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

Reduced short-term survival following liver transplant in patients with acute-on-chronic liver failure: Reevaluating OPTN data

BACKGROUND

Prior studies show severe acute-on-chronic liver failure (ACLF) at liver transplantation (LT) negatively impacts short-term, but not long-term, post-LT outcomes. However, not accounting for ACLF's time-varying effect on the waitlist may underappreciate its dynamic nature. Moreover, excluding those who died or dropped off the waitlist raises concerns about selection bias.

METHODS

This US nationwide retrospective cohort study estimated the effect of severe ACLF (grade 3) (ACLF-3) on post-LT outcomes, including adult, first-time deceased donor LT candidates listed from June 2013 to May 2023. A marginal structural model (MSM) to address selection bias and time-varying exposure (ACLF-3) was applied, with extended Cox proportional hazard models using a Heaviside step function to assess the hazard of death after LT.

RESULTS

Among 31,267 eligible candidates for LT (baseline cohort), 11.3% (n = 3518) had ACLF-3 at listing; 13.6% (n = 4243) died or dropped out while on the LT waitlist. Of the 27,024 patients who received LT (transplanted cohort), 12.3% (n = 3333) had ACLF-3 at LT. ACLF-3 at LT (but not at waitlisting) was associated with a higher hazard of death, with the hazard ratio of 1.80 (95% CI: 1.09-2.97) within 1 year after LT but not thereafter. This marginal structural model effect size was 9% higher than conventional multivariable Cox proportional hazard models. Sensitivity analyses corroborated these findings.

CONCLUSIONS

Compared to previous studies, ACLF-3 at LT in our marginal structural model was associated with a discernible increase in short-term mortality after transplant, presumably due to our addressing of selection bias, while long-term survival was similar to those without severe ACLF at LT. However, potential vulnerability to posttransplant complications warrants further investigation.

Improvement in Survival After Transplantation for Critically Ill Patients With Cirrhosis in the United States

INTRODUCTION

There is considerable debate over the indication of liver transplantation (LT) for critically ill patients with cirrhosis, in part due to their potentially poor post-LT prognosis. We analyzed the epidemiology and outcome of LT for critically ill patients with cirrhosis over 4 time periods of 4 years.

METHODS

We included adult patients who underwent liver transplant alone between 2005 and 2020 using the United Network for Organ Sharing registry database. We defined critically ill patients with cirrhosis as being in the intensive care unit with 1 or more of the following characteristics at the time of LT: (i) grade III/IV hepatic encephalopathy, (ii) mechanical ventilation, (iii) dialysis, and (iv) vasopressors.

RESULTS

A total of 85,594 LT recipients were included, 5,827 (6.8%) of whom were classified as being critically ill with cirrhosis at the time of LT. The number and percentage of critically ill LT recipients with cirrhosis increased over the study period: 819 (4.3%) in 2005-2008 vs 2,067 (7.9%) in 2017-2020, P < 0.001. There was a 17% absolute increase in 1-year survival after LT: 72.5% in 2005-2008 vs 89.5% in 2017-2020, P < 0.001. The 1-year post-LT survival gap between critically ill and noncritically ill patients with cirrhosis narrowed over the study period: 16.7 percentage points in 2005-2008 vs 4.6 percentage points in 2017-2020. The year of LT was independently associated with lower 1-year post-LT mortality (hazard ratio 0.92, 95% confidence interval 0.91-0.93, P < 0.001).

DISCUSSION

The absolute number and relative percentage of LT recipients who were critically ill increased over time, as did 1-year post-LT survival. Meanwhile, the gap in survival between this group of patients and noncritically ill patients with cirrhosis decreased but persisted. Cautious access to selected LT candidates who are critically ill may be warranted, provided the gap in survival with noncritically ill patients remains as small as possible.

Liver diseases: epidemiology, causes, trends and predictions

As a highly complex organ with digestive, endocrine, and immune-regulatory functions, the liver is pivotal in maintaining physiological homeostasis through its roles in metabolism, detoxification, and immune response. Various factors including viruses, alcohol, metabolites, toxins, and other pathogenic agents can compromise liver function, leading to acute or chronic injury that may progress to end-stage liver diseases. While sharing common features, liver diseases exhibit distinct pathophysiological, clinical, and therapeutic profiles. Currently, liver diseases contribute to approximately 2 million deaths globally each year, imposing significant economic and social burdens worldwide. However, there is no cure for many kinds of liver diseases, partly due to a lack of thorough understanding of the development of these liver diseases. Therefore, this review provides a comprehensive examination of the epidemiology and characteristics of liver diseases, covering a spectrum from acute and chronic conditions to end-stage manifestations. We also highlight the multifaceted mechanisms underlying the initiation and progression of liver diseases, spanning molecular and cellular levels to organ networks. Additionally, this review offers updates on innovative diagnostic techniques, current treatments, and potential therapeutic targets presently under clinical evaluation. Recent advances in understanding the pathogenesis of liver diseases hold critical implications and translational value for the development of novel therapeutic strategies.

Robust Predictive Performance of the SALT-M Score for Clinical Outcomes in Asian Patients With Acute-on-Chronic Liver Failure

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a syndrome of patients with chronic liver disease presenting with multiple organ failures. Recently, Sundaram-ACLF-LT Mortality (SALT-M) score has been developed to predict 1-year post-liver transplantation mortality. We validated the SALT-M score in a large-volume, Asian single-centre cohort.

AIMS

We validated the SALT-M score in a large-volume, Asian single-centre cohort.

METHODS

We analysed 224 patients of ACLF grade 2-3. Area under the receiver operating characteristic curve (AUROC) and concordance index (c-index) were used to assess and compare the predictability of posttransplant mortality of SALT-M and other scores. Moreover, we compared the survivals of patients with high and low SALT-M, in conjunction with MELD score and ACLF grade.

RESULTS

The AUROC for prediction of 1-year post-LT survival was higher in SALT-M (0.691) than in MELD, MELD-Na, MELD 3.0 and delta-MELD. Similarly, the c-index of the SALT-M (0.650) was higher than aforementioned MELD systems. When categorised by the cut-off of SALT-M ≥ 20 and MELD ≥ 30, patients with high SALT-M exhibited lower post-LT survival than those with low SALT-M scores regardless of high or low MELD (40.0% for high SALT-M/high MELD vs. 42.9% for high SALT-M/low MELD vs. 73.8% for low SALT-M/high MELD vs. 63.7% for low SALT-M/low MELD, p < 0.001). In patients with ACLF grade 3, SALT-M effectively stratified the posttransplant mortality (39.4% for high SALT-M vs. 63.1% for low SALT-M, p = 0.018).

CONCLUSIONS

SALT-M outperformed previous MELD systems for predicting posttransplant mortality in Asian LT cohort with severe ACLF. Transplantability for patients with severe ACLF could be determined based on SALT-M.

Long-term outcome following liver transplantation of patients with ACLF grade 3

BACKGROUND & AIMS

Utility, a major principle for allocation in the context of transplantation, is questioned in patients with acute-on-chronic liver failure grade 3 (ACLF-3) who undergo liver transplantation (LT). We aimed to explore long-term outcomes of patients included in a three-centre retrospective French study published in 2017.

METHOD

All patients with ACLF-3 (n = 73), as well as their transplanted matched controls with ACLF-2 (n = 145), 1 (n = 119) and no ACLF (n = 292), who participated in the Princeps study published in 2017 were included. We explored 5- and 10-year patient and graft survival rates, causes of death and their predictive factors.

RESULTS

Median follow-up of patients with ACLF-3 was 7.5 years. At LT, median MELD was 40. In patients with ACLF-3, 2, 1 and no ACLF, 5-year patient survival rates were 72.6% vs. 69.7% vs. 76.4% vs. 77.0%, respectively (p = 0.31). Ten-year patient survival for ACLF-3 was 56.8% and was not different to other groups (p = 0.37). Leading causes of death in patients with ACLF-3 were infections (33.3%) and cardiovascular events (23.3%). After exclusion of early death, UCLA futility risk score, age-adjusted Charlson comorbidity index and CLIF-C ACLF score were independently associated with 10-year patient survival. Long-term graft survival rates were not different across the groups. Clinical frailty scale and WHO performance status improved over time in patients alive after 5 years.

CONCLUSION

5- and 10-year patient and graft survival rates were not different in patients with ACLF-3 compared to matched controls. 5-year patient survival is higher than the 50%-70% threshold defining the utility of a liver graft. Efforts should focus on candidate selection based on comorbidities, as well as the prevention of infection and cardiovascular events.

IMPACT AND IMPLICATIONS

While short-term outcomes following liver transplantation in the most severely ill patients with cirrhosis (acute-on-chronic liver failure grade 3 [ACLF-3]) are known, long-term data are limited, raising questions about the utility of graft allocation in the context of scarce medical resources. This study provides a favourable long-term update, confirming no differences in 5- and 10-year patient and graft survival following liver transplantation in patients with ACLF-3 compared to matched patients with ACLF-2, ACLF-1, and no-ACLF. The study highlights the risk of dying from infection and cardiovascular causes in the long-term and identifies scores including comorbidity evaluation, such as the age-adjusted Charlson comorbidity index, as independently associated with long-term survival. Therefore, physicians should consider the cumulative burden of comorbidities when deciding whether to transplant these patients. Additionally, after transplantation, the study encourages mitigating infectious risk with tailored immunosuppressive regimens and tightly managing cardiovascular risk over time.

Liver transplantation for critically ill patients with acute on chronic liver failure: a prospective national programme of waitlist prioritisation

Background

Acute on Chronic Liver Failure (ACLF) complicates chronic liver disease (CLD) combining rapidly progressive hepatic with extra-hepatic multiple organ failure and high short-term mortality. Effective therapeutic options are very limited, and liver transplantation (LT) seldom utilised through concerns of high recipient mortality and resource use. Retrospective reports suggest recent outcomes may have improved, but use of LT for ACLF has not been prospectively assessed.

Methods

A prospective programme of prioritised liver graft allocation for selected recipients with ACLF through registration on a new national tier, initiated in May 2021 in all 7 United Kingdom LT centres. Candidates were selected by centre multidisciplinary teams, with inclusion criteria mandating cirrhotic CLD with ACLF requiring critical care (CC) organ support and expected 1-month mortality >50%. Exclusion criteria included age ≥60 years, previous LT, comorbidity or substance misuse profile precluding elective LT. A pilot 50 registrations were planned, with pre-specified futility criteria of a 1-year post-LT survival of 60%.

Findings

Fifty-two patients were registered on the ACLF tier, median (IQR) age 46 (39-52) years, ACLF grade 3 (3-3) and Model for End-stage Liver Disease (MELD) 39 (35-40). At registration 32 (62%) required mechanical ventilation, 44 (85%) vasopressors and 46 (89%) renal replacement. Forty-two (81%) underwent LT 2 (2-5) days after registration: 10 (19%) did not. All non-transplanted died at median 7 (4-13) days after registration (p < 0.0001 vs. LT). Post-LT follow-up was 212 (119-530) days and patient survival 81% (95% CI 66-91): 28-, 90-day and 1-year survival after registration 93%, 86% and 77%. Median length of CC and hospital stay in LT recipients was 16 (8-28) and 35 (23-54) days respectively.

Interpretation

We report the first prospective national series of prioritised liver transplantation for critically ill patients with ACLF. For selected recipients LT is a practical and highly effective treatment option where no other similarly effective interventions exist.

Funding

There was no funding for the study.

Managing Multiorgan Failure in Acute on Chronic Liver Failure

Acute-on-chronic liver failure (ACLF) is defined as a clinical syndrome that develops in patients with chronic liver disease characterized by the presence of organ failure and high short-term mortality, although there is still no worldwide consensus on diagnostic criteria. Management of ACLF is mainly based on treatment of "precipitating factors" (the most common are infections, alcohol-associated hepatitis, hepatitis B flare, and bleeding) and support of organ failure, which often requires admission to the intensive care unit. Liver transplantation should be considered in patients with ACLF grades 2 to 3 as a potentially life-saving treatment. When a transplant is not indicated, palliative care should be considered after 3 to 7 days of full organ support in patients with at least four organ failures or a CLIF-C ACLF score of >70. This review summarizes the current knowledge on the management of organ failure in patients with ACLF, focusing on recent advances.

Common definitions and variables are needed for the United States to join the conversation on acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is a variably defined syndrome characterized by acute decompensation of cirrhosis with organ failures. At least 13 different definitions and diagnostic criteria for ACLF have been proposed, and there is increasing recognition that patients with ACLF may face disadvantages in the current United States liver allocation system. There is a need, therefore, for more standardized data collection and consensus to improve study design and outcome assessment in ACLF. In this article, we discuss the current landscape of transplantation for patients with ACLF, strategies to optimize organ utility, and data opportunities based on emerging technologies to facilitate improved data collection.

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.

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.

Intensive care management of acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is a clinical syndrome defined by an acute deterioration of the liver function associated with extrahepatic organ failures requiring intensive care support and associated with a high short-term mortality. ACLF has emerged as a major cause of mortality in patients with cirrhosis and chronic liver disease. ACLF has a unique pathophysiology in which systemic inflammation plays a key role; this provides the basis of novel therapies, several of which are now in clinical trials. Intensive care unit (ICU) therapy parallels that applied in the general ICU population in some organ failures but has peculiar differential characteristics in others. Critical care management strategies and the option of liver transplantation (LT) should be balanced with futility considerations in those with a poor prognosis. Nowadays, LT is the only life-saving treatment that can radically improve the long-term prognosis of patients with ACLF. This narrative review will provide insights on the current understanding of ACLF with emphasis on intensive care management.