failure following SPKT; secondary endpoint analyses included “IRI- associated posttransplant clinical outcome” as well as long-term graft function and outcome. Additionally, peak serum levels of C-reactive protein (CRP) and lipase during the first 72 h after SPKT were determined and used as further markers for “pancreatic IRI” and graft injury. Typical clinicopathological characteristics and postoperative outcomes such as early graft outcome and long-term function were analyzed. Results: Of the 105 included patients in this study three VAs were used: isoflurane (n = 58 patients; 55%), sevoflurane (n = 22 patients; 21%), and desflurane (n = 25 patients, 24%). Donor and recipient characteristics were comparable between both groups. Early graft loss within 3 months (24% versus 5% versus 8%, p = 0.04) as well as IRI-associated postoperative clinical complications (pancreatitis: 21% versus 5% versus 5%, p = 0.04; vascular thrombosis: 13% versus 0% versus 5%; p = 0.09) occurred more frequently in the Isoflurane group compared with the sevoflurane and desflurane groups. Anesthesia with sevoflurane resulted in the lowest serum peak levels of lipase and CRP during the first 3 days after transplantation, followed by desflurane and isoflurane (p = 0.039 and p = 0.001, respectively). There was no difference with regard to 10-year pancreas graft survival as well as endocrine/metabolic function among all three VA groups. Multivariate analysis revealed the choice of VAs as an independent prognostic factor for graft failure three months after SPKT (HR 0.38, 95%CI: 0.17–0.84; p = 0.029). Conclusions: In our study, sevoflurane and desflurane were associated with significantly increased early graft survival as well as decreased IRI-associated post-transplant clinical outcomes when compared with the isoflurane group and should be the focus of future clinical studies evaluating the positive effects of different VA agents in patients receiving SPKT.

Machine Learning to Analyze Factors Associated With Ten-Year Graft Survival of Keratoplasty for Cornea Endothelial Disease.

PurposeMachine learning analysis of factors associated with 10-year graft survival of Descemet stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PK) in Asian eyes.MethodsProspective study of donor characteristics, clinical outcomes and complications from consecutive patients (n = 1,335) who underwent DSAEK (946 eyes) or PK (389 eyes) for Fuchs’ endothelial dystrophy (FED) or bullous keratopathy (BK) were analyzed. Random survival forests (RSF) analysis using the highest variable importance (VIMP) factors were determined to develop the optimal Cox proportional hazards regression model. Main outcome measure was 10-year graft survival with RSF analysis of factors associated with graft failure.ResultsMean age was 68 ± 11 years, 47.6% male, in our predominantly Chinese (76.6%) Asian cohort, with more BK compared to FED (62.2 vs. 37.8%, P < 0.001). Overall 10-year survival for DSAEK was superior to PK (73.6 vs. 50.9%, log-rank P < 0.001). RSF based on VIMP (best Harrell C statistic: 0.701) with multivariable modeling revealed that BK (HR:2.84, 95%CI:1.89–4.26; P < 0.001), PK (HR: 1.64, 95%CI:1.19–2.27; P = 0.002), male recipients (HR:1.75, 95%CI:1.31–2.34; P < 0.001) and poor pre-operative visual acuity (HR: 1.60, 95%CI:1.15–2.22, P = 0.005) were associated with graft failure. Ten-year cumulative incidence of complications such as immune-mediated graft rejection (P < 0.001), epitheliopathy (P < 0.001), and wound dehiscence (P = 0.002) were greater in the PK compared to the DSAEK group.ConclusionIn our study, RSF combined with Cox regression was superior to traditional regression techniques alone in analyzing a large number of high-dimensional factors associated with 10-year corneal graft survival in Asian eyes with cornea endothelial disease.

113-OR: The Best Insulin Delivery System Remains a Human Pancreas

Purpose: Patients referred for pancreas transplantation represent a subset of difficult to treat diabetics, who may have clinical factors preventing them from achieving a goal Hgb A1C of ≤7%. Advanced insulin delivery systems with continuous glucose monitor (CGM) have been developed to offer less invasive treatment options in this population. We wanted to see how pancreas transplant performed compared to alternative modalities. Methods: We conducted a retrospective review of pancreas transplantation at our institution from January 1, 20 through August 1, 2021. All patients were ≥18 years who underwent either simultaneous kidney pancreas (SPK) , pancreas after kidney (PAK) , or pancreas transplant alone (PTA) . Outcomes were assessed by HgbA1C level at evaluation (eval) , at transplant (pre) , between 3-5 months posttransplant (post) and the most recent (MR) (avg 62 months SD 75.4 months) . Results: 133 patients underwent pancreas transplant during the study period, 85 SPK (62%) 39 PAK (30%) and PTA (8%) . (14%) patients suffered graft loss in the first year and were excluded from analysis. Overall, 1, and 5-year pancreas graft survival was 86% and 82%. 96 (84%) had type 1 diabetes (T1D) and 18 (16%) had type 2 diabetes (T2D) . Of the 114 patients, 33 (29%) utilized CGM with or without pump (CGM) prior to transplant and had a lower Hgb A1C (%) than those without (nonCGM) (8.18 SD 1.5 vs. 8.75 SD 1.9 p=0.04) . Hgb A1C then improved for the nonCGM group during their time on the waitlist (8.75 to 8.36 SD 1.8 p=0.004) but not the CGM group (8.18 to 8.SD 1.3 p=0.24) . Post-transplant saw significant improvement in CGM pre 8.to post 5.0 (SD.6 p=2.7E-17) and MR 5.3 (SD 0.7 p=9.9E-14) and in nonCGM pre 8.4 to post 5.2 (SD 0.62 p= 2.9E-29) and MR 5.4 (SD 0.7 p= 7.3E-29) . Conclusion: Considering the clinical challenges of staying in range for difficult to treat diabetes, leading to HgbA1C goal of ≥7%, solid organ pancreas transplantation offers superior glycemic control compared to advanced insulin delivery systems with CGM. Disclosure K.R.Mccune: None. G.Dube: None. L.E.Ratner: Advisory Panel; CareDx, Immunocore, Ltd., Natera, Stock/Shareholder; Gilead Sciences, Inc., Hansa BioPharma.

Left lateral segment pediatric liver transplantation: a 25 year experience at Mount Sinai.

Outcomes of left lateral segment (LLS) grafts in pediatric recipients were compared between living (LD-LLS) and deceased donor (DD-LLS) grafts. 195 LLS grafts (99DD-LLS-96LD-LLS) were analyzed with a median follow-up of 9.1years. The primary endpoints were overall patient/graft survival. LD-LLS grafts were younger (0.9vs.1.4years, p=0.039), more likely to have a fulminant liver failure (17.9%vs.5.3%,p=0.002), less likely to have a metabolic disorder (6.3%vs.25.5%,p=0.002), and less likely to be undergoing retransplantation (5.3% vs.16.2%,p=0.015). There was a trend toward decreased hepatic artery thrombosis in LD-LLS grafts (6.6% vs. 15.5%,p=0.054). No differences in the overall biliary complications occurred. The LD-LLS group had prolonged survival compared to the DD-LLS group with 10-year survival rates of 81%, and 74% (p=0.005), respectively. LD-LLS grafts had longer graft survival compared to DD-LLS grafts (10-year graft survival 85%vs.67%,p=0.005). Recipient age >1year (HR 2.39,p=0.026), aortic reconstruction (HR 2.12,p=0.046) and vascular complication (HR 3.12,p<0.001) were independent predictors of poor patient survival. Non-biliary liver disease (HR 2.17,p=0.015), DD-LLS (HR 2.06,p=0.034) and vascular complication (HR 4.61,p<0.001) were independent predictors of poor graft survival. The use of SLT remains a viable option with excellent long-term outcomes. We show improved graft and patient survival with living donor grafts.

The Impact of Obesity and Associated Comorbidities on the Outcomes after Renal Transplantation with a Living Donor vs. Deceased Donor Grafts.

Background: Obesity among kidney transplant (KT) recipients can lead to metabolic comorbidity-associated deaths. This study compares post-KT survival between obese and non-obese patients and outcomes of living donor (LD) and deceased donor (DD) grafts. Methods: Between January 2005–May 2019, 1403 KT recipients from a single center were included in the study, as well as 314 patients (22.4%) with obesity (BMI > 30 kg/m2), 137 DD transplants, and 177 LD transplants. Of the 1089 (77.6%) in the control group (BMI ≤ 30 kg/m2), 384 were DD transplants and 705 LD transplants. The Kaplan–Meier method was used for survival analysis and a Cox regression was used to identify risk factors for graft loss and mortality. Propensity score matching analysis adjusting for age, IHD, and T2DM was performed. Results: The study group had higher incidence of obesity related comorbidities, delayed graft function and primary non function (p < 0.001). One-, 5-and 10-year patient and graft survival were lower in the study group (p < 0.001). Subgroup analysis of graft survival according to type of graft shows a difference in the DD (p = 0.002) but not in the LD group (p = 0.220). However, mortality was higher in both groups (LD, p = 0.045; DD, p = 0.004). Risk factors for mortality were age, T2DM, IHD, and DD, and for graft failure: IHD, BMI, donor age, re-transplant, and DD. Propensity score analysis shows an odds ratio of 0.81 for graft failure and 0.93 for death in the study group (95% CI = 0.55, 1.21, p = 0.3 and CI = 0.59, 1.46, p = 0.7, respectively). Conclusions: Recipient age and metabolic comorbidities should be emphasized when evaluating patients with obesity. We suggest considering weight loss interventions using the new GLP-1 inhibitors and bariatric procedures in selected patients to prepare overweight patients for transplant.

Hospital-Based Health Technology Assessment of Machine Perfusion Systems for Human Liver Transplantation

Based on published data, we have carried out a hospital-based health technology assessment of machine perfusion in adult liver transplantation using cold storage as a comparator, and within the perspective of a national health system-based hospital practice and disease-related group reimbursement policy. A systematic literature review on machine perfusion for adult liver transplantation was conducted exploring the Pubmed, CINAHL, Scopus, Embase, and Cochrane databases. The literature was analyzed with the intent to provide information on 6 dimensions and 19 items of the hospital-based health technology assessment framework derived from previous studies. Out of 705 references, 47 (6.7%) were retained for current analysis. Use of machine perfusion was associated with advantages over cold storage, i.e., a 10%–50% reduced risk for early allograft dysfunction, 7%–15% less ischemia reperfusion injury; 7%–50% fewer ischemic biliary complications, comparable or improved 1-year graft and patient survival, and up to a 50% lower graft discard rate. Hospital stay was not longer, and technical failures were anecdotal. Information on costs of machine perfusion is limited, but this technology is projected to increase hospital costs while cost-effectiveness analysis requires data over the transplant patient lifetime. No hospital-based health technology assessment study on machine perfusion in liver transplantation was previously conducted. From the hospital perspective, there is evidence of the clinical advantages of this novel technology, but strategies to counterbalance the increased costs of liver transplantation are urgently needed. Further studies should focus on the ethical, social, and organizational issues related to machine perfusion.

Primary Liver Transplantation vs. Transplant after Kasai Portoenterostomy for Infants with Biliary Atresia.

Introduction: Primary liver transplants (pLT) in patients with biliary atresia (BA) are infrequent, since most babies with BA undergo a prior Kasai portoenterostomy (KPE). This study compared transplant outcomes in children with BA with or without a prior KPE. We hypothesized that pLT have less morbidity and better outcomes compared to those done after a failed KPE. Methods: A retrospective review of patients with BA transplanted at our institution was performed. Patients were included if they received a pLT or if they were transplanted less than 2 years from KPE. Outcomes were compared between those groups. Comparisons were also made based on era (early: 1997–2008 vs. modern: 2009–2020). p < 0.05 was considered significant. Results: Patients who received a pLT were older at diagnosis (141.5 ± 46.0 vs. KPE 67.1 ± 25.5 days, p < 0.001). The time between diagnosis and listing for transplant was shorter in the pLT group (44.5 ± 44.7 vs. KPE 140.8 ± 102.8 days, p < 0.001). In the modern era, the calculated PELD score for the pLT was significantly higher (23 ± 8 vs. KPE 16 ± 8, p = 0.022). Two waitlist deaths occurred in the KPE group (none in pLT, p = 0.14). Both the duration of transplant surgery and transfusion requirements were similar in both groups. There was a significant improvement in graft survival in transplants after KPE between eras (early era 84.3% vs. modern era 97.8%, p = 0.025). The 1-year patient and graft survival after pLT was 100%. Conclusions: Patient and graft survival after pLT are comparable to transplants after a failed KPE but pLT avoids a prior intervention. There was no significant difference in pre- or peri-transplant morbidity between groups other than wait list mortality. A multicenter collaboration with more patients may help demonstrate the potential benefits of pLT in patients predicted to have early failure of KPE.

Distinct Phenotypes of Kidney Transplant Recipients in the United States with Limited Functional Status as Identified through Machine Learning Consensus Clustering.

Background: There have been concerns regarding increased perioperative mortality, length of hospital stay, and rates of graft loss in kidney transplant recipients with functional limitations. The application of machine learning consensus clustering approach may provide a novel understanding of unique phenotypes of functionally limited kidney transplant recipients with distinct outcomes in order to identify strategies to improve outcomes. Methods: Consensus cluster analysis was performed based on recipient-, donor-, and transplant-related characteristics in 3205 functionally limited kidney transplant recipients (Karnofsky Performance Scale (KPS) < 40% at transplant) in the OPTN/UNOS database from 2010 to 2019. Each cluster’s key characteristics were identified using the standardized mean difference. Posttransplant outcomes, including death-censored graft failure, patient death, and acute allograft rejection were compared among the clusters Results: Consensus cluster analysis identified two distinct clusters that best represented the clinical characteristics of kidney transplant recipients with limited functional status prior to transplant. Cluster 1 patients were older in age and were more likely to receive deceased donor kidney transplant with a higher number of HLA mismatches. In contrast, cluster 2 patients were younger, had shorter dialysis duration, were more likely to be retransplants, and were more likely to receive living donor kidney transplants from HLA mismatched donors. As such, cluster 2 recipients had a higher PRA, less cold ischemia time, and lower proportion of machine-perfused kidneys. Despite having a low KPS, 5-year patient survival was 79.1 and 83.9% for clusters 1 and 2; 5-year death-censored graft survival was 86.9 and 91.9%. Cluster 1 had lower death-censored graft survival and patient survival but higher acute rejection, compared to cluster 2. Conclusion: Our study used an unsupervised machine learning approach to characterize kidney transplant recipients with limited functional status into two clinically distinct clusters with differing posttransplant outcomes.

Good post-transplant outcomes using liver donors after circulatory death when applying strict selection criteria: a propensity-score matched-cohort study

Introduction and ObjectivesOutcomes of liver transplantation (LT) with donors after circulatory death (DCD) have been considered suboptimal due to higher rates of ischemic cholangiopathy, especially when the super-rapid recovery (SRR) technique is used. This study aimed to compare the incidence of complications between recipients receiving DCD vs those receiving donors after brain death (DBD) in a large-volume liver transplant centre. MethodsWe performed a retrospective cohort study (LT from January 2015 to December 2018) comparing recipients who underwent a LT with DCD vs. a control group of LT with DBD, matched 1:1 without replacement by propensity score matching that included the following variables: LT indication, recipient sex and age, donor age and MELD score. Results51 recipients with DCD-LT (29 SRR, 22 normothermic regional perfusion [NRP]) were matched with 51 DBD-LT recipients. Biliary complications were more frequent in DCD, 10% (n=5), all with SRR technique, vs 2% (n=1) in the DBD group, p=0.2. Two patients (4%) suffered primary graft non-function in the DCD group (1 SRR and 1 NRP) versus zero in the DBD group (p=0.49). Postoperative bleeding and reinterventions were also higher in the DCD group: 7 (13.7%) vs 1 (1.95%) and 8 (15.7%) vs 2 (3.9%) respectively (p=0.06 and 0.09). On the 1st postoperative day AST/ALT peak was higher in DCD (p≤0001). The incidence of rejection, vascular complications, renal injury, hospital stay, and readmissions were similar in both groups. Cumulative 1-, 2-, 3- and 4-year graft and patient survival were also similar. ConclusionsDCD donors are an adequate option to increase the donor pool in LT, achieving similar graft and patient survival rates to those achieved with DBD donors, especially when the NRP technique is used.

Outcomes and Allograft Survival of Patients Who Underwent a Second Kidney Transplant and Were Followed Up for 10 Years

Kidney transplantation is the treatment of choice for end-stage kidney disease, and a second transplantation becomes an opportunity for a better chance for long-term survival and quality of life. This study aimed to evaluate the outcomes and graft survival of patients transplanted a second time in comparison with single kidney transplant patients. This retrospective observational study was conducted using a cohort of kidney transplant patients from 2008 to 2018. Fifty patients who underwent first transplant were randomly selected as group 1 (G1), and 31 patients who received a second kidney transplant as group 2 (G2). Outcomes, graft, and patient survival were assessed. G2 patients had higher proportions of rejection episodes and graft loss than G1. Fifteen (48.39%) patients from G2 maintained functioning grafts during follow-up, while 16 (51.61%) lost their grafts. The 10-year graft survival rate for patients with first transplant was 76.66%; it was 46.09% for retransplanted patients (P=0.005). There was no statistically significant difference in patient survival between G1 and G2. Allograft survival rates of the first and second transplant with living donors had no statistically significant difference, but for deceased donors, poor graft survival was observed for the second allograft.

Graphical comparison of surgeon outcomes for the audit of a national corneal transplant registry (OTAG study 32).

To compare Kaplan-Meier survival curves and funnel plots for the audit of surgeon-specific corneal transplantation outcomes. We obtained data on all patients with Fuchs endothelial dystrophy (FED) receiving a first corneal transplant in one eye between January 2012 and December 2017. We produced 2-year Kaplan-Meier graft survival curves to compare a simulated individual surgeon's graft survival rate to national pooled data. We used funnel plots to compare all surgeon outcomes to the national graft survival rate with superimposed 95 and 99.8% confidence limits. We defined an outlier as a surgeon who performed ≥10 transplants and had graft survival below the 99.8% national lower limit. To assess the effect of the surgeon case mix, we also compared unadjusted and risk-adjusted graft survival rates. There were 3616 first corneal transplants for FED patients with complete data, performed or overseen by 196 surgeons. The 2-year national graft survival rate was 88%. The median change from the unadjusted to the risk-adjusted graft survival rate for individual surgeons was 0% (IQR: 0%--2%). Of the 108 surgeons who had performed ≥10 transplants, we identified two outliers based on the unadjusted graft survival funnel plot, compared to four outliers based on the risk-adjusted graft survival funnel plot. Funnel plots provide a visually accessible method for comparing individual graft survival rates to the national rate. Risk-adjustment accounts for clinical factors, and this has advantages for audit and clinical governance.

Kidney donor profile index and post-transplant health care utilization: Implications for value of transplant care delivery.

Centers discard high kidney donor profile index (KDPI) allografts, potentially related to delayed graft function and prolonged hospital use by kidney transplant recipients (KTR). We sought to determine whether high KDPI KTRs have excess health care utilization. We conducted a retrospective cohort study from a high-volume center analyzing KTRs from January 3, 2011 to April 12, 2015 (n=652). We measured differences in hospital use, emergency visits, and outpatient visits within the first 90 days between low (≤85%) versus high KDPI (>85%) KTRs, as well as long-term graft function and patient survival. High (n=107) and low KDPI (n=545) KTRs had similar length of stay (median = 3 days, P=.66), and readmission rates at 7, 30, and 90 days after surgery (all, P>.05). High KDPI kidneys were not associated with excess utilization of the hospital, emergency services, outpatient transplant clinics, or ambulatory infusion visits on univariate or multivariate analysis (all, P>.05). Low KDPI KTRs had significantly better eGFR at 2years (Low vs. High KDPI: 60.35 vs. 41.54 ml/min, P<.001), but similar 3-year patient and graft survival (both, P>.09). High and low KDPI KTRs demonstrated similar 90-day risk-adjusted health care utilization, which should encourage use of high KDPI kidneys.