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991.
Outcomes following hepatitis C virus (HCV)-viremic heart transplantation into HCV-negative recipients with HCV treatment are good. We assessed cost-effectiveness between cohorts of transplant recipients willing and unwilling to receive HCV-viremic hearts. Markov model simulated long-term outcomes among HCV-negative patients on the transplant waitlist. We compared costs (2018 USD) and health outcomes (quality-adjusted life-years, QALYs) between cohorts willing to accept any heart and those willing to accept only HCV-negative hearts. We assumed 4.9% HCV-viremic donor prevalence. Patients receiving HCV-viremic hearts were treated, assuming $39 600/treatment with 95% cure. Incremental cost-effectiveness ratios (ICERs) were compared to a $100 000/QALY gained willingness-to-pay threshold. Sensitivity analyses included stratification by blood type or region and potential negative consequences of receipt of HCV-viremic hearts. Compared to accepting only HCV-negative hearts, accepting any heart gained 0.14 life-years and 0.11 QALYs, while increasing costs by $9418/patient. Accepting any heart was cost effective (ICER $85 602/QALY gained). Results were robust to all transplant regions and blood types, except type AB. Accepting any heart remained cost effective provided posttransplant mortality and costs among those receiving HCV-viremic hearts were not >7% higher compared to HCV-negative hearts. Willingness to accept HCV-viremic hearts for transplantation into HCV-negative recipients is cost effective and improves clinical outcomes.  相似文献   
992.
Organ transplant recipients (OTRs) are at increased risk of cutaneous malignancy. Skin disorders in OTRs of color (OTRoC) have rarely been systematically assessed. We aimed to ascertain the burden of skin disease encountered in OTRoC by prospectively collecting data from OTRs attending 2 posttransplant skin surveillance clinics: 1 in London, UK and 1 in Philadelphia, USA. Retrospective review of all dermatological diagnoses was performed. Data from 1766 OTRs were analyzed: 1024 (58%) white, 376 (21%) black, 261 (15%) Asian, 57 (3%) Middle Eastern/Mediterranean (ME/M), and 48 (2.7%) Hispanic; and 1128 (64%) male. Viral infections affected 45.1% of OTRs, and were more common in white and ME/M patients (P < .001). Fungal infections affected 28.1% and were more common in ME/M patients (P < .001). Inflammatory skin disease affected 24.5%, and was most common in black patients (P < .001). In addition, 26.4% of patients developed skin cancer. There was an increased risk of skin cancer in white vs nonwhite OTRs (HR 4.4, 95% CI 3.5-5.7, P < .001): keratinocyte cancers were more common in white OTRs (P < .001) and Kaposi sarcoma was more common in black OTRs (P < .001). These data support the need for programs that promote targeted dermatology surveillance for all OTRs, regardless of race/ethnicity or country of origin.  相似文献   
993.
Kidney transplant program performance in the United States is commonly measured by posttransplant outcomes. Inclusion of pretransplant measures could provide a more comprehensive assessment of transplant program performance and necessary information for patient decision-making. In this study, we propose a new metric, the waitlisting rate, defined as the ratio of patients who are waitlisted in a center relative to the person-years referred for evaluation to a program. Furthermore, we standardize the waitlisting rate relative to the state average in Georgia, North Carolina, and South Carolina. The new metric was used as a proof-of-concept to assess transplant-program access compared to the existing transplant rate metric. The study cohorts were defined by linking 2017 United States Renal Data System (USRDS) data with transplant-program referral data from the Southeastern United States between January 1, 2012 and December 31, 2016. Waitlisting rate varied across the 9 Southeastern transplant programs, ranging from 10 to 22 events per 100 patient-years, whereas the program-specific waitlisting rate ratio ranged between 0.76 and 1.33. Program-specific waitlisting rate ratio was uncorrelated with the transplant rate ratio (r = −.15, 95% CI, −0.83 to 0.57). Findings warrant collection of national data on early transplant steps, such as referral, for a more comprehensive assessment of transplant program performance and pretransplant access.  相似文献   
994.
The role of ex vivo normothermic perfusion (EVNP) in both organ viability assessment and reconditioning is increasingly being demonstrated. We report the use of this emerging technology to facilitate the transplantation of a pair of donor kidneys with severe acute kidney injury (AKI) secondary to rhabdomyolysis. Donor creatinine was 10.18 mg/dl with protein (30 mg/dl) present in urinalysis. Both kidneys were declined by all other transplantation units and subsequently accepted by our unit. The first kidney was perfused with red cell-based perfusate at 37°C for 75 min, mean renal blood flow was 110 ml/min/100 g and produced 85 ml of urine. Having demonstrated favorable macroscopic appearance and urine output, the kidney was transplanted into a 61-year-old peritoneal dialysis dependent without complication. Given the reassuring information from the first kidney provided by EVNP, the second kidney was not perfused with EVNP and was directly implanted to a 64-year-old patient. The first kidney achieved primary function and the second functioned well after delayed graft function. Recipient eGFR have stabilized at 88.5 and 55.3, respectively (ml/min/1.73 m2), at 2 months posttransplant.  相似文献   
995.
Desensitization has enabled incompatible living donor kidney transplantation (ILDKT) across HLA/ABO barriers, but added immunomodulation might put patients at increased risk of infections. We studied 475 recipients from our center from 2010 to 2015, categorized by desensitization intensity: none/compatible (n = 260), low (0-4 plasmaphereses, n = 47), moderate (5-9, n = 74), and high (≥10, n = 94). The 1-year cumulative incidence of infection was 50.1%, 49.8%, 66.0%, and 73.5% for recipients who received none, low, moderate, and high-intensity desensitization (P < .001). The most common infections were UTI (33.5% of ILDKT vs. 21.5% compatible), opportunistic (21.9% vs. 10.8%), and bloodstream (19.1% vs. 5.4%) (P < .001). In weighted models, a trend toward increased risk was seen in low (wIRR = 0.771.402.56,P = .3) and moderately (wIRR = 0.881.352.06,P = .2) desensitized recipients, with a statistically significant 2.22-fold (wIRR = 1.332.223.72,P = .002) increased risk in highly desensitized recipients. Recipients with ≥4 infections were at higher risk of prolonged hospitalization (wIRR = 2.623.574.88, P < .001) and death-censored graft loss (wHR = 1.154.0113.95,P = .03). Post–KT infections are more common in desensitized ILDKT recipients. A subset of highly desensitized patients is at ultra-high risk for infections. Strategies should be designed to protect patients from the morbidity of recurrent infections, and to extend the survival benefit of ILDKT across the spectrum of recipients.  相似文献   
996.
Ischemia-reperfusion injury (IRI) results in increased rates of delayed graft function and early graft loss. It has recently been reported that hydrogen sulfide (H2S) protects organ grafts against prolonged IRI. Here, we investigated whether the preservation of pancreas in University of Wisconsin (UW) solution supplemented with AP39, which is a mitochondrial-targeted H2S donor, protected pancreatic islets against IRI and improved islet function. Porcine pancreata were preserved in the UW solution with AP39 (UW + AP39) or the vehicle (UW) for 18 h, followed by islet isolation. The islet yields before and after purification were significantly higher in the UW + AP39 group than in the UW group. The islets isolated from the pancreas preserved in UW + AP39 exhibited significantly decreased levels of reactive oxygen species (ROS) production and a significantly increased mitochondrial membrane potential as compared to the islets isolated from the pancreas preserved in the vehicle. We found that the pancreas preserved in UW + AP39 improved the outcome of islet transplantation in streptozotocin-induced diabetic mice. These results suggest that the preservation of pancreas in UW + AP39 protects the islet grafts against IRI and could thus serve as a novel clinical strategy for improving islet transplantation outcomes.  相似文献   
997.
Objectifying donor lung quality is difficult and currently there is no consensus. Several donor scoring systems have been proposed in recent years. They all lack large-scale external validation and widespread acceptance. A retrospective evaluation of 2201 donor lungs offered to the lung transplant program at the Medical University of Vienna between January 2010 and June 2018 was performed. Five different lung donor scores were calculated for each offer (Oto, ET, MALT, UMN-DLQI, and ODSS). Prediction of organ utilization, 1-year graft survival, and long-term outcome were analyzed for each score. 1049 organs were rejected at the initial offer (group I), 209 lungs declined after procurement (group II), and 841 lungs accepted and transplanted (group III). The Oto score was superior in predicting acceptance of the initial offer (AUC: 0.795; CI: 0.776–0.815) and actual donor utilization (AUC: 0.660; CI: 0.618–0.701). Prediction of 1-year graft survival was best using the MALT score, Oto score, and UMN-DLQI. Stratification of early outcome by MALT was significant for length of mechanical ventilation (LMV), PGD3 rates, ICU stay and hospital stay, and in-hospital-mortality, respectively. To the best of our knowledge, this study is the largest validation analysis comparing currently available donor scores. The Oto score was superior in predicting organ utilization, and MALT score and UMN-DLQI for predicting outcome after lung transplantation.  相似文献   
998.
There is a paucity of data on the outcome of liver transplantation (LT) in Budd-Chiari Syndrome (BCS) patients who are listed as status 1. The objective of our study was to determine patient or graft survival following LT in status 1 BCS patients. We utilized United Network for Organ Sharing (UNOS) database to identify all adult patients (> 18 years of age) listed as status 1 with a primary diagnosis of BCS in the United States from 1998 to 2018, and analyzed their outcomes and compared it to non-status 1 BCS patients. Four hundred and forty-six patients with BCS underwent LT between 1998 and 2018, and of these 55 (12.3%) were listed as status 1. There was no difference in long-term post-liver transplant or “intention-to-treat” survival from the time of listing to death or the last day of follow-up between status 1 and non-status 1 groups. Graft and patient survival at 5 years for status 1 patients were 75% and 82%, respectively. Cox regression analysis showed that patients listed as status 1 (aHR: 0.45, p < .02) were associated with a better survival. BCS patients listed as status 1 have excellent survival following emergency LT.  相似文献   
999.
It is unknown if solid organ transplant recipients are at higher risk for severe COVID-19. The management of a lung transplantation (LTx) program and the therapeutic strategies to adapt the immunosuppressive regimen and antiviral measures is a major issue in the COVID-19 era, but little is known about worldwide practice. We sent out to 180 LTx centers worldwide in June 2020 a survey with 63 questions, both regarding the management of a LTx program in the COVID-19 era and the therapeutic strategies to treat COVID-19 LTx recipients. We received a total of 78 responses from 15 countries. Among participants, 81% declared a reduction of the activity and 47% restricted LTx for urgent cases only. Sixteen centers observed deaths on waiting listed patients and eight centers performed LTx for COVID-19 disease. In 62% of the centers, COVID-19 was diagnosed in LTx recipients, most of them not severe cases. The most common immunosuppressive management included a decreased dose or pausing of the cell cycle inhibitors. Remdesivir, hydroxychloroquine, and azithromycin were the most proposed antiviral strategies. Most of the centers have been affected by the COVID-19 pandemic and proposed an active therapeutic strategy to treat LTx recipients with COVID-19.  相似文献   
1000.
Platelet activation and thrombus formation have been implicated to be detrimental for intraportal pancreatic islet transplants. The platelet-specific collagen receptor glycoprotein VI (GPVI) plays a key role in thrombosis through cellular activation and the subsequent release of secondary mediators. In aggregometry and in a microfluidic dynamic assay system modeling flow in the portal vein, pancreatic islets promoted platelet aggregation and triggered thrombus formation, respectively. While platelet GPVI deficiency did not affect the initiation of these events, it was found to destabilize platelet aggregates and thrombi in this process. Interestingly, while no major difference was detected in early thrombus formation after intraportal islet transplantation, genetic GPVI deficiency or acute anti-GPVI treatment led to an inferior graft survival and function in both syngeneic mouse islet transplantation and xenogeneic human islet transplantation models. These results demonstrate that platelet GPVI signaling is indispensable in stable thrombus formation induced by pancreatic islets. GPVI deficiency resulted in thrombus destabilization and inferior islet engraftment indicating that thrombus formation is necessary for a successful intraportal islet transplantation in which platelets are active modulators.  相似文献   
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