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INTRODUCTION: Various studies have demonstrated that low-Model for End-Stage Liver Disease (MELD) living-donor liver transplant (LDLT) recipients have better outcomes with improved patient survival than deceased-donor liver transplantation (DDLT) recipients. LDLT recipients gain the most from being transplanted at MELD <25-30; however, some existing data have outlined that LDLT may provide equivalent outcomes in high-MELD and low-MELD patients, although the term "high" MELD is arbitrarily defined in the literature and various cut-off scores are outlined between 20 and 30, although most commonly, the dividing threshold is 25. The aim of this meta-analysis was to compare LDLT in high-MELD with that in low-MELD recipients to determine patient survival and graft survival, as well as perioperative and postoperative complications. METHODS: Following PROSPERO registration CRD-42021261501, a systematic database search was conducted for the published literature between 1990 and 2021 and yielded a total of 10 studies with 2183 LT recipients; 490 were HM-LDLT recipients and 1693 were LM-LDLT recipients. RESULTS: Both groups had comparable mortality at 1, 3 and 5 years post-transplant (5-year HR 1.19; 95% CI 0.79-1.79; p-value 0.40) and graft survival (HR 1.08; 95% CI 0.72, 1.63; p-value 0.71). No differences were observed in the rates of major morbidity, hepatic artery thrombosis, biliary complications, intra-abdominal bleeding, wound infection and rejection; however, the HM-LDLT group had higher risk for pulmonary infection, abdominal fluid collection and prolonged ICU stay. CONCLUSIONS: The high-MELD LDLT group had similar patient and graft survival and morbidities to the low-MELD LDLT group, despite being at higher risk for pulmonary infection, abdominal fluid collection and prolonged ICU stay. The data, primarily sourced from high-volume Asian centers, underscore the feasibility of living donations for liver allografts in high-MELD patients. Given the rising demand for liver allografts, it is sensible to incorporate these insights into U.S. transplant practices.

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Background: Direct-acting antivirals for the treatment of hepatitis C virus (HCV) have improved outcomes in liver transplant recipients (LTRs). However, the timing of HCV treatment and approach to treating rejection have not been well described. Additionally, pharmacists' roles in these comprehensive areas have not been investigated. Methods: This single-center, retrospective, cohort review compared 1-year graft and patient survival between HCV-positive and HCV-negative LTRs. Secondary endpoints included 1-year rejection rates, HCV sustained virologic response and time to HCV treatment. Results: Ninety-two HCV Nucleic Acid Amplification Test (NAT)-positive LTRs were matched 1:1 to HCV-seronegative LTRs. One-year graft and patient survival were similar between groups. HCV-positive LTRs were more likely to experience biopsy-proven acute rejection (BPAR), and despite treatment with pulse steroids, there was no impact on graft survival or occurrence of fibrosing cholestatic hepatitis (FCH). Time to HCV treatment was 5.4-6.4 months post-transplant, with no treatment failures or impact on graft or patient survival. Conclusions: No difference was seen in graft survival at 1 year between HCV-positive and HCV-seronegative LTRs. Delayed time to treatment of HCV and treatment of rejections in the HCV-positive cohort did not impact outcomes. However, pharmacist-driven protocols could ensure more efficient initiation of HCV treatment in the future.

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INTRODUCTION: Platelet sequestration, inflammation, and inappropriate coagulation cascade activation are prominent in liver xenotransplant models and are associated with poor outcomes. Here, we evaluate a cassette of six additional genetic modifications to reduce anti-pig antibody binding (α-1,3-galactosyl transferase knockout [GalTKO]) and target coagulation dysregulation (human endothelial protein C receptor [hEPRC] and thrombomodulin [hTBM]), complement pathway regulation (human membrane cofactor protein, hCD46), inflammation heme oxygenase 1 [hHO-1]), and a self-recognition receptor (integrin-associated protein [hCD47]), as well as donor pharmacologic treatments designed to blunt these phenomena. METHODS: Livers from GaltKO.hCD46 pigs ("2-gene," n = 3) and GalTKO.hCD46 pigs also transgenic for hEPRC, hTBM, hCD47, and hHO-1 ("6-gene," n = 4) were perfused ex vivo with whole human blood. Six-gene pigs were additionally pretreated with desmopressin (DDAVP) and clodronate liposomes to deplete vWF and kupffer cells, respectively. RESULTS: The average perfusion times increased from 304 (±148) min in the 2-gene group to 856 (±61) min in the 6-gene group (p = .010). The average heparin administration was decreased from 8837 U/h in the 2-gene to 1354 U/h in the 6-gene group (p = .047). Platelet sequestration tended to be delayed in the 6-gene group (p = .070), while thromboxane B2 (TXB2, a platelet activation marker) levels were lower over the first hour (p = .044) (401 ± 124 vs. 2048 ± 712 at 60 min). Thrombin production as measured by F1+2 levels tended to be lower in the 6-gene group (p = .058). CONCLUSIONS: The combination of the hEPCR.hTBM.hCD47.hHO-1 cassette along with donor pig DDAVP and clodronate liposome pretreatment was associated with prolonged function of xenoperfused livers, reduced coagulation pathway perturbations, and decreased TXB2 elaboration, and reflects significant progress to modulate liver xenograft injury in a pig to human model.

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BACKGROUND: Outcomes of liver transplantation (LT) from donation after circulatory death (DCD) have been improving; however, ischemic cholangiopathy (IC) continues to be a problem. In 2014, measures to minimize donor hepatectomy time (DHT) and cold ischemic time (CIT) have been adopted to improve DCD LT outcomes. METHODS: Retrospective review of all patients who underwent DCD LT between 2005 and 2017 was performed. We compared outcomes of patients who were transplanted before 2014 (historic group) with those who were transplanted between 2014 and 2017 (modern group). RESULTS: We identified 112 patients; 44 were in the historic group and 68 in the modern group. Donors in the historic group were younger (26.5 versus 33, P = 0.007) and had a lower body mass index (26.2 versus 28.2, P = 0.007). DHT (min) and CIT (h) were significantly longer in the historic group (21.5 versus 14, P < 0.001 and 5.3 versus 4.2, P < 0.001, respectively). Fourteen patients (12.5%) developed IC, with a significantly higher incidence in the historic group (23.3% versus 6.1%, P = 0.02). There was no difference in graft and patient survival between both groups. CONCLUSION: In appropriately selected recipients, minimization of DHT and CIT may decrease the incidence of IC. These changes can potentially expand the DCD donor pool.

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Acute on chronic liver failure (ACLF) carries a poor prognosis unless liver transplantation is offered. We present risk factors associated with proceeding with liver transplantation in patients with ACLF. METHODS: A retrospective review of all patients with ACLF who presented to a single transplant center between January 2016 and December 2017 was performed. We compared patients who were transplanted with patients who were not. RESULTS: During the study period, 144 patients with ACLF were identified, 86 patients (59.7%) were transplanted, and 58 were not. The transplanted patients had a lower number of failed organs (4 versus 5, P < 0.001) and lower incidence of ACLF grade 3 (76.7% versus 94.8%, P = 0.014) compared with nontransplanted patients. Liver transplantation offered a 1-y survival of 86% as compared to 12% in the nontransplanted group. Hospital charges were significantly higher among transplanted patients as compared with the nontransplanted patients ($227 886 versus $88 900, P < 0.001). Elevated serum lactate was a risk factor in not offering liver transplantation in ACLF patients. CONCLUSIONS: In appropriately selected patients with ACLF, liver transplantation is feasible and can provide above 86% 1-y patient survival even in grade 3 ACLF.

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The transplantation of organs across species offers the potential to solve the shortage of human organs. While activation of human platelets by human von Willebrand factor (vWF) requires vWF activation by shear stress, contact between human platelets and porcine vWF (pvWF) leads to spontaneous platelet adhesion and activation. This non-physiologic interaction may contribute to the thrombocytopenia and coagulation pathway dysregulation often associated with xenotransplantation of pig organs in nonhuman primates. Pigs genetically modified to decrease antibody and complement-dependent rejection (GTKO.hCD46) were engineered to express humanized pvWF (h*pvWF) by replacing a pvWF gene region that encodes the glycoprotein Ib-binding site with human cDNA orthologs. This modification corrected for non-physiologic human platelet aggregation on exposure to pig plasma, while preserving in vitro platelet activation by collagen. Organs from pigs with h*pvWF demonstrated reduced platelet sequestration during lung (p ≤ .01) and liver (p ≤ .038 within 4 h) perfusion ex vivo with human blood and after pig-to-baboon lung transplantation (p ≤ .007). Residual platelet sequestration and activation were not prevented by the blockade of canonical platelet adhesion pathways. The h*pvWF modification prevents physiologically inappropriate activation of human or baboon platelets by porcine vWF, addressing one cause of the thrombocytopenia and platelet activation observed with xenotransplantation.

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Herein, we performed a meta-analysis of published clinical outcomes of corona virus disease 2019 (COVID-19) in hospitalized kidney transplant recipients. A systematic database search was conducted between December 1, 2019 and April 20, 2020. We analyzed 48 studies comprising 3137 kidney transplant recipients with COVID-19. Fever (77%), cough (65%), dyspnea (48%), and gastrointestinal symptoms (28%) were predominant on hospital admission. The most common comorbidities were hypertension (83%), diabetes mellitus (34%), and cardiac disease (23%). The pooled prevalence of acute respiratory distress syndrome and acute kidney injury were 58% and 48%, respectively. Invasive ventilation and dialysis were required in 24% and 22% patients, respectively. In-hospital mortality rate was as high as 21%, and increased to over 50% for patients in intensive care unit (ICU) or requiring invasive ventilation. Risk of mortality in patients with acute respiratory distress syndrome (ARDS), on mechanical ventilation, and ICU admission was increased: OR = 19.59, OR = 3.80, and OR = 13.39, respectively. Mortality risk in the elderly was OR = 3.90; however, no such association was observed in terms of time since transplantation and gender. Fever, cough, dyspnea, and gastrointestinal symptoms were common on admission for COVID-19 in kidney transplant patients. Mortality was as high as 20% and increased to over 50% in patients in ICU and required invasive ventilation.

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Increased worldwide focus on maximal donor utilization and transplantation of patients once considered too ill to survive liver transplantation may increase the otherwise rare frequency of catastrophic graft failure. Although the deleterious effects of an acutely failing allograft have been established for decades, the optimal strategy in this patient population in the perioperative period remains ill-defined. METHODS: A retrospective review of all liver transplant recipients with perioperative failure leading to transplant hepatectomy between January 1, 2014 and June 30, 2017 was performed. All patients were supported with MARS therapy while awaiting retransplantation. RESULTS: Four patients experienced catastrophic graft failure from massive exsanguination and liver fracture (1), portal vein and hepatic artery thrombosis (1), idiopathic necrosis (1), and necrosis from inadequate donor flushing/primary nonfunction (1). All patients improved following transplant hepatectomy with portacaval shunting. Patients were supported with intubation, vasopressors, renal replacement therapy, and Molecular Adsorbent Recirculating System therapy. All patients underwent retransplantation after a mean anhepatic phase of 48.8 (± 5.13) h. Survival to discharge was 75%. CONCLUSIONS: Although catastrophic liver failure is highly challenging, acceptable outcomes can be achieved with timely hepatectomy with portacaval shunt and retransplantation, particularly in patients supported with the Molecular Adsorbent Recirculating System device.

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We present a very rare Case of a 53-year-old female with autosomal dominant polycystic kidney disease (ADPKD) who was incidentally found to have a reno-appendiceal fistula while undergoing open bilateral nephrectomy. The mid-portion of the appendix was fistulized to a cyst in the lower pole of the right kidney. The etiology was likely due to chronic inflammation. An appendectomy was performed along with the planned right nephrectomy to ensure complete removal of the fistulous tract.

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Endothelial dysfunction is common in septic shock and has been shown to impair angiotensin converting enzyme and the renin-angiotensin-aldosterone system (RAAS). Dysregulation of this pathway, which can be measured with plasma renin activity (PRA), is important not only because RAAS dysfunction is associated with increased mortality but also because treatment with angiotensin II (Ang-2) has been shown to decrease mortality. In this case series of 2 patients, serial PRA levels identified septic shock patients with RAAS dysfunction. The patients were treated with Ang-2, an angiotensin type 1 receptor agonist, which resulted in significant improvements in hemodynamics and PRA levels during treatment.

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BACKGROUND: Multiple listing (ML) at >1 transplant center is one mechanism to combat the geographic disparities in liver transplantation (LT) rates. The objective of our study was to determine the impact of multiple listing on LT rates. METHODS: We examined the United Network of Organ Sharing database from 2002 to 2016 after excluding those listed for multiple organs, hepatocellular carcinoma, or living donor LT. The waitlist mortality and LT rates for the ML groups and the single listed (SL) group were compared after stratifying patients by the Model for End-Stage Liver Disease (MELD) with a cutoff at 15 (<15 and ≥15). RESULTS: Of the 83 935 listed during the study period, 80 351 were listed in a single center (SL group), and 3584 were listed in >1 center (ML group). Of the ML groups, 2028 (2.4%) were listed at multiple donor service areas but within the same region (ML-SR) and 1556 (1.9%) listed in different regions (ML-DR). The median MELD at LT was 20, 21, and 24 for ML-DR, ML-SR, and SL groups, respectively (P = 0.001). Although the probability of receiving LT was significantly higher for the ML groups relative to the SL group for both MELD groups (<15 and ≥15), the impact was the highest for ML-DR group. At MELD score <15, the probability of LT was 72% for ML-DR, 38% for ML-SR, and 32% for SL groups. At MELD score ≥15, the probability of LT was 79% for ML-DR, 67% for ML-SR, and 61% for SL groups. CONCLUSIONS: Multiple listing appeared to considerably improve a patient's chance of receiving LT and survival with the highest benefit for those with low MELD scores (<15) listed at multiple regions.

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BACKGROUND: It has been suggested that hospitalized patients may get suboptimal care in nights or on weekends or summer holidays due to sleep deprivation, physician fatigue, or reduced medical staffing. Our objective was to determine whether there were differences in outcomes when surgery was performed in the night (10 pm-6 am), on weekends (Saturday or Sunday), or during summer months (June-August). METHODS: We used United Network for Organ Sharing (UNOS) data sets of adults transplanted between February 27, 2002, and September 30, 2016. We estimated the start time of liver transplant surgery by utilizing the cross-clamp time and cold ischemia time (cross-clamp time + cold ischemia time - 2 h). The survival outcomes were estimated by Kaplan-Meier survival analysis. Patients with hepatocellular carcinoma (HCC) were analyzed separately. The independent effect of time of transplant on outcomes was analyzed after adjusting for common confounders, including Model for End-stage Liver Diseases scores and transplant center volume. RESULTS: During the study period, 4 434 (9.6%) were done in the night, 12 147 (26.4%) over weekends, and 11 976 (26%) during summer months. The graft and patient survival and complications were not influenced by the time of transplant for both HCC and non-HCC population. Cox regression analysis after adjusting for risk factors, including Model for End-stage Liver Diseases, donor risk index, and liver center volume, confirmed that there were no significant differences in outcomes. CONCLUSIONS: Our study showed that the time of transplant surgery whether done during nights, weekends, or summer months had no effect on graft or patient survival irrespective of center volume, patient, or donor risk factors.

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BACKGROUND: Postoperative severe cardiopulmonary failure carries a high rate of mortality. Extracorporeal membrane oxygenation (ECMO) can be used as a salvage therapy when conventional therapies fail. METHODS: We retrospectively reviewed our experience with ECMO support in the early postoperative period after liver transplant between September 2011 and May 2016. RESULTS: Out of 537 liver transplants performed at our institution, seven patients required ECMO support with a median age of 52 and a median MELD score of 28. Veno-venous ECMO was used in four patients with severe respiratory failure while the rest required veno-arterial ECMO for circulatory failure. The median time from transplant to cannulation was 3 days with a median duration of ECMO support of 7 days. All patients except one were successfully decannulated. The median hospital length of stay was 58 days with an in-hospital mortality of 28.6%. CONCLUSION: Extracorporeal membrane oxygenation can be considered a viable rescue therapy in the setting of severe postoperative cardiopulmonary failure. Extracorporeal membrane oxygenation therapy was successful in saving patients who were otherwise unsalvageable.

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INTRODUCTION: Hepatic artery pseudoaneurysm is a rare and potentially fatal complication of liver transplantation with a reported incidence of 0.3-2.6% and associated mortality approaching 75%. Clinical presentation typically includes sudden hypotension, gastrointestinal bleed or abnormal liver function tests within two months of transplantation. We report a series of four cases of hepatic artery pseudoaneurysm in adult liver transplant recipients with the goal of identifying factors that may aid in early diagnosis, prior to the development of life threatening complications. METHODS: A retrospective chart review at a high volume transplant center revealed 4 cases of hepatic artery pseudoaneurysm among 553 liver transplants (Incidence 0.72%) between March 2013 and March 2017. RESULTS: Two of the four patients died immediately after intervention, one patient survived an additional 151 days prior to death from an unrelated condition and one patient survived at two years follow up. All cases utilized multiple imaging modalities that failed to identify the pseudoaneurysm prior to diagnosis with computed tomography angiography (CTA). Two cases had culture proven preoperative intrabdominal infections, while the remaining two cases manifested a perioperative course highly suspicious for infection (retransplant for hepatic necrosis after hepatic artery thrombosis and infected appearing vessel at reoperation, respectively). Three of the four cases either had a delayed biliary anastomosis or development of a bile leak, leading to contamination of the abdomen with bile. Additionally, three of the four cases demonstrated at least one episode of hypotension with acute anemia at least 5 days prior to diagnosis of the hepatic artery pseudoaneurysm. CONCLUSIONS: Recognition of several clinical features may increase the early identification of hepatic artery pseudoaneurysm in liver transplant recipients. These include culture proven intrabdominal infection or high clinical suspicion for infection, complicated surgical course resulting either in delayed performance of biliary anastomosis or a biliary leak, and an episode of hypotension with acute anemia. In combination, the presence of these characteristics can lead the clinician to investigate with appropriate imaging prior to the onset of life threatening complications requiring emergent intervention. This may lead to increased survival in patients with this life threatening complication.

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BACKGROUND: Alcoholic liver disease (ALD) due to alcohol use disorder (AUD) is the primary cause of liver transplantation (LT) in the United States. Studies have found that LT recipients experience a range of physical and emotional difficulties posttransplantation including return to alcohol use, depression, and anxiety. The aim of this study is to better understand the experiences of LT recipients with ALD because they recovered posttransplant to inform the development of a patient-centered intervention to assist patients during recovery. METHODS: Using qualitative methods, researchers conducted semi-structured interviews with 16 ALD LT recipients. The primary topics of the interview were physical recovery, mental health, substance use including alcohol and tobacco use, and financial experiences. Common patient themes were identified and coded. RESULTS: Within the domain of physical health, patients stressed that undergoing LT was a near-death experience, they were helpless, changes in weight influenced their perception of their illness, and they have ongoing medical problems. In the domain of mental health, patients described cognitive impairments during their initial recovery, difficulty in processing the emotions of having a terminal condition, ongoing depression, anxiety, and irritability. The patients also described their perception of having AUD, the last time they used alcohol and their attitude to AUD treatment posttransplant. Patients also described their reliance on one member of their social support network for practical assistance during their recovery and identified one member of their medical team as being of particular importance in providing emotional as well as medical support during recovery. CONCLUSIONS: The patient's description of their lived experience during the months following transplant informed the development of a patient-centered intervention that colocates behavioral health components with medical treatment that helps broaden their social network while addressing topics that emerged from this study.

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PURPOSE OF REVIEW: This review highlights advances in liver xenotransplantation, focusing on immunologic barriers and mechanisms underlying graft failure and recipient demise, and discussion of recent in-vivo results. RECENT FINDINGS: Pig to primate models of liver xenotransplantation have been plagued by thrombocytopenia, anemia, and coagulopathy. It is now known that platelet sequestration is mediated by liver sinusoidal endothelial cells and Kupffer cells in part by asialoglycoprotein receptor 1-driven mechanisms. Xenoantigens, specifically N-glycolylneuraminic acid, play a role in graft injury as well as red blood cell consumption. Finally incompatibilities between coagulation cascade molecules contribute to lethal coagulopathy, but can be counteracted with genetic modifications and coagulation factor supplementation. Survival has markedly increased with this strategy. SUMMARY: An increased understanding of the cellular mechanisms responsible for failure of in-vivo pig to primate liver xenotransplant models has led to improved outcomes, and this recent success supports initial clinical application.

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BACKGROUND: The concept of a minimally invasive live donor nephrectomy developed over 20 years ago. Surgeons gained expertise with the laparoscopic technique and utilized multiple variations that are now utilized in transplant centers throughout the world. Recent modifications include laparoendoscopic single-site and robotic approaches that have been adopted by an additional smaller set of programs. PURPOSE: Review was performed of the following eight different surgical approaches to a "minimally invasive" live donor nephrectomy: laparoscopic (LDN), hand-assisted laparoscopic (HALDN), retroperitoneoscopic (RLDN), hand-assisted retroperitoneoscopic (HARS), single-port laparoscopic (LESS), robotic-assisted laparoscopic (RALDN), mini open, and natural orifice transluminal endoscopic (NOTES). The techniques are described and summaries of available outcomes and complications are presented. CONCLUSIONS: Traditional surgical techniques of open donor nephrectomy have transitioned to minimally invasive techniques. With adoption of these techniques as the preferred approach, several variations have and continue to evolve. The current minimally invasive donor nephrectomy techniques share low complication rates and excellent outcomes.

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BACKGROUND: Although single-port donor nephrectomy offers improved cosmetic outcomes, technical challenges have limited its application to selected centers. Our center has performed over 400 single-port donor nephrectomies. The da Vinci single-site robotic platform was utilized in an effort to overcome the steric, visualization, ergonomic, and other technical limitations associated with the single-port approach. MATERIALS AND METHODS: Food and Drug Administration device exemption was obtained. Selection criteria for kidney donation included body mass index <35, left kidney donors, and ≤2 renal arteries. After colonic mobilization using standard single-port techniques, the robotic approach was utilized for ureteral complex and hilar dissection. RESULTS: Three cases were performed using the robotic single-site platform. Average total operative time was 262 ±â€¯42 min including 82 ±â€¯16 min of robotic use. Docking time took 20 ±â€¯10 min. Blood loss averaged 77 ±â€¯64 mL. No intraoperative complications occurred, and all procedures were completed with our standard laparoscopic single-port approach. CONCLUSIONS: This is the first clinical experience of robotic-assisted donor nephrectomy utilizing the da Vinci single-site platform. Our experience supported the safety of this approach but found that the technology added cost and complexity without tangible benefit. Development of articulating instruments, energy, and stapling devices will be necessary for increased application of robotic single-site surgery for donor nephrectomy.

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In addition to immune barriers, molecular incompatibilities between species are predicted to limit pig liver survival in primate xenotransplantation models. Assessment and measurement of synthetic function of genetically modified porcine livers after ex vivo perfusion with human blood have not previously been described. Eight porcine livers from α1,3-galactosyl transferase knockout and human membrane cofactor (GalTKO.hCD46), six livers from GalTKO.hCD46 and N-glycolylneuraminic acid knockout (GalTKO.hCD46.Neu5GcKO), and six livers from GalTKO.hCD46 with humanized decay-accelerating factor (hCD55), endothelial protein C receptor (hEPCR), tissue factor pathway inhibitor (hTFPI), and integrin-associated protein (hCD47) (GalTKO.hCD46.hCD55.hEPCR.hTFPI.hCD47) pigs were perfused with human blood under physiologic conditions. Timed blood samples were tested for liver enzymes and for pig-specific albumin production via Western blot. Porcine albumin levels increased with time in all experiments. By densitometry, GalTKO.hCD46.Neu5GcKO livers had the highest albumin levels, measured both as total produced, and when controlled for perfusion duration, compared to GalTKO.hCD46 (P = .068) and GalTKO.hCD46.hCD55.hEPCR.hTFPI.hCD47 livers (P = .04). Porcine livers perfused with human blood demonstrated the synthetic ability to produce albumin in all cases. GalTKO.hCD46.Neu5GcKO pig livers demonstrated the most robust albumin production. This suggests that the Neu5GcKO phenotype provides a protective effect on the graft due to decreased human antibody recognition and graft injury.

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