Acute on Chronic Liver Failure From Nonalcoholic Fatty Liver Disease: A Growing and Aging Cohort With Rising Mortality

Plasticity, heterogeneity, and multifunctionality of hepatic stellate cells in liver pathophysiology

HSCs, the resident pericytes of the liver, have consistently been at the forefront of liver research due to their crucial roles in various hepatic pathological processes. Prior literature often depicted HSCs in a binary framework, categorizing them as either quiescent or activated. However, recent advances in HSC research, particularly the advent of single-cell RNA-sequencing, have revolutionized our understanding of these cells. This sophisticated technique offers an unparalleled, high-resolution insight into HSC populations, uncovering a spectrum of diversity and functional heterogeneity across various physiological states of the liver, ranging from liver development to the liver aging process. The single-cell RNA-sequencing revelations have also highlighted the intrinsic plasticity of HSCs and underscored their complex roles in a myriad of pathophysiological processes, including liver injury, repair, and carcinogenesis. This review aims to integrate and clarify these recent discoveries, focusing on how the inherent plasticity of HSCs is central to their dynamic roles both in maintaining liver homeostasis and orchestrating responses to liver injury. Future research will clarify whether findings from rodent models can be translated to human livers and guide how these insights are harnessed to develop targeted therapeutic interventions.

Prevention in Hepatology

The prevention of liver disease has improved significantly in the last few decades, to the point that it can now be considered a true success story. The wide variety of interventions, including comprehensive vaccination strategies, novel medications, lifestyle changes, and even preventive surgeries, have reduced the morbidity and mortality of chronic liver diseases. However, the prevalence of chronic liver diseases is increasing worldwide. Currently, fatty liver disease alone is estimated to be present in as much as 30% of the adult population. Furthermore, there is a trend towards increasing incidences of chronic hepatitis B, and a global lack of success in efforts to eliminate chronic hepatitis C. Thus, improving and efficiently rolling out existing and successful prevention strategies for chronic liver diseases will play an essential role in healthcare throughout the upcoming decades. In this review, we summarize the current options and concepts for preventing chronic liver diseases, highlight their limitations, and provide an outlook on probable future developments to improve awareness, integrated care, and the analysis of big data.

Mechanism and Effect of HNF4α Decrease in a Rat Model of Cirrhosis and Liver Failure

BACKGROUND & AIMS

HNF4α, a master regulator of liver development and the mature hepatocyte phenotype, is down-regulated in chronic and inflammatory liver disease. We used contemporary transcriptomics and epigenomics to study the cause and effects of this down-regulation and characterized a multicellular etiology.

METHODS

Progressive changes in the rat carbon tetrachloride model were studied by deep RNA sequencing and genome-wide chromatin immunoprecipitation sequencing analysis of transcription factor (TF) binding and chromatin modification. Studies compared decompensated cirrhosis with liver failure after 26 weeks of treatment with earlier compensated cirrhosis and with additional rat models of chronic fibrosis. Finally, to resolve cell-specific responses and intercellular signaling, we compared transcriptomes of liver, nonparenchymal, and inflammatory cells.

RESULTS

HNF4α was significantly lower in 26-week cirrhosis, part of a general reduction of TFs that regulate metabolism. Nevertheless, increased binding of HNF4α contributed to strong activation of major phenotypic genes, whereas reduced binding to other genes had a moderate phenotypic effect. Decreased Hnf4a expression was the combined effect of STAT3 and nuclear factor kappa B (NFκB) activation, which similarly reduced expression of other metabolic TFs. STAT/NFκB also induced de novo expression of Osmr by hepatocytes to complement induced expression of Osm by nonparenchymal cells.

CONCLUSIONS

Liver decompensation by inflammatory STAT3 and NFκB signaling was not a direct consequence of progressive cirrhosis. Despite significant reduction of Hnf4a expression, residual levels of this abundant TF still stimulated strong new gene expression. Reduction of HNF4α was part of a broad hepatocyte transcriptional response to inflammation.

NIS2+™, an effective blood-based test for the diagnosis of at-risk nonalcoholic steatohepatitis in adults 65 years and older

BACKGROUND

Older patients are at increased risk for at-risk NASH, defined as NASH with NAFLD activity scores (NAS) ≥4 and significant fibrosis (F ≥ 2). The aim of this study was to compare the performance of 2 new blood tests, NIS4® and NIS2+™, with FIB-4, NFS, ELF™, and alanine aminotransferase (ALT) for the diagnosis of at-risk NASH in a cohort of patients aged ≥65 years.

METHODS

The clinical performance of multiple blood-based tests was assessed for their ability to detect at-risk NASH using the RESOLVE-IT diag cohort, a large population of patients with metabolic risk who were screened for potential inclusion in the RESOLVE-IT phase 3 trial.

RESULTS

The study cohort (n = 2053) included patients with the full histological spectrum of NAFLD, with patients having liver fibrosis stages F0-4 and NAS scores 0-8. NIS4® and NIS2+™ showed similar assay performance in patients who were <65 versus ≥65 years of age (AUROC = 0.80 vs. 0.78, p = 0.47; 0.81 vs. 0.83 p = 0.45, respectively) for the identification of at-risk NASH. In patients ≥65 (n = 410), NIS2+™ exhibited the highest AUROC compared to NIS4®, FIB-4, NFS, ELF™, and ALT (AUROC = 0.83 vs. 0.78, 0.68, 0.58, 0.69, 0.74, respectively; all p ≤ 0.0009). For NIS2+™, the sensitivity and NPV for ruling-out at-risk NASH at the 0.46 cutoff were 90.2% and 86.0%, and the specificity and PPV for ruling-in at-risk NASH at the 0.68 cutoff were81.1% and 76.3%, respectively.

CONCLUSIONS

The clinical performance of NIS2+™ was superior for the diagnosis of at-risk NASH in patients ≥65 years of age. These data support the clinical value of this blood-based test for the diagnosis of at-risk NASH in older adults.

Definition, diagnosis and epidemiology of acute-on-chronic liver failure

This narrative review addresses the definition of acute-on-chronic liver failure, a condition associated with high short-term mortality in patients with chronic liver disease and/or cirrhosis. We provide two major points of view: the East and the West perspective. Both definitions vary regarding the underlying patient population and organ failure(s) definition. Nevertheless, all the definitions have their clinical utility: from the core concept of having the "liver" as a conditio sine qua non, the syndrome cannot exist (Asian Pacific Association for the Study of the Liver); a data-driven, robust definition (European Association for the Study of the Liver); a bedside tool that can quickly identify patients at high risk of dying (North American Consortium for the Study of End-stage Liver Disease [NACSELD]). In each section, we provide the overall definitions, the criteria of organ failure(s), and some epidemiological data illustrating how these apply in each area of the world.

The NLRP3 inflammasome: contributions to inflammation-related diseases

The NOD-like receptor protein 3 (NLRP3) inflammasome is a protein complex that regulates innate immune responses by activating caspase-1 and the inflammatory cytokines interleukin (IL)-1β and IL-18. Multiple studies have demonstrated the importance of the NLRP3 inflammasome in the development of immune and inflammation-related diseases, including arthritis, Alzheimer's disease, inflammatory bowel disease, and other autoimmune and autoinflammatory diseases. This review first explains the activation and regulatory mechanism of the NLRP3 inflammasome. Secondly, we focus on the role of the NLRP3 inflammasome in various inflammation-related diseases. Finally, we look forward to new methods for targeting the NLRP3 inflammasome to treat inflammation-related diseases, and provide new ideas for clinical treatment.

Patients With Acute-on-Chronic Liver Failure Have Greater Healthcare Resource Utilization After Liver Transplantation

BACKGROUND & AIMS

Although liver transplantation (LT) has been demonstrated to provide survival benefit for patients with acute-on-chronic liver failure (ACLF), data are lacking regarding resource utilization for this population after LT.

METHODS

We retrospectively reviewed data from 10 centers in North America of patients transplanted between 2018 and 2019. ACLF was identified by using the European Association for the Study of the Liver-Chronic Liver Failure criteria.

RESULTS

We studied 318 patients of whom 106 patients (33.3%) had no ACLF, 61 (19.1%) had ACLF-1, 74 (23.2%) had ACLF-2, and 77 (24.2%) had ACLF-3 at transplantation. Healthcare resource utilization after LT was greater among recipients with ACLF compared with patients without ACLF regarding median post-LT length of hospital stay (LOS) (P < .001), length of post-LT dialysis (P < .001), discharge to a rehabilitation center (P < .001), and 30-day readmission rates (P = .042). Multivariable negative binomial regression analysis demonstrated a significantly longer LOS for patients with ACLF-1 (1.9 days; 95% confidence interval [CI], 0.82-7.51), ACLF-2 (6.7 days; 95% CI, 2.5-24.3), and ACLF-3 (19.3 days; 95% CI, 1.2-39.7), compared with recipients without ACLF. Presence of ACLF-3 at LT was also associated with longer length of dialysis after LT (9.7 days; 95% CI, 4.6-48.8) relative to lower grades. Multivariable logistic regression analysis revealed greater likelihood of discharge to a rehabilitation center among recipients with ACLF-1 (odds ratio [OR], 1.79; 95% CI, 1.09-4.54), ACLF-2 (OR, 2.23; 95% CI, 1.12-5.01), and ACLF-3 (OR, 2.23; 95% CI, 1.40-5.73). Development of bacterial infection after LT also predicted LOS (20.9 days; 95% CI, 6.1-38.5) and 30-day readmissions (OR, 1.39; 95% CI, 1.17-2.25).

CONCLUSIONS

Patients with ACLF at LT, particularly ACLF-3, have greater post-transplant healthcare resource utilization.

Influence of non-alcoholic fatty liver disease on non-variceal upper gastrointestinal bleeding: A nationwide analysis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the leading cause of liver disease globally with an estimated prevalence of 25%, with the clinical and economic burden expected to continue to increase. In the United States, non-variceal upper gastrointestinal bleeding (NVUGIB) has an estimated incidence of 61-78 cases per 100000 people with a mortality rate of 2%-15% based on co-morbidity burden.

AIM

To identify the outcomes of NVUGIB in NAFLD hospitalizations in the United States.

METHODS

We utilized the National Inpatient Sample from 2016-2019 to identify all NVUGIB hospitalizations in the United States. This population was divided based on the presence and absence of NAFLD. Hospitalization characteristics, outcomes and complications were compared.

RESULTS

The total number of hospitalizations for NVUGIB was 799785, of which 6% were found to have NAFLD. NAFLD and GIB was, on average, more common in younger patients, females, and Hispanics than GIB without NAFLD. Interestingly, GIB was less common amongst blacks with NAFLD. Multivariate logistic regression analysis was conducted, controlling for the multiple covariates. The primary outcome of interest, mortality, was found to be significantly higher in patients with NAFLD and GIB [adjusted odds ratio (aOR) = 1.018 (1.013-1.022)]. Secondary outcomes of interest, shock [aOR = 1.015 (1.008-1.022)], acute respiratory failure [aOR = 1.01 (1.005-1.015)] and acute liver failure [aOR = 1.016 (1.013-1.019)] were all more likely to occur in this cohort. Patients with NAFLD were also more likely to incur higher total hospital charges (THC) [$2148 ($1677-$2618)]; however, were less likely to have a longer length of stay [0.27 d (0.17-0.38)]. Interestingly, in our study, the patients with NAFLD were less likely to suffer from acute myocardial infarction [aOR = 0.992 (0.989-0.995)]. Patients with NAFLD were not more likely to suffer acute kidney injury, sepsis, blood transfusion, intubation, or dialysis.

CONCLUSION

NVUGIB in NAFLD hospitalizations had higher inpatient mortality, THC, and complications such as shock, acute respiratory failure, and acute liver failure compared to those without NAFLD.

Current therapeutic modalities and chemopreventive role of natural products in liver cancer: Progress and promise

Liver cancer is a severe concern for public health officials since the clinical cases are increasing each year, with an estimated 5-year survival rate of 30%–35% after diagnosis. Hepatocellular carcinoma (HCC) constitutes a significant subtype of liver cancer (approximate75%) and is considered primary liver cancer. Treatment for liver cancer mainly depends on the stage of its progression, where surgery including, hepatectomy and liver transplantation, and ablation and radiotherapy are the prime choice. For advanced liver cancer, various drugs and immunotherapy are used as first-line treatment, whereas second-line treatment includes chemotherapeutic drugs from natural and synthetic origins. Sorafenib and lenvatinib are first-line therapies, while regorafenib and ramucirumab are second-line therapy. Various metabolic and signaling pathways such as Notch, JAK/ STAT, Hippo, TGF-β, and Wnt have played a critical role during HCC progression. Dysbiosis has also been implicated in liver cancer. Drug-induced toxicity is a key obstacle in the treatment of liver cancer, necessitating the development of effective and safe medications, with natural compounds such as resveratrol, curcumin, diallyl sulfide, and others emerging as promising anticancer agents. This review highlights the current status of liver cancer research, signaling pathways, therapeutic targets, current treatment strategies and the chemopreventive role of various natural products in managing liver cancer.

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.

High frequency of acute decompensation and cancer in patients with compensated cirrhosis due to nonalcoholic fatty liver disease: A retrospective cohort study

The natural history of compensated cirrhosis due to nonalcoholic fatty liver disease (NAFLD) has not been completely characterized. The aim of the present study was to assess the incidence and risk factors of acute decompensation of cirrhosis, hepatocellular carcinoma, and extrahepatic cancers. This was a multicenter, retrospective, cohort study including 449 patients with compensated cirrhosis due to NAFLD. We calculated cumulative incidences and used competitive risk analysis to determine the risk factors associated with decompensation and cancer development. Over a median of 39 months of follow-up, 124 patients (28%) presented acute decompensation. The most frequent decompensation was ascites (21%) followed by hepatic encephalopathy (15%), variceal bleeding (9%), and spontaneous bacterial peritonitis (3%). Acute-on-chronic liver failure was diagnosed in 6% of patients during follow-up. Liver function parameters and specifically an albumin level below 40 g/L were independently associated with an increased risk of decompensation. The presence of ischemic heart disease was independently associated with acute decompensation. Seventy-eight patients (18%) developed hepatocellular carcinoma or extrahepatic cancers during follow-up (51 and 27, respectively). Conclusion: Patients with compensated cirrhosis due to NAFLD are at high risk of severe liver complications, such as the development of acute decompensation, in a relative short follow-up time. This population is at high risk of hepatic and extrahepatic cancers.

Rising Trend in Waitlisting for Alcoholic Hepatitis With More Favorable Outcomes Than Other High Model for End-stage Liver Disease in the Current Era

BACKGROUND

In the appropriate candidate, liver transplantation (LT) is a viable treatment for alcoholic hepatitis (AH). We compared the waitlisting trends and outcomes of AH patients in the context of others with high Model for End-stage Liver Disease (MELD) score.

METHODS

LT listings for AH between January 1, 2008, and June 12, 2020 were identified in the United Network for Organ Sharing database. Temporal trends in listings for AH were assessed. Covariate adjusted competing risks models evaluated waitlist mortality and LT rates between AH candidates and others with listing native MELD ≥30.

RESULTS

Between 2008 and 2019, waitlist additions for AH increased 6.5-fold. Waiting time for AH candidates was short (median 10 d). Delisting for clinical improvement was infrequent in AH, albeit higher than MELD ≥30 patients (3.3% versus 0.8%; P < 0.001). Among 99 centers with ≥1 AH listing, AH patients accounted for 0.2%-18.2% of all alcohol-related listings and 0.6%-25.0% of those with native listing MELD ≥30. Overall listing volume was larger at these 99 centers than the 40 with no AH listings (P < 0.001). AH candidates in 2014-2020 experienced improved waitlist survival (adjusted subhazard ratio, 0.67; 95% confidence interval, 0.52-0.86; P = 0.002) and higher transplant rates (adjusted subhazard ratio, 1.14; 95% confidence interval, 1.04-1.25; P = 0.006) versus other MELD ≥30 candidates.

CONCLUSIONS

There has been a rising trend in waitlisting patients with AH and high MELD score. Liver disease causes influence waitlist outcomes and those of AH candidates are more favorable. Further research and allocation adjustments may be needed to ensure equitable organ allocation, based on liver disease cause, for those on the LT waitlist.

Risk Factors for Posttransplantation Mortality in Recipients With Grade 3 Acute-on-Chronic Liver Failure: Analysis of a North American Consortium

Although liver transplantation (LT) yields survival benefit for patients with acute-on-chronic liver failure grade 3 (ACLF-3), knowledge gaps remain regarding risk factors for post-LT mortality. We retrospectively reviewed data from 10 centers in the United States and Canada for patients transplanted between 2018 and 2019 and who required care in the intensive care unit prior to LT. ACLF was identified using the European Association for the Study of the Liver-Chronic Liver Failure (EASL-CLIF) criteria. A total of 318 patients were studied, of whom 106 (33.3%) had no ACLF, 61 (19.1%) had ACLF-1, 74 (23.2%) had ACLF-2, and 77 (24.2%) had ACLF-3 at transplantation. Survival probability 1 year after LT was significantly higher in patients without ACLF (94.3%) compared with patients with ACLF (87.3%; P = 0.02), but similar between ACLF-1 (88.5%), ACLF-2 (87.8%), and ACLF-3 (85.7%; P = 0.26). Recipients with ACLF-3 and circulatory failure (n = 29) had similar 1-year post-LT survival (82.3%) compared with patients with ACLF-3 without circulatory failure (89.6%; P = 0.32), including those requiring multiple vasopressors. For patients transplanted with ACLF-3 including respiratory failure (n = 20), there was a trend toward significantly lower post-LT survival (P =  0.07) among those with respiratory failure (74.1%) compared with those without (91.0%). The presence of portal vein thrombosis (PVT) at LT for patients with ACLF-3 (n = 15), however, yielded significantly lower survival (91.9% versus 57.1%; P < 0.001). Multivariable logistic regression analysis revealed that PVT was significantly associated with post-LT mortality within 1 year (odds ratio, 7.3; 95% confidence interval, 1.9-28.3). No correlation was found between survival after LT and the location or extent of PVT, presence of transjugular intrahepatic portosystemic shunt, or anticoagulation. LT in patients with ACLF-3 requiring vasopressors yields excellent 1-year survival. LT should be approached cautiously among candidates with ACLF-3 and PVT.

Metabolic Risk Factors Are Associated with the Disease Severity and Prognosis of Hepatitis B Virus-Related Acute on Chronic Liver Failure

Background/Aims

Metabolic risk factors could accelerate hepatitis B virus (HBV)-related mortality; however, their impacts on disease severity in HBV-related acute on chronic liver failure (HBV-ACLF) patients remain unexplored. In this study, we assessed the effects of metabolic risk factors on the outcome of HBV-ACLF patients.

Methods

This study retrospectively enrolled antiviral therapy naïve HBV-ACLF patients from a single center in China. Patients were evaluated according to Child-Turcotte-Pugh score, Model for End-Stage Liver Disease (MELD) score, 30-day, 90-day mortality and survival rate to estimate the prognosis of HBV-ACLF. The impacts of different metabolic risk factors were further analyzed.

Results

A total of 233 patients, including 158 (67.8%) with metabolic risk factors and 75 (32.2%) without metabolic risk factors, were finally analyzed. Patients with metabolic risk factors had significantly higher MELD score (22.6±6.1 vs 19.8±3.8, p<0.001), 90-day mortality rate (56.3% vs 38.7%, p=0.017), and shorter median survival time (58 days vs 75 days hazard ratio, 1.553; 95% confidence interval, 1.061 to 2.274; p=0.036) than patients without them. Moreover, metabolic risk factors were independently associated with patients’ 90-day mortality (hazard ratio, 1.621; 95% confidence interval, 1.016 to 2.585; p=0.043). Prediabetes/diabetes and hypertension were related to higher rates of infection and worse renal function in HBV-ACLF patients.

Conclusions

HBV-ACLF patients with metabolic risk factors, especially prediabetes/diabetes or hypertension, could have more severe disease and lower survival rates. In addition, the existence of metabolic disorder is an independent risk factor for HBV-ACLF patients’ 90-day mortality.

The E3 ubiquitin-protein ligase Trim31 alleviates non-alcoholic fatty liver disease by targeting Rhbdf2 in mouse hepatocytes

Systemic metabolic syndrome significantly increases the risk of morbidity and mortality in patients with non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). However, no effective therapeutic strategies are available, practically because our understanding of its complicated pathogenesis is poor. Here we identify the tripartite motif-containing protein 31 (Trim31) as an endogenous inhibitor of rhomboid 5 homolog 2 (Rhbdf2), and we further determine that Trim31 directly binds to Rhbdf2 and facilitates its proteasomal degradation. Hepatocyte-specific Trim31 ablation facilitates NAFLD-associated phenotypes in mice. Inversely, transgenic or ex vivo gene therapy-mediated Trim31 gain-of-function in mice with NAFLD phenotypes virtually alleviates severe deterioration and progression of steatohepatitis. The current findings suggest that Trim31 is an endogenous inhibitor of Rhbdf2 and downstream cascades in the pathogenic process of steatohepatitis and that it may serve as a feasible therapeutical target for the treatment of NAFLD/NASH and associated metabolic disorders.

Nonalcoholic steatohepatitis (NASH) is a chronic liver disease with complex disease mechanisms. Here the authors report that the E3 ubiquitin-protein ligase Trim31 mitigates development of NASH via inhibition of rhomboid 5 homolog 2 (Rhbdf2) in mice.

Metabolic associated fatty liver disease and acute-on-chronic liver failure: common themes for common problems

Metabolic associated fatty liver disease (MAFLD) affects 20-30% of the worldwide population and is becoming the most common cause of chronic liver disease, cirrhosis and hepatocellular carcinoma (HCC). MAFLD is the hepatic expression of metabolic dysfunction correlated with a variety of metabolic comorbidities including obesity, dyslipidemia, hypertension and type 2 diabetes (T2DM). Obesity, altered gut permeability, chronic inflammation and dysbiosis related to MAFLD might predispose patients with cirrhosis to the development of acute-on-chronic liver failure (ACLF); however, this relationship remains unclear. ACLF is a syndrome with high short-term mortality, presenting with acute hepatic decompensation associated with organ failures in patients with underlying chronic liver disease with or without an identifiable precipitating event. While this syndrome can occur in any patient with cirrhosis, the increasing prevalence of cirrhosis due to MAFLD is of great concern because, in a recent analysis, MAFLD was the fastest rising cause of cirrhosis associated with ACLF among patients listed for LT in the US. In this review, we will discuss the current knowledge on MAFLD and the development of ACLF.

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.

Current State of Multiorgan Transplantation and Implications for Future Practice and Policy

The incidence of kidney dysfunction has increased in liver transplant and heart transplant candidates, reflecting a changing patient population and allocation policies that prioritize the most urgent candidates. A higher burden of pretransplant kidney dysfunction has resulted in a substantial rise in the utilization of multiorgan transplantation (MOT). Owing to a shortage of available deceased donor kidneys, the increased use of MOT has the potential to disadvantage kidney-alone transplant candidates, as current allocation policies generally provide priority for MOT candidates above all kidney-alone transplant candidates. In this review, the implications of kidney disease in liver transplant and heart transplant candidates is reviewed, and current policies used to allocate organs are discussed. Important ethical considerations pertaining to MOT allocation are examined, and future policy modifications that may improve both equity and utility in MOT policy are considered.

Primary biliary cholangitis has the highest waitlist mortality in patients with cirrhosis and acute on chronic liver failure awaiting liver transplant

BACKGROUND

Data are sparse on etiology specific outcomes on waitlist (WL) and post-transplant outcomes among patients with acute on chronic liver failure (ACLF).

METHODS AND RESULTS

In a retrospective cohort of 14,774 adults from United network for organ sharing (UNOS) database listed for Liver transplantation (LT) with cirrhosis and ACLF (January 2013-June 2019), 40% were due to alcohol-associated liver disease (ALD), followed by hepatitis C virus (HCV) at 20%, non-alcoholic steatohepatitis (19%), cryptogenic cirrhosis (7%), autoimmune hepatitis (5%), primary sclerosing cholangitis (PSC) at 3%, and 2% each for hepatitis B, primary biliary cholangitis (PBC), and metabolic etiology. Using competing risk analysis, cumulative risk of WL mortality was highest for PBC at 20.5% and lowest for PSC at 13.3%, P < .001. Compared with ALD as reference, WL mortality was higher for PBC (1.45 [1.16-1.82]), and similar for other etiologies, P < .001. Of this cohort, 9650 (65.3%) patients received LT, with 1-year. patient survival of 91.6% for PBC, worst for cryptogenic cirrhosis (89.5%) and best for PSC and ALD (93.4%), P < .001.

CONCLUSION

Among listed candidates with ACLF, those with PBC have highest WL mortality 1-year. post-transplant survival was excellent among recipients for PBC. If these findings are validated in prospective studies, liver disease etiology should be considered for LT selection among patients in ACLF.

Treatment of Severe Acute on Chronic Liver Failure: Management of Organ Failures, Investigational Therapeutics, and the Role of Liver Transplantation

Acute on chronic liver failure (ACLF) is a unique syndrome that afflicts patients with chronic liver disease and results in high short-term mortality, in the setting of organ system failures. Given this prognosis, there is an urgent need to understand risk factors for this condition, for appropriate medical management of organ failures, and for selection criteria for patients who may benefit from liver transplantation (LT). Although several definitions exist to identify ACLF, all of them are designed to identify patients with uniquely high mortality. Currently, management of severe ACLF relies on best supportive care for specific organ failures. Thromboelastography should guide the evaluation of coagulation pathways and hyperfibrinolysis in ACLF; prophylactic blood product transfusions and thrombopoetin agonists are not recommended. Combination therapy with terlipressin and albumin has been shown to be efficacious in the management of the hepatorenal syndrome but should be administered with caution in patients with ACLF-3. Recent data have characterized the role of beta-blockers and transjugular intrahepatic portosystemic shunt placement in the management of ACLF. Investigational therapies such as extracorporeal liver support and hepatocyte stem cell therapies have shown promise; larger scale studies may better define the subpopulations of patients with ACLF mostly likely to benefit from these evolving therapeutics. Regarding LT in ACLF, data suggest that even patients with 3 or more organ system failures may have a 1-year survival >80%. However, further efforts are needed to understand the predictors of post-LT survival to facilitate LT criteria for this condition.

Evolution of liver transplant organ allocation policy: Current limitations and future directions

Since the adoption of the model for end-stage liver disease (MELD) score for organ allocation in 2002, numerous changes to the system of liver allocation and distribution have been made with the goal of decreasing waitlist mortality and minimizing geographic variability in median MELD score at time of transplant without worsening post-transplant outcomes. These changes include the creation and adoption of the MELD-Na score for allocation, Regional Share 15, Regional Share for Status 1, Regional Share 35/National Share 15, and, most recently, the Acuity Circles Distribution Model. However, geographic differences in median MELD at time of transplant remain as well as limits to the MELD score for allocation, as etiology of liver disease and need for transplant changes. Acute-on-chronic liver failure (ACLF) is a subset of liver failure where prevalence is rising and has been shown to have an increased mortality rate and need for transplantation that is under-demonstrated by the MELD score. This underscores the limitations of the MELD score and raises the question of whether MELD is the most accurate, objective allocation system. Alternatives to the MELD score have been proposed and studied, however MELD score remains as the current system used for allocation. This review highlights policy changes since the adoption of the MELD score, addresses limitations of the MELD score, reviews proposed alternatives to MELD, and examines the specific implications of these changes and alternatives for ACLF.

Alcohol-associated liver disease in the United States is associated with severe forms of disease among young, females and Hispanics

BACKGROUND

Alcohol use and alcohol-associated liver disease (ALD) burden are increasing in young individuals.

AIM

To assess host factors associated with this burden.

METHODS

National Health and Nutrition Examination Survey (NHANES), National Inpatient Sample (NIS), and United Network for Organ Sharing (UNOS) databases (2006-2016) were used to identify individuals with harmful alcohol use, ALD-related admissions, and ALD-related LT listings respectively.

RESULTS

Of 15 981 subjects in NHANES database, weighted prevalence of harmful alcohol use was 17.7%, 29.3% in <35 years (G1) versus 16.9% in 35-64 years (G2) versus 5.1% in ≥65 years (G3). Alcohol use was about 11 and 4.7 folds higher in G1 and G2 versus G3, respectively. Male gender and Hispanic race associated with harmful alcohol use. Of 593 600 ALD admissions (5%, 77%, and 18% in G1-G3 respectively), acute on chronic liver failure (ACLF) occurred in 7.2%, (7.2 in G2 vs 6.7% in G1 and G3, P < 0.001). After controlling for other variables, ACLF development among ALD hospitalizations was higher by 14% and 10% in G1 and G2 versus G3, respectively. Female gender and Hispanic race were associated with increased ACLF risk by 8% and 17% respectively. Of 20,245 ALD LT listings (3.4%, 84.4%, and 12.2% in G1-G3 respectively), ACLF occurred in 28% candidates. Risk of severe (grade 2 or 3) ACLF was higher by about 1.7 fold in G1, 1.5 fold in females and 20% in Hispanics.

CONCLUSION

Young age, female gender, and Hispanic race are independently associated with ALD-related burden and ACLF in the United States. If these findings are validated in prospective studies, strategies will be needed to reduce alcohol use in high risk individuals to reduce burden from ALD.

The Relationship between Hepatic Myeloid-Derived Suppressor Cells and Clinicopathological Parameters in Patients with Chronic Liver Disease

Myeloid-derived suppressor cells (MDSCs) have attracted attention due to their important role in inflammation. Several studies have investigated the involvement of MDSCs in chronic liver disease. However, due to the difference of MDSC phenotypes, patient types, and sample sources among the studies, the results are inconsistent and controversial. We took advantage of a large well-defined cohort of 98 (24 patients with CHB, 18 with NAFLD, 13 with HCC, 16 with PBC, and 27 with AIH) patients with liver inflammation and 12 healthy controls to investigate the expression of MDSCs, and the relationships between the expression of hepatic MDSCs and the clinical characteristics were analyzed. We found that the expression of CD11b+CD33+ MDSCs is closely related to chronic liver disease and positively correlated with clinical parameters such as ALT, AST, and globulin. Ultimately, the present study suggests that hepatic CD11b+CD33+ MDSCs are increased in HCC and AIH and positively correlate with the liver stages of hepatitis activity and liver fibrosis stage.