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

Liver transplantation for acute liver failure and acute-on-chronic liver failure

Acute liver failure (ALF) and acute-on-chronic liver (ACLF) are distinct phenotypes of liver failure and, thus, need to be compared and contrasted for appropriate management. There has been a significant improvement in the outcomes of these patients undergoing liver transplantation (LT). Survival post-LT for ALF and ACLF ranges between 90% and 95% and 80% and 90% at 1 year, futility criteria have been described in both ALF and ACLF where organ failures define survival. Plasma exchange and continuous renal replacement therapy may serve as bridging therapies. Identifying the futility of LT is as necessary as the utility of LT in patients with ALF and ACLF. The role of regenerative therapies such as granulocyte colony-stimulating factors in ACLF and hepatocyte and xenotransplantation in both conditions remains uncertain. Measures to increase the donor pool through increasing deceased donor transplants in Asian countries, living donations in Western countries, auxiliary liver transplants, and ABO-incompatible liver transplants are necessary to improve the survival of these patients. In this review, we discuss the similarities and differences in clinical characteristics and the timing and outcomes of LT for ALF and ACLF, briefly highlighting the role of bridging therapies and providing an overview of recent advances in the management of ALF and ACLF.

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.

Enhancing ACLF prediction by integrating sarcopenia assessment and frailty in liver transplant candidates on the waiting list

Background & Aims

Malnutrition, sarcopenia, and frailty are prevalent in cirrhosis. We aimed to assess the correlation between assessment tools for malnutrition, sarcopenia, and frailty in patients on the liver transplant (LT) waiting list (WL), and to identify a predictive model for acute-on-chronic liver failure (ACLF) development.

Methods

This prospective single-center study enrolled consecutive patients with cirrhosis on the WL for LT (May 2019-November 2021). Assessments included subjective global assessment, CT body composition, skeletal muscle index (SMI), ultrasound thigh muscle thickness, sarcopenia HIBA score, liver frailty index (LFI), hand grip strength, and 6-minute walk test at enrollment. Correlations were analyzed using Pearson's correlation. Competing risk regression analysis was used to assess the predictive ability of the liver- and functional physiological reserve-related variables for ACLF.

Results

A total of 132 patients, predominantly with decompensated cirrhosis (87%), were included. Our study revealed a high prevalence of malnutrition (61%), sarcopenia (61%), visceral obesity (20%), sarcopenic visceral obesity (17%), and frailty (10%) among participants. Correlations between the assessment tools for sarcopenia and frailty were poor. Sarcopenia by SMI remained prevalent when frailty assessments were not usable. After a median follow-up of 10 months, 39% of the patients developed ACLF on WL, while 28% experienced dropouts without ACLF. Multivariate analysis identified MELD-Na, SMI, and LFI as independent predictors of ACLF on the WL. The predictive model MELD-Na-sarcopenia-LFI had a C-statistic of 0.85.

Conclusions

The poor correlation between sarcopenia assessment tools and frailty underscores the importance of a comprehensive evaluation. The SMI, LFI, and MELD-Na independently predicted ACLF development in WL. These findings enhance our understanding of the relationship between sarcopenia, frailty, and ACLF in patients awaiting LT, emphasizing the need for early detection and intervention to improve WL outcomes.

Impact and implications

The relationship between sarcopenia and frailty assessment tools, as well as their ability to predict acute-on-chronic liver failure (ACLF) in patients on the liver transplant (LT) waiting list (WL), remains poorly understood. Existing objective frailty screening tests have limitations when applied to critically ill patients. The correlation between sarcopenia and frailty assessment tools was weak, suggesting that they may capture different phenotypes. Sarcopenia assessed by skeletal muscle index, frailty evaluated using the liver frailty index, and the model for end-stage liver disease-Na score independently predicted the development of ACLF in patients on the WL. Our findings support the integration of liver frailty index and skeletal muscle index assessments at the time of inclusion on the WL for LT. This combined approach allows for the identification of a specific patient subgroup with an increased susceptibility to ACLF, underscoring the importance of early implementation of targeted treatment strategies to improve outcomes for patients awaiting LT.

Novel Therapeutic Approaches in Treatment of Acute-on-Chronic Liver Failure

Acute-on-chronic liver failure (ACLF), a clinical syndrome that can develop at any stage in the progression of cirrhotic liver disease, is characterized by an acute decompensation in liver function with associated multiorgan failure and high short-term mortality. Current evidence points to ACLF being reversible, particularly in those at the lower end of the severity spectrum. However, there are no specific treatments for ACLF, and overall outcomes remain poor. Expedited liver transplantation as a treatment option is limited by organ shortage and a lack of priority allocation for this indication. Other options are therefore urgently needed, and our improved understanding of the condition has led to significant efforts to develop novel therapies. In conclusion, this review aims to summarize the current understanding of the pathophysiological processes involved in the onset, progression, and recovery of ACLF and discuss novel therapies under development.

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.

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.

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.

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.

Liver Transplantation in Patients with Acute-onChronic Liver Failure: Challenging the Limits

Acute-on-chronic liver failure (ACLF) is one of the main causes of death on the waiting list. Liver transplantation (LT) is the only curative treatment for patients with ACLF and therefore it should be considered in all cases. However, the applicability of LT in patients with ACLF is challenging, given the scarcity of donors and the high short-term mortality of these patients. Organ allocation has traditionally been prioritised according to the model for end-stage liver disease (MELD) system. However, the accuracy of MELD score is limited in patients with ACLF. In this article, the authors review the outcomes of patients with ACLF before and after LT, highlighting its clinical course, the feasibility of LT in the sickest patients, the role of the organ allocation system, and possible indicators of futility.

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.

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.

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.