Stabilisation of acute-on-chronic liver failure patients before liver transplantation predicts post-transplant survival

Patient Selection for Living Donor Liver Transplantation in Acute-on-chronic Liver Failure

Background and objectives

Acute-on-chronic liver failure (ACLF) is associated with high short-term mortality without liver transplantation (LT). The selection criteria for LT in these patients are not well defined. The objective of this study was to determine factors associated with post-transplant survival in ACLF.

Methods

This was a single-center retrospective study of patients who underwent living donor liver transplantation (LDLT) for ACLF between 2012 and 2022. Out of 1093 transplants, 110 patients had underlying ACLF, based on the European Association for the Study of the Liver-Chronic Liver Failure Consortium (EASL-CLIF) criteria. We looked at factors associated with 1-year posttransplant survival.

Results

The median model for end-stage liver disease (MELD) score was 33.5 (31-38), and the 1-year posttransplant survival was 72%. Six risk factors were associated with posttransplant survival, namely, body mass index > 30 kg/m2 [HR, 4.4; 95% CI, 1.8-10.7], platelet count < 66,000/μl [HR, 2.91; CI,1.2-6.6], poor response to medical treatment [HR, 2.6; CI, 1.1-5.7], drug-resistant bacterial or fungal cultures [HR, 4.2; CI, 1.4-12.4], serum creatinine > 2.5 mg/dl [HR, 3.4; CI, 1.5-7.7], and graft-to-recipient weight ratio < 0.7 [HR, 4.8; CI, 1.4-16.3]. The 1-year post-transplant survival was 84% in patients with 0-2 risk factors (n = 89) and was 6% with 3 risk factors (n = 15) (P < 0.001). For 1-year posttransplant survival, the area under curve (AUC) for the current model was 0.8 (0.69-0.9). The AUC for CLIF-ACLF, Chronic Liver Failure-Sequential Organ Failure Assessment (CLIF-SOFA), and EASL-CLIF ACLF grades was < 0.5.

Conclusion

In LT for ACLF, acceptable survival can be achieved when less than three high-risk factors are present.

Liver transplantation for acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) occurs in the context of advanced liver disease and is associated with hepatic and extrahepatic organ failure, eventually leading to a major risk of short-term mortality. To date, there are very few effective therapeutic options for ACLF. In many cases, liver transplantation is the only life-saving treatment that has acceptable outcomes in carefully selected recipients. This Review addresses key aspects of the use of liver transplantation for patients with ACLF, providing an in-depth discussion of existing evidence regarding candidate selection, the optimal window for transplantation, potential prioritisation of liver grafts for this indication, and the global management of ACLF to bridge patients to liver transplantation.

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Use of machine learning models for the prognostication of liver transplantation: A systematic review

BACKGROUND

Liver transplantation (LT) is a life-saving intervention for patients with end-stage liver disease. However, the equitable allocation of scarce donor organs remains a formidable challenge. Prognostic tools are pivotal in identifying the most suitable transplant candidates. Traditionally, scoring systems like the model for end-stage liver disease have been instrumental in this process. Nevertheless, the landscape of prognostication is undergoing a transformation with the integration of machine learning (ML) and artificial intelligence models.

AIM

To assess the utility of ML models in prognostication for LT, comparing their per formance and reliability to established traditional scoring systems.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we conducted a thorough and standardized literature search using the PubMed/MEDLINE database. Our search imposed no restrictions on publication year, age, or gender. Exclusion criteria encompassed non-English stu dies, review articles, case reports, conference papers, studies with missing data, or those exhibiting evident methodological flaws.

RESULTS

Our search yielded a total of 64 articles, with 23 meeting the inclusion criteria. Among the selected studies, 60.8% originated from the United States and China combined. Only one pediatric study met the criteria. Notably, 91% of the studies were published within the past five years. ML models consistently demonstrated satisfactory to excellent area under the receiver operating characteristic curve values (ranging from 0.6 to 1) across all studies, surpassing the performance of traditional scoring systems. Random forest exhibited superior predictive capa bilities for 90-d mortality following LT, sepsis, and acute kidney injury (AKI). In contrast, gradient boosting excelled in predicting the risk of graft-versus-host disease, pneumonia, and AKI.

CONCLUSION

This study underscores the potential of ML models in guiding decisions related to allograft allocation and LT, marking a significant evolution in the field of prognostication.

Acute decompensation of cirrhosis versus acute-on-chronic liver failure: What are the clinical implications?

It is essential to identify the subgroup of patients who experience poorer outcomes in order to adapt clinical management effectively. In the context of liver disease, the earlier the identification occurs, the greater the range of therapeutic options that can be offered to patients. In the past, patients with acute decompensation (AD) of chronic liver disease were treated as a homogeneous group, with emphasis on identifying those at the highest risk of death. In the last 15 years, a differentiation has emerged between acute-on-chronic liver failure syndrome (ACLF) and AD, primarily due to indications that the latter is linked to a less favorable short-term prognosis. Nevertheless, the definition of ACLF varies among the different knowledge societies, making it challenging to assess its true impact compared with AD. Therefore, the purpose of this review is to provide a detailed analysis emphasizing the critical importance of identifying ACLF in the field of advanced liver disease. We will discuss the differences between Eastern and Western approaches, particularly in relation to the occurrence of liver failure and disease onset. Common characteristics, such as the dynamic nature of the disease course, will be highlighted. Finally, we will focus on two key clinical implications arising from these considerations: the prevention of ACLF before its onset and the clinical management strategies once it develops, including liver transplantation and withdrawal of care.

Liver Transplantation: Contraindication and Ineligibility

Liver transplantation (LT) is a life-saving therapeutic modality for patients with various advanced liver diseases. It is crucial to identify that the patient's illness is sufficiently advanced and unlikely to improve with medical management to justify the need for transplantation. At the same time, it is crucial to identify patients with comorbidities and far advanced disease that would result in an unacceptable outcome after LT. Specific care also is required before deciding on LT in the elderly, acute on chronic liver disease, patients with comorbidities, and hepatocellular carcinoma. Transplantation needs to be timed appropriately to avoid unnecessary LT and ensure that the decision is not left too late to avoid losing the patient without a transplant. Also, important is the decision as to when not to transplant. The current review explores some of these issues of contraindications and ineligibility for LT.

Epidemiology of liver transplantation and post-LT complications in Germany: nationwide study (2005-2018)

BACKGROUND

To date, liver transplantation (LT) is the only curative treatment for cirrhosis and early-diagnosed progressive acute liver failure (ALF). However, LT results in morbidities and mortality even post-LT. Different comorbidities may follow and further increase mortality and morbidity. In this study, we investigated the outcomes and their trends over a period of 14 years among hospitalized patients evaluated for LT, transplant and post-LT in Germany.

METHODS

This German nationwide study investigated the number of admissions of patients hospitalized for evaluation of LT and post-LT on related comorbidities and complications between 2005 and 2018 based on the DRG system with ICD-10/OPS codes. 14 745 patients were put on the LT waiting list and 12 836 underwent LT during the observational period.

RESULTS

The LT number decreased by 2.3% over time, while the waiting list mortality rate increased by 5%. By contrast, the in-hospital mortality rate decreased by 3%, especially in ALF patients (decrease of 16%). Interestingly, admissions of post-LT patients for complications almost doubled, driven mainly by complications of immunosuppression (tripled). Importantly, post-LT patients with acute kidney injury (20.2%) and biliodigestive anastomosis (18.4%) showed the highest in-hospital mortality rate of all complications.

CONCLUSION

In conclusion, the decrease in LT leads most probably to the increased in-hospital mortality of patients on the waiting list. Interestingly, in-hospital mortality decreased in LT patients. Post-LT comorbidities requiring hospitalization increased in the observational period and management of patients post-LT with AKI or biliodigestive anastomosis should be addressed.

Healthcare utilization and outcomes of living donor liver transplantation for patients with APASL-defined acute-on-chronic liver failure

BACKGROUND

Liver transplantation (LT) is associated with excellent survival in patients with acute-on-chronic liver failure (ACLF). There is a lack of data assessing the healthcare utilization and outcomes of patients with APASL-defined ACLF undergoing living donor liver transplantation (LDLT). Our aim was to assess pre-LT healthcare utilization and post-LT outcomes in such patients.

METHODS

Patients with ACLF who underwent LDLT at our center between 1st April 2019 and 1st October 2021 were included.

RESULTS

Seventy-three ACLF patients willing to undergo LDLT were listed; eighteen patients died within 30 days. Fifty-five patients underwent LDLT (age:38.05 ± 14.76 years; alcohol:52.7%; males:81.8%). Most were in grade II ACLF (87.3%) at the time of LDLT (APASL ACLF Research Consortium [AARC] score: 9.05 ± 1; MELD NA: 28.15 ± 4.13). Survival rate was 72.73%; mean follow-up period of 925.21 days; 58.2% (32/55) developed complications during the first year post-LT; 45% (25/55) and 12.7% (7/55) developed infections within and after 3 months. Pre-LT, each patient required a median of 2 (1-4) admissions for 17 (4-45) days. Fifty-six percent (31/55) of patients underwent plasma exchange pre-LDLT. A median amount of Rs. 8,25,090 (INR 26,000-43,58,154) was spent to stabilize the patient (who were sicker and waited longer to undergo LDLT); though post-LT survival benefit was not observed.

CONCLUSIONS

LDLT was associated with 73% survival and, thus, is a viable option in those with APASL-defined ACLF. There was a pre-LT high healthcare resource utilization of plasma exchange, with the intention of optimization, while survival benefit has not been demonstrated.

Review article: Emerging and current management of acute-on-chronic liver failure

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a clinically and pathophysiologically distinct condition from acutely decompensated cirrhosis and is characterised by systemic inflammation, extrahepatic organ failure, and high short-term mortality.

AIMS

To provide a narrative review of the diagnostic criteria, prognosis, epidemiology, and general management principles of ACLF. Four specific interventions that are explored in detail are intravenous albumin, extracorporeal liver assist devices, granulocyte-colony stimulating factor, and liver transplantation.

METHODS

We searched PubMed and Cochrane databases for articles published up to July 2023.

RESULTS

Approximately 35% of hospital inpatients with decompensated cirrhosis have ACLF. There is significant heterogeneity in the criteria used to diagnose ACLF; different definitions identify different phenotypes with varying mortality. Criteria established by the European Association for the Study of the Liver were developed in prospective patient cohorts and are, to-date, the most well validated internationally. Systemic haemodynamic instability, renal dysfunction, coagulopathy, neurological dysfunction, and respiratory failure are key considerations when managing ACLF in the intensive care unit. Apart from liver transplantation, there are no accepted evidence-based treatments for ACLF, but several different approaches are under investigation.

CONCLUSION

The recognition of ACLF as a distinct entity from acutely decompensated cirrhosis has allowed for better patient stratification in clinical settings, facilitating earlier engagement with the intensive care unit and liver transplantation teams. Research priorities over the next decade should focus on exploring novel treatment strategies with a particular focus on which, when, and how patients with ACLF should be treated.

Liver Transplantation in Acute-on-Chronic Liver Failure

In recent years there has been a significant increase in the incidence of acute-on-chronic liver failure (ACLF). This syndrome is characterized by infections, organ failures, and high short-term mortality. Although progress in the management of these sick patients has been evident, liver transplantation (LT) remains the best treatment modality to date. Several studies have reported LT as a feasible option, despite organ failures. The outcomes following LT are inversely related to the grade of ACLF. This review discusses the current literature on the feasibility, futility, timing, and outcomes of LT in patients with ACLF.

Liver Transplantation 2023: Status Report, Current and Future Challenges

Liver transplantation offers live-saving therapy for patients with complications of cirrhosis and stage T2 hepatocellular carcinoma. The demand for organs far outstrips the supply, and innovations aimed at increasing the number of usable deceased donors as well as alternative donor sources are a major focus. The etiologies of cirrhosis are shifting over time, with more need for transplantation among patients with alcohol-associated liver disease and nonalcoholic/metabolic fatty liver disease and less for viral hepatitis, although hepatitis B remains an important indication for transplant in countries with high endemicity. The rise in transplantation for alcohol-associated liver disease and nonalcoholic/metabolic fatty liver disease has brought attention to how patients are selected for transplantation and the strategies needed to prevent recurrent disease. In this review, we present a status report on the most pressing topics in liver transplantation and future challenges.

Should patients with acute-on-chronic liver failure grade 3 receive higher priority for liver transplantation?

In this debate, the authors consider whether patients with acute-on-chronic liver failure grade 3 (ACLF-3) should receive higher liver transplant priority, with reference to the following clinical case: a 62-year-old male with a history of decompensated alcohol-associated cirrhosis, with recurrent ascites and hepatic encephalopathy, and metabolic comorbidities (type 2 diabetes mellitus, arterial hypertension and a BMI of 31 kg/m²). A few days following evaluation for liver transplantation (LT), the patient was admitted to the intensive care unit and placed on mechanical ventilation for neurological failure, FiO₂ of 0.3 with a SpO₂ of 98%, and started on norepinephrine at 0.62 μg/kg/min. He had been abstinent since the diagnosis of cirrhosis a year prior. Laboratory results at admission were: leukocyte count 12.1 G/L, international normalised ratio 2.1, creatinine 2.4 mg/dl, sodium 133 mmol/L, total bilirubin 7 mg/dl, lactate 5.5 mmol/L, with a MELD-Na score of 31 and a CLIF-C ACLF score of 67. On the 7^th day after admission, the patient was placed on the LT waiting list. On the same day, he had massive variceal bleed with hypovolemic shock requiring terlipressin, transfusion of three red blood cell units, and endoscopic band ligation. On day 10, the patient was stabilised with a low dose of norepinephrine 0.03 μg/kg/min, with no new sepsis or bleeding. However, the patient was still intubated for grade 2 hepatic encephalopathy and on renal replacement therapy with a lactate level of 3.1 mmol/L. The patient is currently categorised as having ACLF-3, with five organ failures (liver, kidney, coagulation, circulation, and respiration). Based on the severity of his liver disease and multiorgan failure, the patient is at an exceedingly high risk of death without LT. Is it appropriate to perform LT in such a patient?

Artificial Liver Support with CytoSorb and MARS in Liver Failure: A Retrospective Propensity Matched Analysis

Background: Liver failure represents a life-threatening organ dysfunction with liver transplantation as the only proven curable therapy to date. Liver assist devices have been extensively researched to either bridge such patients to transplantation or promote spontaneous recovery. The aim of our study was to compare two such devices, the Molecular Adsorbent Recirculating System (MARS) and CytoSorb, in patients with liver failure. Methods: We retrospectively included 15 patients who underwent MARS during their intensive care unit stay and matched them to 15 patients who underwent hemoadsorption using CytoSorb. Clinical and paraclinical data obtained after each individual session, after the course of treatment, as well as at the end of the intensive care unit stay were compared between the two groups. Results: Single sessions of CytoSorb and MARS were both associated with a significant decrease in bilirubin (p = 0.04 and p = 0.04, respectively) and ammonia levels (p = 0.04 and p = 0.04, respectively), but only CytoSorb therapy was associated with a decrease in lactate dehydrogenase levels (p = 0.04) and in platelet count (p = 0.04). After the course of treatment, only CytoSorb was associated with a significant decrease in lactate (p = 0.01), bilirubin (p = 0.01), ammonia (p = 0.02), and lactate dehydrogenase levels (p = 0.01), while patients treated with MARS did not show any improvement in paraclinical liver tests. In addition, only CytoSorb treatment was associated with a significant improvement in the Model for End-Stage Liver Disease Score (p = 0.04). Conclusion: In conclusion, our results show a potential benefit of CytoSorb in rebalancing liver functional tests in patients with liver failure compared to MARS but the exact effects on patient outcome, including hospital length of stay and survival, should be further investigated in randomized control trials.

Acute-on-chronic liver failure: clinical course and liver transplantation

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is a clinical syndrome characterized by intense systemic inflammatory response, multiple-organ failures, and high short-term mortality in patients with chronic liver disease. ACLF is dynamic and heterogeneous, and the prognosis is closely related to the clinical course. Currently, liver transplantation (LT) remains the only potential curative treatment that improves survival of ACLF patients.

AREAS COVERED

In this review, we summarize the dynamic clinical course of ACLF and the relationship between the clinical course and the post-LT prognosis, especially the factors affecting the mortality after LT in severe ACLF patients and explore the optimal choice of LT therapy for ACLF patients, both to benefit patients the most and to avoid futile therapy.

EXPERT OPINION

ACLF is a dynamic disease with varying clinical phenotypes, and the global burden is high. Early identification of the clinical course is important to assess the prognosis and guide the treatment. The contradiction between shortage of liver donors and the large number of recipients makes it necessary for us to strictly screen out the recipients and identify patients who really need LT to save liver sources.

Research progress on short-term prognosis of acute-on-chronic liver failure

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is a clinical syndrome characterized as a severe condition with rapid progression, poor therapeutic response and poor prognosis. Early and timely evaluation of the prognosis is helpful for providing appropriate clinical intervention and prolonging patient survival.

AREAS COVERED

Currently, there are no specific dynamic and comprehensive approaches to assess the prognosis of patients with ACLF. This article reviews the progress in evaluating the short-term prognosis of ACLF to provide future directions for more dynamic prospective large-scale multicenter studies and a basis for individualized and precise treatment for ACLF patients. We searched PubMed and Web of Science with the term 'acute on chronic liver failure' and 'prognosis.' There was no date or language restriction, and our final search was on 26 October 2022.

EXPERT OPINION

ACLF is a dynamic process, and the best prognostic marker is the clinical evolution of organ failure over time. New prognostic markers are developing not only in the fields of genetics and histology but also toward diversification combined with imaging. Determining which patients will benefit from continued advanced life support is a formidable challenge, and accurate short-term prognostic assessments of ACLF are a good approach to addressing this issue.

Liver transplantation in Acute-on-Chronic liver failure: Timing of transplantation and selection of patient population

Acute-on-Chronic liver failure (ACLF) is a clinical syndrome with high short-term mortality. Alcoholic ACLF is prevalent in European and American countries, while hepatitis B virus (HBV)-related ACLF is more common in the Asia-Pacific region. There is still a lack of a unified definition standard for ACLF, due to various etiologies and pathogeneses in different continents. Currently, liver transplantation (LT) is the most effective treatment for liver failure. However, the shortage of liver sources is still a global problem, which seriously limits the clinical application of an LT. Premature LT aggravates the shortage of liver resources to a certain extent, and too much delay significantly increases the risk of complications and death. Therefore, this study reviews the current literature on LT in the treatment of ACLF and discusses further the challenges for ACLF patients, the timing of LT for ACLF, and the choice of the patient population.

Liver transplantation is beneficial regardless of cirrhosis stage or acute-on-chronic liver failure grade: A single-center experience

BACKGROUND

Liver transplantation for the most critically ill remains controversial; however, it is currently the only curative treatment option.

AIM

To assess immediate posttransplant outcomes and compare the short (1 year) and long-term (6 years) posttransplant survival among cirrhotic patients stratified by disease severity.

METHODS

We included cirrhotic patients undergoing liver transplantation between 2015 and 2019 and categorized them into compensated cirrhosis (CC), decompensated cirrhosis (DC), and acute-on-chronic liver failure (ACLF). ACLF was further divided into severity grades. Our primary outcomes of interest were total days of intensive care unit (ICU) and hospital stay, development of complications and posttransplant survival at 1 and 6 years.

RESULTS

235 patients underwent liver transplantation (CC = 11, DC = 129 and ACLF = 95). Patients with ACLF had a significantly longer hospital stay [8.0 (6.0-13.0) vs CC, 6.0 (3.0-7.0), and DC 7.0 (4.5-10.0); P = 0.01] and developed more infection-related complications [47 (49.5%), vs CC, 1 (9.1%) and DC, 38 (29.5%); P < 0.01]. Posttransplant survival at 1- and 6-years was similar among groups (P = 0.60 and P = 0.90, respectively). ACLF patients stratified according to ACLF grade [ACLF-1 n = 40 (42.1%), ACLF-2 n = 33 (34.7%) and ACLF-3 n = 22 (23.2%)], had similar ICU and hospital stay length (P = 0.68, P = 0.54), as well as comparable frequencies of overall and infectious post-transplant complications (P = 0.58, P = 0.80). There was no survival difference between ACLF grades at 1 year and 6 years (P = 0.40 and P = 0.15).

CONCLUSION

Patients may benefit from liver transplantation regardless of the cirrhosis stage. ACLF patients have a longer hospital stay and frequency of infectious complications; however, excellent, and comparable 1 and 6-year survival rates support their enlisting and transplantation including those with ACLF-3.

Liver transplantation in patients with acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is a dynamic syndrome associated with a very high short-term mortality. Hence, the ongoing assessment of treatment response, an expedited liver transplant evaluation and listing, and the determination of futility of treatment are critical for optimal outcomes. In this review, we appraise our current understanding of the timing and futility of liver transplantation, and the short- and long-term outcomes including the quality of life after deceased or live donor liver transplantation in those with ACLF.

Liver Transplantation in Acute-on-Chronic Liver Failure: Excellent Outcome and Difficult Posttransplant Course

Background

Acute-on-chronic liver failure (ACLF) patients have high mortality in a short period of time. This study aimed to compare the prognosis of transplanted ACLF patients to that of nontransplanted ACLF patients and decompensated cirrhosis recipients.

Methods

Clinical data of 29 transplanted ACLF patients, 312 nontransplanted ACLF patients, and 60 transplanted decompensated cirrhosis patients were retrospectively collected. Propensity score matching (PSM) analysis was used to match patients between different groups.

Results

After PSM, the 90-day and 1-year survival of transplanted ACLF patients was significantly longer than that of nontransplant controls. Although the 90-day survival and 1-year survival of ACLF recipients was similar to that of decompensated cirrhosis controls, ACLF recipients were found to have longer mechanical ventilation, longer intensive care unit (ICU) stay, longer hospital stay, higher incidence of tracheotomy, higher expense, and higher morbidity of complication than matched decompensated cirrhosis controls. The 90-day and 1-year survival of transplanted ACLF grade 2–3 patients was also significantly longer than that of nontransplanted controls.

Conclusions

Liver transplantation can strongly improve the prognosis of ACLF patients. Despite having more burdens (including longer mechanical ventilation, longer ICU stay, higher incidence of tracheotomy, longer hospital stay, higher hospitalization expense, and higher complication morbidity), ACLF recipients can obtain similar short-term and long-term survival to decompensated cirrhosis recipients. For severe ACLF patients, liver transplantation can also significantly improve their short-term and long-term survival.

High-risk liver transplant recipients with grade 3 acute on chronic liver failure should receive the good quality graft

BACKGROUND & AIM

We aimed to develop a risk score for LT recipients and donor selection among patients with ACLF-3.

METHODS AND RESULTS

A total of 7166 adult LT recipients (mean age 53 years, 63% males, 56% Caucasians, 42% obese, median MELD score 36.5) using deceased donor grafts in the UNOS database (01/2002-06/2018) who were in ACLF-3 at LT as per EASL-CLIF criteria were analysed. Cox regression model on the derivation dataset (N = 3583) showed recipient age, non-alcohol aetiology, pulmonary failure, brain failure and cardiovascular failure to be associated with 1-year patient survival. Observed and expected post-transplant 1-year survival showed excellent correlation (R = .920). Risk score from cox model on derivation dataset stratified 3583 recipients in validation cohort using cut-off scores 7.55 and 11.57 to low (N = 1211), medium (N = 1168) and high risk (N = 1199), with 1-year patient survival of 89%, 82% and 80% respectively. Based on poor versus good quality graft (donor risk index cut-off at 1.50), 1-year patient survival for low, medium and high-risk categories were 90 versus 89% (p = .490), 83 versus 82% (p = .390) and 83 versus 78% (p = .038) respectively. Among recipients with a high-risk score, donor factors of age ≥60 years, grafts obtained from national sharing and macro-steatosis >15% were associated with 1-year patient survival below 66%.

CONCLUSION

Among ACLF-3 liver transplant recipients, those with high risk at the time of transplant receiving better quality graft will improve post-transplant outcomes. Prospective studies using additional characteristics are needed to derive an accurate risk score model in predicting post-transplant outcomes among recipients with ACLF-3.

The use of tracheostomy to support critically ill children receiving orthotopic liver transplantation: a single-center experience

BACKGROUND

Children with end-stage liver disease and multi-organ failure, previously considered as poor surgical candidates, can now benefit from liver transplantation (LT). They often need prolonged mechanical ventilation (MV) post-LT and may need tracheostomy to advance care. Data on tracheostomy after pediatric LT are lacking.

METHOD

Retrospective chart review of children who required tracheostomy in the peri-LT period in a large, freestanding quaternary children's hospital from 2014 to 2019.

RESULTS

Out of 205 total orthotopic LTs performed in 200 children, 18 (9%) required tracheostomy in the peri-transplant period: 4 (2%) pre-LT and 14 (7%) post-LT. Among those 14 needing tracheostomy post-LT, median age was 9 months [IQR = 7, 14] at LT and 10 months [9, 17] at tracheostomy. Nine (64%) were infants and 12 (85%) were cirrhotic at the time of LT. Seven (50%) were intubated before LT. Median MV days prior to LT was 23 [7, 36]. Eight (57%) patients received perioperative continuous renal replacement therapy (CRRT). The median MV days from LT to tracheostomy was 46 [33, 56]; total MV days from initial intubation to tracheostomy was 57 [37, 66]. Four (28%) children died, of which 3 (21%) died within 1 year of transplant. Total ICU and hospital length of stay were 92 days [I72, 126] and 177 days [115, 212] respectively. Among survivors, 3/10 (30%) required MV at home and 8/10 (80%) were successfully decannulated at 400 median days [283, 584].

CONCLUSION

Tracheostomy though rare after LT remains a feasible option to support and rehabilitate critically ill children who need prolonged MV in the peri-LT period.

Immunosuppression in patients with Grade 3 Acute-On-Chronic Liver Failure at transplantation: A practice analysis study

Transplantation for patients with acute-on-chronic liver failure grade 3 (ACLF3) has encouraging results with one-year-survival of 80-90%. These patients with multiple organ failure meet the conditions for serious alterations of drug metabolism and increased toxicity. The goal of this study was to identify immunosuppression-dependent factors that affect survival. This retrospective monocentric study was conducted in patients with ACLF3 consecutively transplanted between 2007 and 2019. The primary endpoint was one-year survival. Secondary endpoints were overall survival, treated rejection and surgical complications. Immunosuppression was evaluated as to type of immunosuppression, post-transplant introduction timing, through levels and trough level intra-patient variability (IPV). One hundred patients were included. Tacrolimus IPV <40% (p=0.019), absence of early tacrolimus overdose (p=0.033), use of anti-IL2-receptor antibodies (p=0.034) and early mycophenolic acid introduction (p=0.038) predicted one-year survival. Treated rejection was an independent predictor of survival (p=0.001; HR 4.2 (CI 95%: 1.13-15.6)). Early everolimus introduction was neither associated with higher rejection rates nor with more surgical complications. Management of immunosuppression in ACLF3 critically ill patients undergoing liver transplantation is challenging. Occurrence and treatment of rejection impacts on survival. Early introduction of mTOR inhibitor seems safe and efficient in this situation. This article is protected by copyright. All rights reserved.

Novel drug discovery strategies for the treatment of decompensated cirrhosis

INTRODUCTION

Disease progression in cirrhosis leads to decompensation and acute-on-chronic liver failure (ACLF), which is characterized by organ failure and high mortality. Portal hypertension and cardiovascular dysfunction trigger the development of cirrhosis-related complications whilst tissue injury and cellular metabolic dysfunction lead to organ failure. System inflammation is the overarching mechanism mediating both the transition from compensation to decompensation as well as progression to ACLF. Treatment of precipitating events and intensive organ support is the only established therapeutic strategies. Liver transplantationrepresents the only curative therapy but contraindications and organ scarcity limit its availability to only a minority of patients with end-stage liver disease. Therefore, the discovery and development of novel interventions modifying the disease course and improving patients' outcome are of utmost importance.

AREAS COVERED

This review highlights and discusses therapeutic novelties in the field of end-stage liver disease.

EXPERT OPINION

Despite decades of research, there are still no established therapies to improve the devastating prognosis of patients with end-stage liver disease. The clinical heterogeneity and complex pathogenesis will put high demands on drug discovery. Combinatorial therapies tailored to the patients' individual pattern of pathomechanisms may be the most efficient way to modify disease course.

Early transplantation maximizes survival in severe acute-on-chronic liver failure: Results of a Markov decision process model

Background & Aims

Uncertainties exist surrounding the timing of liver transplantation (LT) among patients with acute-on-chronic liver failure grade 3 (ACLF-3), regarding whether to accept a marginal quality donor organ to allow for earlier LT or wait for either an optimal organ offer or improvement in the number of organ failures, in order to increase post-LT survival.

Methods

We created a Markov decision process model to determine the optimal timing of LT among patients with ACLF-3 within 7 days of listing, to maximize overall 1-year survival probability.

Results

We analyzed 6 groups of candidates with ACLF-3: patients age ≤60 or >60 years, patients with 3 organ failures alone or 4-6 organ failures, and hepatic or extrahepatic ACLF-3. Among all groups, LT yielded significantly greater overall survival probability vs. remaining on the waiting list for even 1 additional day (p <0.001), regardless of organ quality. Creation of 2-way sensitivity analyses, with variation in the probability of receiving an optimal organ and expected post-transplant mortality, indicated that overall survival is maximized by earlier LT, particularly among candidates >60 years old or with 4-6 organ failures. The probability of improvement from ACLF-3 to ACLF-2 does not influence these recommendations, as the likelihood of organ recovery was less than 10%.

Conclusion

During the first week after listing for patients with ACLF-3, earlier LT in general is favored over waiting for an optimal quality donor organ or for recovery of organ failures, with the understanding that the analysis is limited to consideration of only these 3 variables.

Lay summary

In the setting of grade 3 acute-on-chronic liver failure (ACLF-3), questions remain regarding the timing of transplantation in terms of whether to proceed with liver transplantation with a marginal donor organ or to wait for an optimal liver, and whether to transplant a patient with ACLF-3 or wait until improvement to ACLF-2. In this study, we used a Markov decision process model to demonstrate that earlier transplantation of patients listed with ACLF-3 maximizes overall survival, as opposed to waiting for an optimal donor organ or for improvement in the number of organ failures.

Excellent Outcome in Living Donor Liver Transplantation: Treating Patients With Acute-on-Chronic Liver Failure

Acute-on-chronic liver failure (ACLF) is a fatal condition, and liver transplantation (LT) is a vital option for these patients. However, the result of living donor LT (LDLT) for ACLF is not well investigated. This study investigated the outcomes of LDLT in patients with ACLF compared with patients without ACLF. This was a single-center, retrospective, matched case-control study. From July 2002 to March 2017, a total of 112 patients with ACLF who underwent LDLT were enrolled according to the consensus of the Asian Pacific Association for the Study of the Liver. A total of 224 patients were selected for control comparison (non-ACLF) with demographic factors (sex, age, and body mass index) matched (1:2). Patients with ACLF were stratified into ACLF 1, 2, and 3 categories according to the number of organ failures based on the Chronic Liver Failure-Sequential Organ Failure Assessment score. Survival and surgical outcomes after LDLT were analyzed. The Model for End-Stage Liver Disease and Child-Turcotte-Pugh scores in the ACLF group were significantly higher than those in the non-ACLF group (P < 0.001). The 90-day, 3-year, and 5-year survival rates in the ACLF and non-ACLF groups were 97.3%, 95.5%, 92.9%, respectively, and 96.9%, 94.2%, and 91.1%, respectively (P = 0.58). There was more intraoperative blood loss in the ACLF group than in the non-ACLF group (P < 0.001). The other postoperative complications were not significantly different between the groups. A total of 20 patients (17.9%) in the ACLF group presented with 3 or more organ system dysfunctions (ACLF 3), and the 90-day, 3-year, and 5-year survival rates were comparable with those of ACLF 1 and ACLF 2 (P = 0.25). In carefully selected patients, LDLT gives excellent outcomes in patients with ACLF regardless of the number of organs involved. Comprehensive perioperative care and timely transplantation play crucial roles in saving the lives of patients with ACLF.

New Indications for Liver Transplantation

Liver transplantation (LT) is an important therapeutic option for the treatment of several liver diseases. Modern LT is characterized by remarkable improvements in post-transplant patient survival, graft survival, and quality of life. Thanks to these great improvements, indications for LT are expanding. Nowadays, clinical conditions historically considered exclusion criteria for LT, have been considered new indications for LT, showing survival advantages for patients. In this review, we provide an updated overview of the principal newer indications for LT, with particular attention to alcoholic hepatitis, acute-on-chronic liver failure (ACLF), cholangiocarcinoma and colorectal cancer metastases.

Predictors and outcome of emergent Liver transplantation for patients with acute-on-chronic liver failure

BACKGROUND AND AIMS

Controversy exists over whether emergent liver transplantation (LT) should be performed for patients with acute-on-chronic liver failure (ACLF), especially for patients with multiple organ failure.

METHODS

A total of 110 ACLF patients, defined by the European Association for the Study of the Liver (EASL) Chronic Liver Failure-Sequential Organ Failure Assessment (CLIF-SOFA) criteria were analyzed. The primary outcome was overall survival after ACLF diagnosis.

RESULTS

During follow-up, 76 patients received LT (59 received deceased-donor LT and 17 patients received living-donor LT). The overall survival was better for patients who received LT than patients who did not (82.9% vs. 17.6%, P < 0.001). Among the 76 patients who received LT, the overall survival was not different according to ACLF grade at diagnosis (70.0%, 85.3%, and 84.4% at one-year for ACLF grades 1, 2, and 3, respectively, P = 0.45). The baseline model for end-stage liver disease (MELD) score and progression of the ACLF grade during the pre-transplant period were independent factors for survival after LT. The one-year survival rate was 92.3% for patients with baseline MELD scores of ≤ 32 without ACLF grade progression, whereas it was 33.3% for those with baseline MELD scores of > 32 and ACLF grade progression.

CONCLUSIONS

Emergent LT provided a significant survival benefit to ACLF patients, regardless of the baseline ACLF grade. Post-LT outcomes were associated with baseline MELD scores and ACLF progression during the pre-transplant period, which might be used in the emergent LT plan for patients presenting with ACLF.

Liver Transplantation in Acute-on-chronic Liver Failure

Liver transplantation (LT) has revolutionized outcomes for cirrhotic patients. Current liver allocation policies dictate patients with highest short-term mortality receive the highest priority, thus, several patients become increasingly ill on the waitlist. Given cirrhosis is a progressive disease, it can be complicated by the occurrence of acute-on-chronic liver failure (ACLF), a syndrome defined by an acute deterioration of liver function associated with extrahepatic organ failures requiring intensive care support and a high short-term mortality. Successfully bridging to transplant includes accurate prognostication and prioritization of ACLF patients awaiting LT, optimizing intensive care support pre-LT, and tailoring immunosuppressive and anti-infective therapies post-LT. Furthermore, predicting futility (too sick to undergo LT) in ACLF is challenging. In this review, we summarize the role of LT in ACLF specifically highlighting (a) current prognostic scores in ACLF, (b) critical care management of the ACLF patient awaiting LT, (c) donor issues to consider in transplant in ACLF, and (d) exploring of recent post-LT outcomes in ACLF and potential opportunities to improve outcomes including current care gaps and unmet research needs.

When Is a Critically Ill Cirrhotic Patient Too Sick to Transplant? Development of Consensus Criteria by a Multidisciplinary Panel of 35 International Experts

BACKGROUND

Critically ill cirrhotic patients are increasingly transplanted, but there is no consensus about futile liver transplantation (LT). Therefore, the decision to delay or deny LT is often extensively debated. These debates arise from different opinions of futility among transplant team members. This study aims to achieve a multinational and multidisciplinary consensus on the definition of futility in LT and to develop well-articulated criteria for not proceeding with LT due to futility.

METHODS

Thirty-five international experts from anesthesiology/intensive care, hepatology, and transplant surgery were surveyed using the Delphi method. More than 70% of similar answers to a question were necessary to define agreement.

RESULTS

The panel recommended patient and graft survival at 1 year after LT to define futility. Severe frailty and persistent fever or <72 hours of appropriate antimicrobial therapy in case of ongoing sepsis were considered reasons to delay LT. A simple assessment of the number of organs failing was considered the most appropriate way to decide whether LT should be delayed or denied, with respiratory, circulatory and metabolic failures having the most influence in this decision. The thresholds of severity of organ failures contraindicating LT for which a consensus was achieved were a Pao2/FiO2 ratio<150 mm Hg, a norepinephrine dose >1 μg/kg per minute and a serum lactate level >9 mmol/L.

CONCLUSIONS

Our expert panel provides a consensus on the definition of futile LT and on specific criteria for postponing or denying LT. A framework that may facilitate the decision if a patient is too sick for transplant is presented.

Limitations of current liver donor allocation systems and the impact of newer indications for liver transplantation

Liver transplantation represents a life-saving treatment for patients with decompensated cirrhosis, a severe condition associated with a high risk of waiting list mortality. When decompensation occurs rapidly in the presence of extrahepatic organ failures, the condition is called acute-on-chronic liver failure, which is associated with an even higher risk of death, though liver transplantation can also markedly improve survival in affected patients. However, there are still gaps in our understanding of how to optimise prioritisation and organ allocation, as well as survival among patients with acute-on-chronic liver failure (both before and after transplant). Moreover, it is urgent to address inequalities in access to liver transplantation in patients with severe alcoholic hepatitis and non-alcoholic steatohepatitis. Several controversies still exist regarding gender and regional disparities, as well as the use of suboptimal donor grafts. In this review, we aim to provide a critical perspective on the role of liver transplantation in patients with decompensated cirrhosis and address areas of ongoing uncertainty.

Liver transplantation for acute-on-chronic liver failure predicts post-transplant mortality and impaired long-term quality of life

BACKGROUND

Among patients with cirrhosis, candidate selection and timing of liver transplantation (LT) remain problematic. Acute-on-chronic liver failure (ACLF) is a severe complication of cirrhosis with excessive short-term mortality rates under conservative therapeutic measures. The role of LT in the management of ACLF is uncertain.

OBJECTIVE

To assess the impact of ACLF on post-LT survival and long-term graft function, morbidity and quality of life (QoL).

METHODS

We retrospectively analysed all cirrhosis patients undergoing LT at our institution between 01/2009 and 12/2014. Median follow-up was 8.7 years. Long-term LT survivors were interviewed with established QoL questionnaires.

RESULTS

Of 250 LT recipients, 98 fulfilled the EASL diagnostic ACLF criteria before LT ('ACLF-LT'). ACLF associated with reduced post-LT survival (HR for 6-month survival compared to non-ACLF-LT: 0.18; HR for 10-year-survival: 0.47; both P < .001) depending on ACLF severity before LT, and mainly inferred by infections both in the early and late phases after LT. In ACLF patients, CLIFc-OFs was superior to MELD score in predicting post-LT mortality. Long-term follow-up revealed comparable graft functions and comorbidity burden in ACLF-LT and non-ACLF-LT survivors. ACLF-LT patients reported significantly impaired health and QoL, particularly with regards to anxiety/depression and physical and psychological health (all P < .05). LabMELD score, presence of ACLF at LT and duration of post-LT intensive care associated with poor long-term QoL.

CONCLUSION

ACLF predicts impaired post-LT survival. While long-term graft function and extrahepatic comorbidities are comparable in ACLF and non-ACLF LT survivors, the strikingly low QoL in many ACLF-LT recipients warrants consideration during follow-up patient care.

Expanding Indications of Liver Transplantation in Spain: Consensus Statement and Recommendations by the Spanish Society of Liver Transplantation

BACKGROUND

The number of patients awaiting liver transplantation (LT) in Spain has halved from 2015 to 2019 due to the reduction of candidates with hepatitis C and the successful implementation of nonheart beating donation programs across the country. The Spanish Society for Liver Transplantation has committed to take advantage of this situation by developing consensus around potential areas to expand the current indications for LT. The consensus group was composed of 6 coordinators and 23 expert delegates, each one representing an LT institution in Spain.

METHODS

A modified Delphi approach was used to identify areas to expand indications for LT and to build consensus around paramount aspects, such as inclusion criteria and waitlist prioritization within each area. The scientific evidence and strength of recommendations were assessed by the "Grading of Recommendations Assessment, Development, and Evaluation" system.

RESULTS

The consensus process resulted in the identification of 7 potential areas to expand criteria in LT: recipient's age, hepatocellular carcinoma, alcoholic hepatitis, acute-on-chronic liver failure, hilar and intrahepatic cholangiocarcinoma, and unresectable liver metastases of colorectal cancer.

CONCLUSIONS

We present the main recommendations issued for each topic, together with their core supporting evidence. These recommendations may allow for expanding criteria for LT homogenously in Spain and may provide a guidance to other countries/institutions facing a similar scenario.

Clinical Impacts and Outcomes With Possible Donor-Derived Infection in Infected Donor Liver Transplantation: A Single-Center Retrospective Study in China

BACKGROUND

Information on possible donor-derived transmission events in China is limited. We evaluated the impacts of liver transplantation from infected deceased-donors, analyzed possible donor-derived bacterial or fungal infection events in recipients, and evaluated the etiologic agents' characteristics and cases outcomes.

METHODS

A single-center observational study was performed from January 2015 to March 2017 to retrospectively collect data from deceased-donors diagnosed with infection. Clinical data were recorded for each culture-positive donor and the matched liver recipient. The microorganisms were isolated and identified, and antibiotic sensitivity testing was performed. The pathogens distribution and incidence of possible donor-derived infection (P-DDI) events were analyzed and evaluated.

RESULTS

Information from 211 donors was collected. Of these, 82 donors were infected and classified as the donation after brain death category. Overall, 149 and 138 pathogens were isolated from 82 infected donors and 82 matched liver recipients, respectively. Gram-positive bacteria, Gram-negative bacteria, and fungi accounted for 42.3% (63 of 149), 46.3% (69 of 149), and 11.4% (17 of 149) of pathogens in infected donors. The incidence of multidrug-resistant bacteria was high and Acinetobacter baumannii was the most concerning species. Infections occurred within the first 2 weeks after liver transplantation with an organ from an infected donor. Compared with the noninfection recipient group, the infection recipient group experienced a longer mechanical ventilation time (P = .004) and intensive care unit stay (P = .003), a higher incidence of renal dysfunction (P = .026) and renal replacement therapy (P = .001), and higher hospital mortality (P = .015). Possible donor-derived infection was observed in 14.6% of cases. Recipients with acute-on-chronic liver failure were more prone to have P-DDI than recipients with other diseases (P = .007; odds ratio = 0.114; 95% confidence interval, .025-.529).

CONCLUSIONS

When a liver recipient receives a graft from an infected deceased-donor, the postoperative incidence of infection is high and the infection interval is short. In addition, when a possible donor-derived, drug-resistant bacterial infection occurs, recipients may have serious complications and poor outcomes.

Longterm Outcomes of Patients Undergoing Liver Transplantation for Acute-on-Chronic Liver Failure

Recent data have demonstrated >80% 1-year survival probability after liver transplantation (LT) for patients with severe acute-on-chronic liver failure (ACLF). However, longterm outcomes and complications are still unknown for this population. Our aim was to compare longterm patient and graft survival among patients transplanted across all grades of ACLF. We analyzed the United Network for Organ Sharing database for the years 2004-2017. Patients with ACLF were identified using the European Association for the Study of the Liver-Chronic Liver Failure criteria. Kaplan-Meier and Cox regression methods were used to determine patient and graft survival and associated predictors of mortality in adjusted models. A total of 56,801 patients underwent transplantation of which 31,024 (54.6%) had no ACLF, 8757 (15.4%) had ACLF grade 1, 9039 (15.9%) had ACLF grade 2, and 7891 (14.1%) had ACLF grade 3. The 5-year patient survival after LT was lower in the ACLF grade 3 patients compared with the other groups (67.7%; P < 0.001), although after year 1, the percentage decrease in survival was similar among all groups. Infection was the primary cause of death among all patient groups in the first year. Infection was the primary cause of death among all patient groups in the first year. After the first year, infection was the main cause of death in patients transplanted with ACLF grade 1 (32.1%), ACLF grade 2 (33.9%), and ACLF grade 3 (37.6%), whereas malignancy was the predominant cause of death in those transplanted with no ACLF (28.5%). In conclusion, patients transplanted with ACLF grade 3 had lower 5-year survival as compared with patients with ACLF grades 0-2, but mortality rates were not significantly different after the first year following LT. Graft survival was excellent across all ACLF groups.

[Liver transplantation - current trends]

INDICATION OF TRANSPLANTATION

There is an ongoing change in the indications of orthotopic liver transplantation (OLT) with non-alcoholic and alcoholic liver disease and hepatocellular carcinoma (HCC) becoming the main indications whereas the numbers of cirrhosis due to chronic viral hepatitis are declining. 6-MONTH ABSTINENCE RULE: : The directive of the German Federal Medical Association requires absolute abstinence from alcohol for at least 6 months. New data show that patients with severe alcoholic hepatitis for the first time who do not show a response to medical treatment may benefit from OLT. For these patients an individual exception for OLT listing can be requested.

HCC BEYOND MILAN CRITERIA

New data show that patients with HCC outside the Milan criteria may have a favorable prognosis, which can be comparable to patients with HCC within the Milan criteria, if effective pre-transplant "down-staging" therapies but also alfa fetoprotein levels are taken into consideration. TOO SICK TO TRANSPLANT?:  Even patients with decompensated cirrhosis and multi-organ dysfunction, defined as acute-on-chronic liver failure, may undergo OLT successfully with a beneficial long-term prognosis. However, the timeframe to realize OLT is short.

ORGAN SHORTAGE

OLT using organs from HBV- or HCV-infected patients represents a relevant strategy to mitigate organ shortage and can be safely and effectively be performed due to the excellent therapeutic options against these infections which are available now. In addition, machine perfusion, a novel tool for organ conservation and conditioning, may help preserving organs for transplantation that formerly could not be used.

Acute on Chronic Liver Failure: Definition and Implications

Acute on chronic liver failure (ACLF) is an inflammation-based disorder that occurs in patients with underlying liver disease and is characterized by hepatic and extrahepatic organ failure. Morbidity and mortality are high in patients with ACLF, and therefore prevention and early identification are critical to improve outcome. The purpose of this article is to define ACLF, describe ways to identify the expected outcome of ACLF after development, and illustrate interventions to prevent it and when it is not preventable reduce associated morbidity and mortality.

Systematic review with meta-analysis: liver transplant provides survival benefit in patients with acute on chronic liver failure

BACKGROUND

Data on liver transplantation (LT) in acute on chronic liver failure (ACLF) are scanty.

AIM

To perform meta-analysis on outcomes after LT for ACLF compared with ACLF patients not receiving LT or with LT recipients for indications other than ACLF.

METHODS

We pooled data from 12 studies on LT outcomes among ACLF patients.

RESULTS

Among nine studies, 22 238 LT recipients for ACLF vs 30 791 for non-ACLF were younger by 1.1 years, less males (64% vs 66.4%), and higher model for end-stage disease score by 14.5 (14.4-14.6), P < 0.01 for all. Post-transplant patient survival at 30 day, 90 day, 6 months, 1 year and 5 years was lower in ACLF: 96.2% vs 98.1%, 92.6% vs 96.2%, 89.9% vs 94.4%, 86.0% vs 91.9%, 66.9% vs 80.7% respectively, P < 0.01 for all. ACLF patients stayed longer in hospital and ICU by 5.7 and 10.5 days respectively, P < 0.001, with similar post-transplant complications [74.4% vs 55.5%, P = 0.12]. Among three studies, 441 LT recipients for ACLF vs 301 ACLF patients not selected for LT had better 30 day and 1 year survival: 95.2% vs 60% and 85.3% vs 28.2% respectively, P < 0.001. Outcomes were worse in ACLF-3 and better for ACLF-1 and ACLF-2 patients at the time of LT.

CONCLUSION

In this pooled analysis with a large sample size across the globe, LT for select patients with ACLF provided survival benefit. However, larger prospective studies are needed to further refine selection criteria, especially for ACLF-3 patients as basis for improving outcomes and optimal utilisation of scarce donor pool.

Liver Transplantation for Acute-on-Chronic Liver Failure: Science or Fiction?

Acute clinical deterioration of a patient with chronic liver disease remains a decisive time point both in terms of medical management and prognosis. This condition, also known as acute decompensation (AD), is an important event determining a crossroad in the trajectory of patients. A significant number of patients with AD may develop hepatic or extrahepatic organ failure, or both, which defines the syndrome acute-on-chronic liver failure (ACLF), and ACLF is associated with a high morbidity and short-term mortality. ACLF may occur at any phase during chronic liver disease and is pathogenetically defined by systemic inflammation and immune metabolic dysfunction. When organ failures develop in the presence of cirrhosis, especially extrahepatic organ failures, liver transplantation (LT) may be the only curative treatment. This review outlines the evidence supporting LT in ACLF patients, highlighting the role of timing, bridging to LT, and possible indicators of futility. Importantly, prospective studies on ACLF and transplantation are urgently needed.

Early Transplantation in Acute on Chronic Liver Failure: Who and When

Purpose of Review

Acute on chronic liver failure (ACLF) is a unique syndrome that afflicts patients with chronic liver disease and results in high short-term mortality, > 50% at 28 days in patients with severe ACLF (grade 3, ACLF-3). Given this prognosis, there is an urgent need to understand risk factors for this condition, as well as selection criteria for patients who may benefit from liver transplantation (LT).

Recent Findings

Several studies have identified risk factors for developing ACLF, including higher model for end-stage liver disease score, anemia, and morbid obesity, as well ACLF mortality, such as infection, increasing organ failures, and higher white blood cell count. Prognostic tools are now available as online calculators. Regarding LT in ACLF, data suggest that even patients with ACLF-3 may do well after LT, with 1-year survival > 80% in several studies. Improvement in organ failures prior to LT, higher donor quality, and lack of mechanical ventilation further improve outcomes. Importantly, ACLF-3 patients may have higher short-term wait list mortality than patients listed status-1a, suggesting that increased LT prioritization may be warranted.

Summary

ACLF is a high-mortality condition that frequently responds well to LT. Ongoing efforts to understand the natural history of ACLF and predictors of improved post-LT survival will facilitate LT criteria for this condition, which may ultimately include increased LT prioritization for selected patients.

Effect of the clinical course of acute-on-chronic liver failure prior to liver transplantation on post-transplant survival

BACKGROUND & AIMS

Patients with acute-on-chronic liver failure (ACLF) can be listed for liver transplantation (LT) because LT is the only curative treatment option. We evaluated whether the clinical course of ACLF, particularly ACLF-3, between the time of listing and LT affects 1-year post-transplant survival.

METHODS

We identified patients from the United Network for Organ Sharing database who were transplanted within 28 days of listing and categorized them by ACLF grade at waitlist registration and LT, according to the EASL-CLIF definition.

RESULTS

A total of 3,636 patients listed with ACLF-3 underwent LT within 28 days. Among those transplanted, 892 (24.5%) recovered to no ACLF or ACLF grade 1 or 2 (ACLF 0-2) and 2,744 (75.5%) had ACLF-3 at transplantation. One-year survival was 82.0% among those transplanted with ACLF-3 vs. 88.2% among those improving to ACLF 0-2 (p <0.001). Conversely, the survival of patients listed with ACLF 0-2 who progressed to ACLF-3 at LT (n = 2,265) was significantly lower than that of recipients who remained at ACLF 0-2 (n = 17,631) at the time of LT (83.8% vs. 90.2%, p <0.001). Cox modeling demonstrated that recovery from ACLF-3 to ACLF 0-2 at LT was associated with reduced 1-year mortality after transplantation (hazard ratio0.65; 95% CI 0.53-0.78). Improvement in circulatory failure, brain failure, and removal from mechanical ventilation were also associated with reduced post-LT mortality. Among patients >60 years of age, 1-year survival was significantly higher among those who improved from ACLF-3 to ACLF 0-2 than among those who did not.

CONCLUSIONS

Improvement from ACLF-3 at listing to ACLF 0-2 at transplantation enhances post-LT survival, particularly in those who recovered from circulatory or brain failure, or were removed from the mechanical ventilator. The beneficial effect of improved ACLF on post-LT survival was also observed among patients >60 years of age.

LAY SUMMARY

Liver transplantation (LT) for patients with acute-on-chronic liver failure grade 3 (ACLF-3) significantly improves survival, but 1-year survival probability after LT remains lower than the expected outcomes for transplant centers. Our study reveals that among patients transplanted within 28 days of waitlist registration, improvement of ACLF-3 at listing to a lower grade of ACLF at transplantation significantly enhances post-transplant survival, even among patients aged 60 years or older. Subgroup analysis further demonstrates that improvement in circulatory failure, brain failure, or removal from mechanical ventilation have the strongest impact on post-transplant survival.

Liver transplantation for acute-on-chronic liver failure

Acute-on-chronic liver failure (AoCLF) represents a newly defined entity in patients with liver disease leading to multiple organ failures and increased mortality. To date, no universally accepted definition exists, and different academic societies developed guidelines on the early diagnosis and classification of AoCLF. Recently published trials focused on factors associated with a poor outcome and on the development of severity scores aimed to identify patients who may benefit for advanced monitoring and treatment. No specific therapies are demonstrated to improve survival, and liver transplantation (LT) remains the only treatment associated with improved outcome. Our review focuses on current evidence for early diagnosis and prognostication of disease in patients with AoCLF, as well of criteria for intensive care unit admission, indication, and futility markers of LT, as well as bridging therapy and optimal timing of surgery.

Quantitative Identification of Urban Functions with Fishers’ Exact Test and POI Data Applied in Classifying Urban Districts: A Case Study within the Sixth Ring Road in Beijing

Urban areas involve different functions that attract individuals and fit personal needs. Understanding the distribution and combination of these functions in a specific district is significant for urban development in cities. Many researchers have already studied the methods of identifying the dominant functions in a district. However, the degree of collection and the representativeness of a function in a district are controlled not only by its number in the district but also by the number outside this district and a number of other functions. Thus, this study proposed a quantitative method to identify urban functions, using Fisher’s exact test and point of interest (POI) data, applied in determining the urban districts within the Sixth Ring Road in Beijing. To begin with, we defined a functional score based on three statistical features: the p-value, odds-ratio, and the frequency of each POI tag. The p-value and odds-ratio resulted from a statistical significance test, the Fisher’s exact test. Next, we ran a k-modes clustering algorithm to classify all urban districts in accordance with the score of each function and their combination in one district, and then we detected four different groups, namely, Work and Tourism Mixed-developed district, Mixed-developed Residential district, Developing Greenland district, and Mixed Recreation district. Compared with the other identifying methods, our method had good performance in identifying functions, except for transportation. In addition, the Coincidence Degree was used to evaluate the accuracy of classification. In our study, the total accuracy of identifying urban districts was 83.7%. Overall, the proposed identifying method provides an additional method to the various methods used to identify functions. Additionally, analyzing urban spatial structure can be simpler, which has certain theoretical and practical value for urban geospatial planning.

Impact of acute-on-chronic liver failure on post-transplant survival and on kidney outcomes

OBJECTIVES

We aimed to evaluate the effect of acute-on-chronic liver failure (ACLF) on patients' 1-year post-liver transplant (LT) survival. In addition, we evaluated the effect of ACLF on the development of post-LT chronic kidney disease (CKD) and early allograft dysfunction (EAD).

PATIENTS AND METHODS

A retrospective cohort of patients who underwent transplantation from 2010 to 2016 was studied. EASL-CLIF's definition of ACLF was used. The risk of post-LT death, CKD, and EAD was estimated with regression models weighted by inverse probability weighting considering the recipients' characteristics. Donor's BMI and donor risk index were included in the models as well.

RESULTS

A total of 185 patients were included: 125 (67.6%) without ACLF and 60 (32.4%) with ACLF. The 1-year post-LT survival rate was 91.2% [95% confidence interval (CI): 84.6-95.1%] in patients without ACLF versus 84.9% (95% CI: 73.1-91.9%) in patients with ACLF. Post-LT CKD occurred in 43 (38.7%) patients without ACLF versus 26 (52.0%) patients with ACLF. EAD occurred in 40 (32.3%) patients without ACLF versus 15 (28.8%) patients with ACLF. No effect of ACLF was found on survival (hazard ratio 1.75; 95% CI: 0.64-4.75, P = 0.272), CKD (odds ratio: 1.31; 95% CI: 0.60-2.86; P = 0.491), or EAD (odds ratio: 0.74; 95% CI: 0.38-1.66, P = 0.473).

CONCLUSION

In this study, which included mainly patients with grade 1 ACLF at the time of LT, its presence had no impact on post-LT survival or on the occurrence of CKD or EAD.

Patients With Acute on Chronic Liver Failure Grade 3 Have Greater 14-Day Waitlist Mortality Than Status-1a Patients

Patients listed for liver transplantation (LT) as status 1a currently receive the highest priority on the waiting list. The presence of acute on chronic liver failure (ACLF) with three or more organs failing (ACLF-3) portends low survival without transplantation, which may not be reflected by the Model for End-Stage Liver Disease-Sodium (MELD-Na) score. We compared short-term waitlist mortality for patients listed status 1a and those with ACLF-3 at listing. Data were analyzed from the United Network for Organ Sharing database, years 2002-2014, for 3,377 patients listed status 1a and 5,099 patients with ACLF-3. Candidates with ACLF were identified based on the European Association for the Study of the Liver Chronic Liver Failure Consortium criteria. MELD-Na score was treated as a categorical variable of scores <36, 36-40, and >40. We used competing risks regression to assess waitlist mortality risk. Evaluation of outcomes through 21 days after listing demonstrated a rising trend in mortality among ACLF-3 patients at 7 days (18.0%), 14 days (27.7%), and 21 days (32.7%) (P < 0.001) compared to a stable trend in mortality among individuals listed as status 1a at 7 days (17.9%), 14 days (19.3%), and 21 days (19.8%) (P = 0.709). Multivariable modeling with adjustment for MELD-Na category revealed that patients with ACLF-3 had significantly greater mortality (subhazard ratio, 1.45; 95% confidence interval, 1.31-1.61) within 14 days of listing compared to status-1a candidates. Analysis of the interaction between MELD-Na category and ACLF-3 showed that patients with ACLF-3 had greater risk of 14-day mortality than status-1a-listed patients, across all three MELD-Na categories. Conclusion: Patients with ACLF-3 at the time of listing have greater 14-day mortality than those listed as status 1a, independent of MELD-Na score; these findings illustrate the importance of early transplant evaluation and consideration of transplant priority for patients with ACLF-3.

Approaches for patients with very high MELD scores

In the era of the “sickest first” policy, patients with very high model for end-stage liver disease (MELD) scores have been increasingly admitted to the intensive care unit with the expectation that they will receive a liver transplant (LT) in the absence of improvement on supportive therapies. Such patients are often admitted in a context of acute-on-chronic liver failure with extrahepatic failures. Sequential assessment of scores or classification based on organ failures within the first days after admission help to stratify the risk of mortality in this population. Although the prognosis of severely ill cirrhotic patients has recently improved, transplant-free mortality remains high. LT is still the only curative treatment in this population. Yet, the increased relative scarcity of graft resource must be considered alongside the increased risk of losing a graft in the initial postoperative period when performing LT in “too sick to transplant” patients. Variables associated with poor immediate post-LT outcomes have been identified in large studies. Despite this, the performance of scores based on these variables is still insufficient. Consideration of a patient’s comorbidities and frailty is an appealing predictive approach in this population that has proven of great value in many other diseases. So far, local expertise remains the last safeguard to LT. Using this expertise, data are accumulating on favourable post-LT outcomes in very high MELD populations, particularly when LT is performed in a situation of stabilization/improvement of organ failures in selected candidates. The absence of “definitive” contraindications and the control of “dynamic” contraindications allow a “transplantation window” to be defined. This window must be identified swiftly after admission given the poor short-term survival of patients with very high MELD scores. In the absence of any prospect of LT, withdrawal of care could be discussed to ensure respect of patient life, dignity and wishes.