Hemodynamic studies in acute-on-chronic liver failure

Definitions, Etiologies, and Outcomes of Acute on Chronic Liver Failure: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is a major public health concern. We aimed to assess the definitions, etiologic spectrum, organ failure (OF), and outcomes of ACLF globally.

METHODS

Three databases were searched for studies on ACLF from 1990 until September 2022. Information regarding definitions, acute precipitants, underlying chronic liver disease (CLD), OF, and mortality were extracted. Meta-analyses were performed for pooled prevalence rates (95% confidence interval [CI]) using random-effects model for each definition of ACLF.

RESULTS

Of the 11,451 studies identified, 114 articles (142 cohorts encompassing 210,239 patients) met the eligibility criteria. Most studies (53.2%) used the European Association for the Study of the Liver (EASL) definition, followed by Asia-Pacific Association for the Study of the Liver (APASL) (33.3%). Systemic infection was the major acute precipitant, and alcohol use was the major cause of CLD in EASL-defined studies, whereas alcohol was both the major acute precipitant and cause of CLD in APASL-defined studies. Liver failure was the major OF in APASL-based studies, whereas renal failure was predominant in EASL-based studies. Thirty-day mortality varied across definitions: APASL: 38.9%, 95% CI, 31.2%-46.9%; EASL: 47.9%, 95% CI, 42.2%-53.5%; and NACSELD: 52.2%, 95% CI, 51.9%-52.5%. Diagnostic overlap between definitions ranged from 7.7% to 80.2%. Meta-regression suggested that the World Health Organization region influenced 30-day mortality in studies using EASL definition.

CONCLUSIONS

Heterogeneity in the definition of ACLF proposed by different expert societies and regional preferences in its use result in differences in clinical phenotype and outcomes. A uniform definition would enhance the comparability and interpretation of global data.

Interleukin-8 predicts short-term mortality in acute-on-chronic liver failure patients with hepatitis B-related-related cirrhosis background

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a distinctive and severe syndrome, marked by an excessive systemic inflammatory response. In vivo, interleukin 8 (IL-8) is an essential pro-inflammatory cytokine. We aimed to investigate the value of serum IL-8 levels in predicting mortality in ACLF patients in the background of hepatitis B virus-related cirrhosis.

METHODS

In this study, we conducted a retrospective analysis of the clinical baseline characteristics of 276 patients with ACLF in the context of HBV-related cirrhosis. Logistic regression analysis was employed to identify independent risk factors for short-, intermediate-, and long-term mortality. Using these independent risk factors, we developed a nomogram model, which was subsequently validated. To assess the clinical usefulness of the nomogram model, we performed decision curve analysis (DCA).

RESULTS

Out of the 276 patients with ACLF, 98 (35.5%), 113 (40.9%), and 128 (46.4%) died within 28, 90, and 180 days, respectively. Serum IL-8 levels were only an independent predictor of 28-day mortality and could simply classify ACLF patients. Conversely, mean arterial pressure (MAP), HBV-DNA, and COSHACLF IIs were independent predictors of mortality across all three observation periods. We constructed a nomogram based on IL-8 that was able to visualise and predict 28-day mortality with a C-index of 0.901 (95% CI: 0.862-0.940). Our calibration curves, Predicted Probability of Death & Actual Survival Status plot, and Confusion Matrix demonstrated the nomogram model's strong predictive power. DCA indicated the nomogram's promising clinical utility in predicting 28-day mortality in ACLF patients.

CONCLUSION

Serum IL-8 levels predict short-term mortality in ACLF patients in the background of HBV-associated cirrhosis, and the developed Nomogram model has strong predictive power and good clinical utility.

Consensus document on acute-on-chronic liver failure (ACLF) established by the Mexican Association of Hepatology

Acute-on chronic liver failure (ACLF) has been an intensively debated topic mainly due to the lack of a unified definition and diagnostic criteria. The growing number of publications describing the mechanisms of ACLF development, the progression of the disease, outcomes and treatment has contributed to a better understanding of the disease, however, it has also sparked the debate about this condition. As an attempt to provide medical professionals with a more uniform definition that could be applied to our population, the first Mexican consensus was performed by a panel of experts in the area of hepatology in Mexico. We used the most relevant and impactful publications along with the clinical and research experience of the consensus participants. The consensus was led by 4 coordinators who provided the most relevant bibliography by doing an exhaustive search on the topic. The entire bibliography was made available to the members of the consensus for consultation at any time during the process and six working groups were formed to develop the following sections: 1.- Generalities, definitions, and criteria, 2.- Pathophysiology of cirrhosis, 3.- Genetics in ACLF, 4.- Clinical manifestations, 5.- Liver transplantation in ACLF, 6.- Other treatments.

Haemostasis in cirrhosis: Understanding destabilising factors during acute decompensation

Hospitalised patients with decompensated cirrhosis are in a rebalanced haemostatic state due to a parallel decline in both pro- and anti-haemostatic pathways. However, this rebalanced haemostatic state is highly susceptible to perturbations and may easily tilt towards hypocoagulability and bleeding. Acute kidney injury, bacterial infections and sepsis, and progression from acute decompensation to acute-on-chronic liver failure are associated with additional alterations of specific haemostatic pathways and a higher risk of bleeding. Unfortunately, there is no single laboratory method that can accurately stratify an individual patient's bleeding risk and guide pre-procedural prophylaxis. A better understanding of haemostatic alterations during acute illness would lead to more rational and individualised management of hospitalised patients with decompensated cirrhosis. This review will outline the latest findings on haemostatic alterations driven by acute kidney injury, bacterial infections/sepsis, and acute-on-chronic liver failure in these difficult-to-treat patients and provide evidence supporting more tailored management of bleeding risk.

Response Guided Slow Infusion of Albumin, Vasoconstrictors and Furosemide Improves Ascites Mobilization and Survival in Acute on Chronic Liver Failure: A Proof-of-Concept Study

Background and Aims

Acute-on-chronic liver failure (ACLF) with increasing organ failure is associated with poor outcomes. Severely deranged systemic hemodynamics and decreased effective arterial blood volume contribute to tissue damage and organ failure. Response-guided therapy with albumin, vasoconstrictors, and furosemide may help overcome effective hypovolemia, improve diuresis and impact survival.

Methods

In the observation cohort, 230 patients with ACLF (CANONIC criteria) with ascites (≥Grade II) and ACLF ≥Grade I were enrolled. A total of 136 patients (GROUP I) received response-guided (urine sodium >80mmol/day) slow albumin-furosemide infusion ± terlipressin (SAFI ± T), while 94 patients (GROUP II) received standard medical therapy. Twenty-eight-day survival, ascites mobilization (nil or grade 1), and adverse events were noted. In another mechanistic cohort (n = 40), laboratory evidences for improvement in various pathophysiological alterations; gut permeability, endotoxemia, cytokine storm, neutrophil dysfunction, and hemodynamic alterations following SAFI ± T/Noradrenaline (NAdr) were evaluated.

Results

Age, gender, CLIF-C-ACLF, SOFA and MELD scores, ACLF grades and urine sodium were not different between the two groups in the observation cohort. Ascites was mobilized in 102/136 in GROUP I (SAFI ± T) and 23/94 in GROUP II (p < 0.05). Twenty-eight-day survival was significantly higher in GROUP I = 103/136 (75.7%) vs GROUP II = 50/94 (53.2%), (P = <0.001). All those who were unable to reach urine sodium >80 mmol/day died. Four patients in GROUP I developed scrotal gangrene. In the mechanistic cohort, 72% of patients survived with significant improvement in gut permeability, endotoxemia, serum cytokines, neutrophil dysfunction, and hemodynamic alterations.

Conclusion

Ascitic fluid mobilization by response-guided SAFI ± T/NAdr therapy improves survival by improving splanchnic and systemic hemodynamics, decreasing gut congestion, gut permeability, and endotoxemia, improving neutrophil functions, and reducing pro-inflammatory cytokines in circulation.

Acute-on-Chronic Liver Failure Clinical Guidelines

In patients with cirrhosis and chronic liver disease, acute-on-chronic liver failure is emerging as a major cause of mortality. These guidelines indicate the preferred approach to the management of patients with acute-on-chronic liver failure and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation process. In instances where the evidence was not appropriate for Grading of Recommendations, Assessment, Development, and Evaluation, but there was consensus of significant clinical merit, key concept statements were developed using expert consensus. These guidelines are meant to be broadly applicable and should be viewed as the preferred, but not only, approach to clinical scenarios.

Hepatorenal syndrome in acute-on-chronic liver failure with acute kidney injury: more questions requiring discussion

In cirrhosis with ascites, hepatorenal syndrome (HRS) is a specific prerenal dysfunction unresponsive to fluid volume expansion. Acute-on-chronic liver failure (ACLF) comprises a group of clinical syndromes with multiple organ failure and early high mortality. There are differences in the characterization of ACLF between the Eastern and Western medical communities. Patients with ACLF and acute kidney injury (AKI) have more structural injuries, contributing to confusion in diagnosing HRS-AKI. In this review, we discuss progress in the pathogenesis, diagnosis, and management of HRS-AKI, especially in patients with ACLF. Controversy regarding HRS-AKI in ACLF and acute liver failure, hepatic carcinoma, shock, sepsis, and chronic kidney disease is also discussed. Research on the treatment of HRS-AKI with ACLF needs to be more actively pursued to improve disease prognosis.

Hepatitis E virus infection in a patient with alcohol related chronic liver disease: a case report of acute-on-chronic liver failure

Background

The hepatitis E virus (HEV) infection has been described as a causing factor for acute-on-chronic-liver-failure (ACLF) in patients with underlying chronic liver disease (CLD), such as chronic hepatitis or cirrhosis, which could end in the failure of one or more organs and high short-term mortality. There are scarce data about the association of HEV in patients with chronic liver disorders in South America.

Case presentation

A 56-year-old hypertensive male with a history of type 2 diabetes was diagnosed with alcohol-related-liver cirrhosis in February 2019. A year later, the patient was admitted to hospital due to fatigue, jaundice and acholia. No evidence of hepatitis A virus, hepatitis B virus, hepatitis C virus, Epstein–Barr virus, herpes zoster virus and cytomegalovirus infections were found. Nevertheless, in February and March, 2020 the patient was positive for HEV-IgM and HEV-IgG, and HEV genotype 3 RNA was detected in sera. Afterwards, he presented grade I hepatic encephalopathy and, therefore, was diagnosed with acute hepatitis E-on-chronic liver disease. The patient reported a recent travel to the Argentine coast, where he consumed seafood. Besides, he reveled to have consumed pork meat and had no history of blood transfusion.

Conclusion

This report describes a unique case of hepatitis E virus infection in a patient with alcohol-related cirrhosis. This is the first report of a patient with HEV-related ACLF in Argentina and it invokes the importance of HEV surveillance and treatment among patients with CLD, such as alcohol-related cirrhosis.

Transition to decompensation and acute-on-chronic liver failure: Role of predisposing factors and precipitating events

The transition from compensated to decompensated cirrhosis results from a complex interplay of predisposing and precipitating factors and represents an inflection point in the probability of a patient surviving. With the progression of cirrhosis, patients accumulate multiple disorders (e.g. altered liver architecture, portal hypertension, local and systemic inflammation, bacterial translocation, gut dysbiosis, kidney vasoconstriction) that predispose them to decompensation. On the background of these factors, precipitating events (e.g. bacterial infection, alcoholic hepatitis, variceal haemorrhage, drug-induced liver injury, flare of liver disease) lead to acute decompensation (ascites, hepatic encephalopathy, variceal bleeding, jaundice) and/or organ failures, which characterise acute-on-chronic liver failure. In this review paper, we will discuss the current hypotheses and latest evidences regarding predisposing and precipitating factors associated with the transition to decompensated liver disease.

Liver perfusion MRI in a rodent model of cirrhosis: Agreement with bulk-flow phase-contrast MRI and noninvasive evaluation of inflammation in chronic liver disease using flow-sensitive alternating inversion recovery arterial spin labelling and tissue T1

Noninvasive measurements of liver perfusion and fibrosis in cirrhotic small animals can help develop treatments for haemodynamic complications of liver disease. Here, we measure liver perfusion in cirrhotic rodents using flow-sensitive alternating inversion recovery arterial spin labelling (FAIR ASL), evaluating agreement with previously validated caval subtraction phase-contrast magnetic resonance imaging (PCMRI) total liver blood flow (TLBF). Baseline differences in cirrhotic rodents and the haemodynamic effects of acute inflammation were investigated using FAIR ASL and tissue T1. Sprague-Dawley rats (nine bile duct ligated [BDL] and ten sham surgery controls) underwent baseline hepatic FAIR ASL with T1 measurement and caval subtraction PCMRI (with two-dimensional infra-/supra-hepatic inferior vena caval studies), induction of inflammation with intravenous lipopolysaccharide (LPS) and repeat liver FAIR ASL with T1 measurement after ~90 minutes. The mean difference between FAIR ASL hepatic perfusion and caval subtraction PCMRI TLBF was -51 ± 30 ml/min/100 g (Bland-Altman 95% limits-of-agreement ±258 ml/min/100 g). The FAIR ASL coefficient of variation was smaller than for caval subtraction PCMRI (29.3% vs 50.1%; P = .03). At baseline, FAIR ASL liver perfusion was lower in BDL rats (199 ± 32 ml/min/100 g vs sham 316 ± 24 ml/min/100 g; P = .01) but liver T1 was higher (BDL 1533 ± 50 vs sham 1256 ± 18 ms; P = .0004). Post-LPS FAIR ASL liver perfusion response differences were observed between sham/BDL rats (P = .02), approaching significance in sham (+78 ± 33 ml/min/100 g; P = .06) but not BDL rats (-49 ± 40 ml/min/100 g; P = .47). Post-LPS differences in liver tissue T1 were nonsignificant (P = .35). FAIR ASL hepatic perfusion and caval subtraction PCMRI TLBF agreement was modest, with significant baseline FAIR ASL liver perfusion and tissue T1 differences in rodents with advanced cirrhosis compared with controls. Following inflammatory stress, differences in hepatic perfusion response were detected between cirrhotic/control animals, but liver T1 was unaffected. Findings underline the potential of FAIR ASL in the assessment of vasoactive treatments for patients with chronic liver disease and inflammation.

Midodrine Improves the Tolerability of Diuretics in Patients with Acute-on-Chronic Liver Failure-A Pilot Study

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a syndrome of acute portal hypertension with high short-term mortality. ACLF patients have low mean arterial pressure (MAP), systemic vascular resistance, and high cardiac output. This, in turn, leads to an increased incidence of ascites, acute kidney injury, and hyponatremia. We evaluated the role of the early addition of midodrine, which has not been analyzed to date.

METHODS

ACLF patients who were started on midodrine (Gr. A) in addition to standard of care (SOC) for ascites control were included and compared with those who received only SOC (Gr. B). The aim was to assess the hemodynamics, ascites control, diuretic-related complications, and mortality at 1 month.

RESULTS

Forty-five ACLF patients (Gr. A-21; Gr. B-24) were included in the pilot study. At inclusion, the baseline characteristics were similar among the groups. The dose of midodrine was 22.5 (7.5-22.5) mg/day for 22.29 ± 8.75 days in Gr. A. Midodrine significantly improved the MAP and urinary sodium excretion. Only 33.34% of patients required paracentesis in Gr. A compared with 62.5% in Gr. B (p = 0.05). Gr. A patients tolerated a higher dose of diuretics than Gr. B. Diuretic-related complications developed in 54.2% of patients in Gr. B compared with only 23.8% in Gr. A (p = 0.03). Fourteen percent in Gr. A developed side effects to midodrine and required dose modification. Mortality at day 30 was similar in both groups.

CONCLUSION

Addition of midodrine improves the hemodynamics, tolerability of diuretics, and ascites control in ACLF patients.

Haemodynamic changes in cirrhosis following terlipressin and induction of sepsis-a preclinical study using caval subtraction phase-contrast and cardiac MRI

Objectives

Effects of liver disease on portal venous (PV), hepatic arterial (HA), total liver blood flow (TLBF), and cardiac function are poorly understood. Terlipressin modulates PV flow but effects on HA, TLBF, and sepsis/acute-on-chronic liver failure (ACLF)-induced haemodynamic changes are poorly characterised. In this study, we investigated the effects of terlipressin and sepsis/ACLF on hepatic haemodynamics and cardiac function in a rodent cirrhosis model using caval subtraction phase-contrast (PC) MRI and cardiac cine MRI.

Methods

Sprague-Dawley rats (n = 18 bile duct–ligated (BDL), n = 16 sham surgery controls) underwent caval subtraction PCMRI to estimate TLBF and HA flow and short-axis cardiac cine MRI for systolic function at baseline, following terlipressin and lipopolysaccharide (LPS) infusion, to model ACLF.

Results

All baseline hepatic haemodynamic/cardiac systolic function parameters (except heart rate and LV mass) were significantly different in BDL rats. Following terlipressin, baseline PV flow (sham 181.4 ± 12.1 ml/min/100 g; BDL 68.5 ± 10.1 ml/min/100 g) reduced (sham − 90.3 ± 11.1 ml/min/100 g, p < 0.0001; BDL − 31.0 ± 8.0 ml/min/100 g, p = 0.02), sham baseline HA flow (33.0 ± 11.3 ml/min/100 g) increased (+ 92.8 ± 21.3 ml/min/100 g, p = 0.0003), but BDL baseline HA flow (83.8 ml/min/100 g) decreased (− 34.4 ± 7.5 ml/min/100 g, p = 0.11). Sham baseline TLBF (214.3 ± 16.7 ml/min/100 g) was maintained (+ 2.5 ± 14.0 ml/min/100 g, p > 0.99) but BDL baseline TLBF (152.3 ± 18.7 ml/min/100 g) declined (− 65.5 ± 8.5 ml/min/100 g, p = 0.0004). Following LPS, there were significant differences between cohort and change in HA fraction (p = 0.03) and TLBF (p = 0.01) with BDL baseline HA fraction (46.2 ± 4.6%) reducing (− 20.9 ± 7.5%, p = 0.03) but sham baseline HA fraction (38.2 ± 2.0%) remaining unchanged (+ 2.9 ± 6.1%, p > 0.99). Animal cohort and change in systolic function interactions were significant only for heart rate (p = 0.01) and end-diastolic volume (p = 0.03).

Conclusions

Caval subtraction PCMRI and cardiac MRI in a rodent model of cirrhosis demonstrate significant baseline hepatic haemodynamic/cardiac differences, failure of the HA buffer response post-terlipressin and an altered HA fraction response in sepsis, informing potential translation to ACLF patients.

Key Points

Caval subtraction phase-contrast and cardiac MRI demonstrate:

• Significant differences between cirrhotic/non-cirrhotic rodent hepatic blood flow and cardiac systolic function at baseline.

• Failure of the hepatic arterial buffer response in cirrhotic rodents in response to terlipressin.

• Reductions in hepatic arterial flow fraction in the setting of acute-on-chronic liver failure.

Viral Hepatitis E and Chronicity: A Growing Public Health Concern

Hepatitis E viral infection recently emerges as a global health concern. Over the last decade, the understanding of hepatitis E virus (HEV) had changed with the discovery of new genotypes like genotype-7 and genotype-8 with associated host and mode of infection. Diversification in the mode of hepatitis E infection transmission through blood transfusion, and organ transplants in contrast to classical feco-oral and zoonotic mode is the recent medical concern. The wide spectrum of infection ranging from self-limiting to acute liver failure is now overpowered by HEV genotype-specific chronic infection especially in transplant patients. This concern is further escalated by the extra-hepatic manifestations of HEV targeting the central nervous system (CNS), kidney, heart, and pancreas. However, with the development of advanced efficient cell culture systems and animal models simulating the infection, much clarity toward understanding the pathogenetic mechanism of HEV has been developed. Also this facilitates the development of vaccines research or therapeutics. In this review, we highlight all the novel findings in every aspect of HEV with special emphasis on recently emerging chronic mode of infection with specific diagnosis and treatment regime with an optimistic hope to help virologists and/or liver specialists working in the field of viral hepatitis.

Paracentesis-Induced Circulatory Dysfunction With Modest-Volume Paracentesis Is Partly Ameliorated by Albumin Infusion in Acute-on-Chronic Liver Failure

BACKGROUND AND AIMS

Paracentesis-induced circulatory dysfunction (PICD) is a serious complication of large-volume (>5 L) paracentesis in cirrhosis and is reduced with albumin infusion. There is a lack of data on PICD in acute-on-chronic liver failure (ACLF). Because ACLF patients have greater hemodynamic derangements than patients with decompensated cirrhosis, we investigated whether PICD could develop with modest-volume paracentesis (MVP) and the role of albumin infusion.

APPROACH AND RESULTS

A total of 80 ACLF patients undergoing <5 L paracentesis were randomized to receive albumin (8 g/dL of ascitic fluid; n = 40) or no albumin (n = 40) and serially followed to detect PICD. Baseline characteristics were comparable between groups, including volume of ascitic tap (4.16 ± 0.23 versus 4.14 ± 0.27 L; P = 0.72) and plasma renin activity (PRA; 20.5 ± 7.03 versus 23.2 ± 8.24 ng/mL/hour; P = 0.12). PICD was more frequent in the no-albumin group than the albumin group (70% versus 30%; P = 0.001), with higher incidence of hepatic encephalopathy (50% versus 27.5%; P = 0.04), hyponatremia (67.5% versus 22.5%; P < 0.001), acute kidney injury (62.5% versus 30%; P = 0.001), and in-house mortality (62.5% versus 27.5%; P = 0.003). PRA of 25.15 ng/mL at day 3 had sensitivity and specificity of 71% and 68%, respectively, for development of PICD at day 6. Albumin infusion decreased the incidence of PICD at day 6 (odds ratio, 0.068; 95% confidence interval, 0.011-0.43; P = 0.005).

CONCLUSIONS

PICD is common and develops even with MVP in ACLF patients. Albumin infusion decreases the incidence of PICD and mortality in patients with ACLF. Clinical trial identifier: NCT02467348.

Approach to the liver transplant early postoperative period: an institutional standpoint

The liver transplant program in our center started in 1992, and post-liver transplant patients are still admitted to the intensive care unit. For the intensive care physician, a learning curve started then, skills were acquired, and a specific practice was established. Throughout this time, several concepts changed, improving the care of these patients. The practical approach varies between liver transplant centers, according to local specificities. Hence, we wanted to present our routine practice to stimulate the debate between dedicated teams, which can allow the introduction of new ideas and potentially improve each local standard of care.

Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific association for the study of the liver (APASL): an update

The first consensus report of the working party of the Asian Pacific Association for the Study of the Liver (APASL) set up in 2004 on acute-on-chronic liver failure (ACLF) was published in 2009. With international groups volunteering to join, the "APASL ACLF Research Consortium (AARC)" was formed in 2012, which continued to collect prospective ACLF patient data. Based on the prospective data analysis of nearly 1400 patients, the AARC consensus was published in 2014. In the past nearly four-and-a-half years, the AARC database has been enriched to about 5200 cases by major hepatology centers across Asia. The data published during the interim period were carefully analyzed and areas of contention and new developments in the field of ACLF were prioritized in a systematic manner. The AARC database was also approached for answering some of the issues where published data were limited, such as liver failure grading, its impact on the 'Golden Therapeutic Window', extrahepatic organ dysfunction and failure, development of sepsis, distinctive features of acute decompensation from ACLF and pediatric ACLF and the issues were analyzed. These initiatives concluded in a two-day meeting in October 2018 at New Delhi with finalization of the new AARC consensus. Only those statements, which were based on evidence using the Grade System and were unanimously recommended, were accepted. Finalized statements were again circulated to all the experts and subsequently presented at the AARC investigators meeting at the AASLD in November 2018. The suggestions from the experts were used to revise and finalize the consensus. After detailed deliberations and data analysis, the original definition of ACLF was found to withstand the test of time and be able to identify a homogenous group of patients presenting with liver failure. New management options including the algorithms for the management of coagulation disorders, renal replacement therapy, sepsis, variceal bleed, antivirals and criteria for liver transplantation for ACLF patients were proposed. The final consensus statements along with the relevant background information and areas requiring future studies are presented here.

An update on the pathogenesis and clinical management of cirrhosis with refractory ascites

Ascites commonly complicates cirrhosis, becoming refractory to treatment with diuretics and sodium restriction in approximately 10% of patients. Pathogenesis of refractory ascites (RA) is multifactorial, the common final pathway being renal hypoperfusion and avid sodium retention. Refractory ascites has a negative prognostic implication in the natural history of cirrhosis. Management of RA include sodium restriction and regular large volume paracentesis (LVP) with albumin infusions, preventing paracentesis-induced circulatory dysfunction. In appropriate setting, transjugular intrahepatic porto-systemic shunt (TIPS) can be considered. Ascites clearance with TIPS can lead to nutritional improvement, avoiding sarcopenia. Liver transplantation (LT) remains the definitive treatment for eligible candidates. Areas covered: Our review summarizes current updates on pathogenesis and clinical management of RA including potential future therapeutic options such as the automated slow-flow ascites pump, chronic outpatient albumin infusion and cell-free and concentrated ascites reinfusion therapy. Expert commentary: Standard of care in patients with RA include LVP with albumin replacement and prompt referral for LT where indicated. Other novel therapeutic options on the horizon include automated low-flow ascites pump and cell-free, concentrated albumin reinfusion therapy.

Liver transplantation for critically ill cirrhotic patients: Overview and pragmatic proposals

Liver transplantation for critically ill cirrhotic patients with acute deterioration of liver function associated with extrahepatic organ failures is controversial. While transplantation has been shown to be beneficial on an individual basis, the potentially poorer post-transplant outcome of these patients taken as a group can be held as an argument against allocating livers to them. Although this issue concerns only a minority of liver transplants, it calls into question the very heart of the allocation paradigms in place. Indeed, most allocation algorithms have been centered on prioritizing the sickest patients by using the model for end-stage liver disease score. This has led to allocating increasing numbers of livers to increasingly critically ill patients without setting objective or consensual limits on how sick patients can be when they receive an organ. Today, finding robust criteria to deem certain cirrhotic patients too sick to be transplanted seems urgent in order to ensure the fairness of our organ allocation protocols. This review starts by fleshing out the argument that finding such criteria is essential. It examines five types of difficulties that have hindered the progress of recent literature on this issue and identifies various strategies that could be followed to move forward on this topic, taking into account the recent discussion on acute on chronic liver failure. We move on to review the literature along four axes that could guide clinicians in their decision-making process regarding transplantation of critically ill cirrhotic patients.

A return to harmful alcohol consumption impacts on portal hemodynamic changes following alcoholic hepatitis

BACKGROUND

Increased hepatic venous pressure gradient (HVPG) plays a role in the clinical manifestations of alcoholic hepatitis (AH). The evolution of HVPG and the influence of alcohol use in the intermediate term are unclear.

AIM

The aim of this study was to explore HVPG modifications following AH taking into consideration alcohol use and clinical manifestations.

PATIENTS AND METHODS

Patients with AH (n=37; age 52 years; model for end-stage liver disease: 18.5; Maddrey score: 43) and chronic excessive drinkers with compensated cirrhosis (n=19; age: 54 years; model for end-stage liver disease: 9.2) underwent HVPG measurement and liver biopsy. Ten long-standing abstinent alcoholic cirrhotics served as controls. After discharge, patients were monitored for alcohol use and clinical complications, with repeated HVPG after a median duration of 100 days. Inflammation was determined using plasma C-reactive protein.

RESULTS

At baseline, compared with chronic excessive drinkers and alcoholic cirrhotics, patients with AH had increased HVPG (18.1±0.6 vs. 13.8±1.4 vs. 15±1.3 mmHg, P<0.05). During follow-up, patients who became abstinent or reported occasional drinking were more likely to achieve a greater than 20% reduction in HVPG compared with those returning to harmful alcohol (45 vs. 0%, P<0.01), and suffered from fewer complications (25 vs. 68%, P<0.03). High baseline C-reactive protein levels correlated to the Maddrey (r=0.38), but no relationship was observed between changes in inflammation and HVPG.

CONCLUSION

Elevated HVPG is a feature of AH, with a clinically significant reduction in values in abstinent or occasional drinkers after weeks of follow-up. A return to harmful alcohol has a negative impact on portal hemodynamics and associated clinical complications.

Role of Hepatitis E Virus Infection in Acute-on-Chronic Liver Failure

Chronic liver disease (CLD) with a variety of causes is currently reported to be one of the main causes of death worldwide. Patients with CLD experience deteriorating liver function and fibrosis, progressing to cirrhosis, chronic hepatic decompensation (CHD), end-stage liver disease (ESLD), and death. Patients may develop acute-on-chronic liver failure (ACLF), typically related to a precipitating event and associated with increased mortality. The objective of this review was to analyze the role of acute hepatitis E virus (HEV) infection in patients with CLD, focusing on the impact of this infection on patient survival and prognosis in several world regions.

Copeptin in acute decompensation of liver cirrhosis: relationship with acute-on-chronic liver failure and short-term survival

Background

Acute-on-chronic liver failure (ACLF) is characterized by the presence of acute decompensation (AD) of cirrhosis, organ failure, and high short-term mortality rates. Hemodynamic dysfunction and activation of endogenous vasoconstrictor systems are thought to contribute to the pathogenesis of ACLF. We explored whether copeptin, a surrogate marker of arginine vasopressin, is a potential marker of outcome in patients admitted for AD or ACLF and whether it might be of additional value to conventional prognostic scoring systems in these patients.

Methods

All 779 patients hospitalized for AD of cirrhosis from the CANONIC database with at least one serum sample available for copeptin measurement were included. Presence of ACLF was defined according to the CLIF-consortium organ failure (CLIF-C OF) score. Serum copeptin was measured in samples collected at days 0–2, 3–7, 8–14, 15–21, and 22–28 when available. Competing-risk regression analysis was applied to evaluate the impact of serum copeptin and laboratory and clinical data on short-term survival.

Results

Serum copeptin concentration was found to be significantly higher in patients with ACLF compared with those without ACLF at days 0–2 (33 (14–64) vs. 11 (4–26) pmol/L; p < 0.001). Serum copeptin at admission was shown to be a predictor of mortality independently of MELD and CLIF-C OF scores. Moreover, baseline serum copeptin was found to be predictive of ACLF development within 28 days of follow-up.

Conclusions

ACLF is associated with significantly higher serum copeptin concentrations at hospital admission compared with those with traditional AD. Copeptin is independently associated with short-term survival and ACLF development in patients admitted for AD or ACLF.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1894-8) contains supplementary material, which is available to authorized users.

Acute-on-chronic liver failure: recent update

Acute on chronic liver failure (ACLF) was first described in 1995 as a clinical syndrome distinct to classic acute decompensation. Characterized by complications of decompensation, ACLF occurs on a background of chronic liver dysfunction and is associated with high rates of organ failure and significant short-term mortality estimated between 45% and 90%. Despite the clinical relevance of the condition, it still remains largely undefined with continued disagreement regarding its precise etiological factors, clinical course, prognostic criteria and management pathways. It is concerning that, despite our relative lack of understanding of the condition, the burden of ACLF among cirrhotic patients remains significant with an estimated prevalence of 30.9%. This paper highlights our current understanding of ACLF, including its etiology, diagnostic and prognostic criteria and pathophysiology. It is evident that further refinement of the ACLF classification system is required in order to detect high-risk patients and improve short-term mortality rates. The field of metabolomics certainly warrants investigation to enhance diagnostic and prognostic parameters, while the use of granulocyte-colony stimulating factor is a promising future therapeutic intervention for patients with ACLF.

Reviewing the diagnostic criteria for acute-on-chronic liver failure

For over 20 years, acute-on-chronic liver failure (ACLF) has taken multiple definitions and/or classifications. The definition outlines the acute and chronic insults to include a homogenous patient group with liver failure and an expected outcome in a specific time frame. Early and accurate diagnosis is essential as this inflammation of the liver may tilt the balance of liver destruction and regeneration adversely. Various factors such as superadded systemic sepsis, liver reserve, cause of primary chronic liver disease, state of immune system or the state of gut microbial flora might determine the ultimate prognosis. Areas covered: To date, there has been no universally accepted definition of ACLF. In this review, we discuss the strengths and weaknesses, controversies and basis for early identification and accurate diagnosis of ACLF. PubMed and Google scholar database searches were conducted, search terms included 'acute on chronic liver failure,' 'ACLF,' and 'diagnostic criteria.' Expert commentary: With recent advances in the management of advanced cirrhosis, research will gradually shift towards ACLF in the near future, focusing on the pathogenesis, new treatment options and improving survival. Once we improve understanding of this syndrome, newer definitions will evolve, thereby enabling earlier diagnosis and novel therapeutic avenues.

Overview on acute-on-chronic liver failure

Liver failure (LF) is defined as severe dysfunction in hepatic synthesis, detoxification, and metabolism induced by various etiologies. Clinical presentation of LF typically includes severe jaundice, coagulation disorder, hepatic encephalopathy, and ascites. LF can be classified into acute LF, acute-on-chronic LF (ACLF), and chronic LF. ACLF has been demonstrated as a distinct syndrome with unique clinical presentation and outcomes. The severity, curability, and reversibility of ACLF have attracted considerable attention. Remarkable developments in ACLF-related conception, diagnostic criteria, pathogenesis, and therapy have been achieved. However, this disease, especially its diagnostic criteria, remains controversial. In this paper, we systemically reviewed the current understanding of ACLF from its definition, etiology, pathophysiology, pathology, and clinical presentation to management by thoroughly comparing important findings between east and west countries, as well as those from other regions. We also discussed the controversies, challenges, and needs for future studies to promote the standardization and optimization of the diagnosis and treatment for ACLF.

Acute-on-chronic liver failure: terminology, mechanisms and management

Acute-on-chronic liver failure (ACLF) is a distinct clinical entity and differs from acute liver failure and decompensated cirrhosis in timing, presence of acute precipitant, course of disease and potential for unaided recovery. The definition involves outlining the acute and chronic insults to include a homogenous patient group with liver failure and an expected outcome in a specific timeframe. The pathophysiology of ACLF relates to persistent inflammation, immune dysregulation with initial wide-spread immune activation, a state of systematic inflammatory response syndrome and subsequent sepsis due to immune paresis. The disease severity and outcome can be predicted by both hepatic and extrahepatic organ failure(s). Clinical recovery is expected with the use of nucleoside analogues for hepatitis B, and steroids for severe alcoholic hepatitis and, possibly, severe autoimmune hepatitis. Artificial liver support systems help remove toxins and metabolites and serve as a bridge therapy before liver transplantation. Hepatic regeneration during ongoing liver failure, although challenging, is possible through the use of growth factors. Liver transplantation remains the definitive treatment with a good outcome. Pre-emptive antiviral agents for hepatitis B before chemotherapy to prevent viral reactivation and caution in using potentially hepatotoxic drugs can prevent the development of ACLF.

Influence of variceal bleeding on natural history of ACLF and management options

Patients with diagnosed and undiagnosed chronic liver diseases experience one or more acute assaults of a hepatic nature and develop a downhill course of liver diseases, a condition regarded as acute-on-chronic liver failure (ACLF). It is a medical emergency, the prognosis of ACLF is extremely bad and considerable numbers of patients with ACLF die even after diagnosis and receiving conservative treatment. ACLF is characterized by jaundice, coagulopathy, ascites and encephalopathy. ACLF patients are very sick and associated with different hemodynamic profiles and have very high 3-month mortality. As these groups of patients have high baseline hepatic venous pressure gradients, the chances of variceal bleed are also high, and the impact is also greater in comparison to stable cirrhosis; however, evidence is lacking to substantiate such effects. The aim of this review is to discuss the natural course of variceal bleeding in ACLF patients and to develop insights into the management of variceal bleeding in ACLF.

Acute-on-chronic liver failure: Pathogenesis, prognostic factors and management

Acute-on-chronic liver failure (ACLF) is increasingly recognized as a complex syndrome that is reversible in many cases. It is characterized by an acute deterioration of liver function in the background of a pre-existing chronic liver disease often associated with a high short-term mortality rate. Organ failure (OF) is always associated, and plays a key role in determining the course, and the outcome of the disease. The definition of ACLF remains controversial due to its overall ambiguity, with several disparate criteria among various associations dedicated to the study of liver diseases. Although the precise pathogenesis needs to be clarified, it appears that an altered host response to injury might be a contributing factor caused by immune dysfunction, ultimately leading to a pro-inflammatory status, and eventually to OF. The PIRO concept (Predisposition, Insult, Response and Organ Failure) has been proposed to better approach the underlying mechanisms. It is accepted that ACLF is a different and specific form of liver failure, where a precipitating event is always involved, even though it cannot always be ascertained. According to several studies, infections and active alcoholism often trigger ACLF. Viral hepatitis, gastrointestinal haemorrhage, or drug induced liver injury, which can also provoke the syndrome. This review mainly focuses on the physiopathology and prognostic aspects. We believe these features are essential to further understanding and providing the rationale for improveddisease management strategies.

Cirrhotic Multiorgan Syndrome

Patients with cirrhosis and portal hypertension are at an increased risk of the development of circulatory dysfunction that may potentially result in multiple organ failure. Apart from the liver, this may involve the heart, lungs, kidneys, the immune system, the adrenal glands, and other organ systems. As the disease progresses, the circulation becomes hyperdynamic, and signs of cardiac, pulmonary, and renal dysfunction are observed, in addition to reduced survival. Infections and an altered cardiac function known as cirrhotic cardiomyopathy may be precipitators for the development of other complications such as hepatorenal syndrome. In patients with chronic organ dysfunction, various precipitating events may induce an acute-on-chronic renal failure and acute-on-chronic liver failure that negatively affect the prognosis. Future research on the pathophysiologic mechanisms of the complications and the precipitating factors is essential to understand the basics of the treatment of these challenging conditions. The aim of the present review is to focus on the development and precipitating factors of various organ failures in patients with decompensated cirrhosis.

Systemic inflammation is associated with increased intrahepatic resistance and mortality in alcohol-related acute-on-chronic liver failure

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is characterized by acute deterioration of cirrhosis, systemic inflammation and multi-organ failure. Inflammation is also key to the pathobiology of portal hypertension. This study aims to define the relationship between systemic and hepatic haemodynamics in patients with ACLF.

METHODS

Sixty patients with alcoholic cirrhosis were prospectively enrolled - stable cirrhosis (SC, n = 27), acute decompensation without ACLF (AD, n = 14) and ACLF (n = 19) - and managed with standard therapy. Systemic and hepatic haemodynamic studies were performed, and patients were followed up for 3 months. Plasma norepinephrine, cytokine profile, nitrate/nitrite and malondialdehyde levels were measured.

RESULTS

Three-month mortality was as follows: SC - none; AD - 14%; ACLF - 47.2% (P < 0.001). Mean arterial pressure was lowest in the ACLF group (P < 0.001). ACLF patients had significantly higher hepatic vein pressure gradient (HVPG), while the hepatic blood flow was markedly reduced with an increase in intrahepatic resistance, which predicted mortality (AUROC: 0.87, P < 0.0001). In ACLF, the severity of intrahepatic resistance correlated with markers of inflammatory response, norepinephrine levels, creatinine levels and severity of encephalopathy. Modelling data showed that the high norepinephrine levels in ACLF may contribute to the right shift of the HVPG-hepatic blood flow relationship and its levels correlated with inflammatory markers and mortality (AUROC: 0.90; P < 0.0001).

CONCLUSIONS

The disturbances in systemic and hepatic haemodynamics in alcohol-related ACLF are associated with dysregulated inflammation, multi-organ failure and marked activation of the sympathetic nervous system. These abnormalities predict high mortality rates in alcohol-related ACLF patients.

Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific Association for the Study of the Liver (APASL) 2014

The first consensus report of the working party of the Asian Pacific Association for the Study of the Liver (APASL) set up in 2004 on acute-on-chronic liver failure (ACLF) was published in 2009. Due to the rapid advancements in the knowledge and available information, a consortium of members from countries across Asia Pacific, "APASL ACLF Research Consortium (AARC)," was formed in 2012. A large cohort of retrospective and prospective data of ACLF patients was collated and followed up in this data base. The current ACLF definition was reassessed based on the new AARC data base. These initiatives were concluded on a 2-day meeting in February 2014 at New Delhi and led to the development of the final AARC consensus. Only those statements which were based on the evidence and were unanimously recommended were accepted. These statements were circulated again to all the experts and subsequently presented at the annual conference of the APASL at Brisbane, on March 14, 2014. The suggestions from the delegates were analyzed by the expert panel, and the modifications in the consensus were made. The final consensus and guidelines document was prepared. After detailed deliberations and data analysis, the original proposed definition was found to withstand the test of time and identify a homogenous group of patients presenting with liver failure. Based on the AARC data, liver failure grading, and its impact on the "Golden therapeutic Window," extra-hepatic organ failure and development of sepsis were analyzed. New management options including the algorithms for the management of coagulation disorders, renal replacement therapy, sepsis, variceal bleed, antivirals, and criteria for liver transplantation for ACLF patients were proposed. The final consensus statements along with the relevant background information are presented here.

Acute-on-chronic liver failure: a review

There is no universally accepted definition of acute-on-chronic liver failure; however, it is recognized as an entity characterized by decompensation from an underlying chronic liver disease associated with organ failure that conveys high short-term mortality, with alcoholism and infection being the most frequent precipitating events. The pathophysiology involves inflammatory processes associated with a trigger factor in susceptible individuals (related to altered immunity in the cirrhotic population). This review addresses the different definitions developed by leading research groups, epidemiological and pathophysiological aspects, and the latest treatments for this entity.

Acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is an increasingly recognized distinct disease entity encompassing an acute deterioration of liver function in patients with chronic liver disease. Although there are no widely accepted diagnostic criteria for ACLF, the Asia.Pacific Association for the Study of the Liver (APASL) and the American Association for the Study of Liver Disease and the European Association for the Study of the Liver (AASLD/EASL) consensus definitions are commonly used. It is obvious that the APASL and the AASLD/EASL definitions are based on fundamentally different features. Two different definitions in two different parts of the world hamper the comparability of studies. Recently, the EASL-Chronic Liver Failure Consortium proposed new diagnostic criteria for ACLF based on analyses of patients with organ failure. There are areas of uncertainty in defining ACLF, such as heterogeneity of ACLF, ambiguity in qualifying underlying liver disease, argument for infection or sepsis as a precipitating event, etc. Although the exact pathogenesis of ACLF remains to be elucidated, alteration of host response to injury, infection, and unregulated inflammation play important roles. The predisposition, infection/inflammation, response, organ failure (PIRO) concept used for sepsis might be useful in describing the pathophysiology and clinical categories for ACLF. Treatment strategies are limited to organ support but better understanding of the pathophysiology is likely to lead to discovery of novel biomarkers and therapeutic strategies in the future.

Acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is an increasingly recognized distinct disease entity encompassing an acute deterioration of liver function in patients with chronic liver disease. Although there are no widely accepted diagnostic criteria for ACLF, the Asia.Pacific Association for the Study of the Liver (APASL) and the American Association for the Study of Liver Disease and the European Association for the Study of the Liver (AASLD/EASL) consensus definitions are commonly used. It is obvious that the APASL and the AASLD/EASL definitions are based on fundamentally different features. Two different definitions in two different parts of the world hamper the comparability of studies. Recently, the EASL-Chronic Liver Failure Consortium proposed new diagnostic criteria for ACLF based on analyses of patients with organ failure. There are areas of uncertainty in defining ACLF, such as heterogeneity of ACLF, ambiguity in qualifying underlying liver disease, argument for infection or sepsis as a precipitating event, etc. Although the exact pathogenesis of ACLF remains to be elucidated, alteration of host response to injury, infection, and unregulated inflammation play important roles. The predisposition, infection/inflammation, response, organ failure (PIRO) concept used for sepsis might be useful in describing the pathophysiology and clinical categories for ACLF. Treatment strategies are limited to organ support but better understanding of the pathophysiology is likely to lead to discovery of novel biomarkers and therapeutic strategies in the future.

Imbalance between circulating CD4+ regulatory T and conventional T lymphocytes in patients with HBV-related acute-on-chronic liver failure

BACKGROUND & AIMS

The important pathophysiological role of immune dysfunction, especially innate immune dysfunction in patients with acute-on-chronic liver failure (ACLF), has been investigated in recent years, but dysregulation of adaptive immunity remains poorly elucidated. The aim of this study was to (i) determine the CD3(+) T-lymphocyte count and the balance between CD4(+) regulatory T (Tregs) and conventional T cells (Tconv) in hepatitis B virus (HBV)-related ACLF patients; (ii) analyse the frequencies of Tregs subpopulations; and (iii) assess the suppressive potency of CD4(+) Tregs and each fraction.

METHODS

We enrolled 20 HBV-ACLF patients, 10 septic shock subjects, 20 chronic hepatitis B (CHB) patients and 20 healthy volunteers (HC). Based on flow cytometry, we performed the absolute counting of circulating T lymphocytes and phenotyping of CD4(+) Tregs and quantified the effects of Tregs and each subpopulation on Tconv proliferation by CFSE staining.

RESULTS

Compared with CHB patients and HC, we observed an equal reduction in peripheral T subsets in HBV-ACLF and septic shock subjects; the number of CD4(+) Tregs remained unchanged and the Tconv count declined, promoting elevation of the Treg-to-Tconv ratio. The frequencies of Treg-II and -III were elevated in HBV-ACLF. Functional studies showed that the suppressive capacity of Tregs was preserved in the HBV-ACLF group and Treg-II came first.

CONCLUSIONS

Similar to septic shock subjects, in HBV-ACLF patients there exists a reduction in CD4(+) T lymphocytes, predominantly CD4(+) Tconv, and the development of suppressive CD4(+) Tregs greatly prevails over Tconv, constituting important characteristics of adaptive immune dysfunction of HBV-ACLF.

Hepatitis E and Acute-on-Chronic Liver Failure

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis (AVH) globally. It causes large scale epidemics of AVH across the low- and middle income countries in Asia and Africa, and also causes sporadic cases of AVH in the same geographical region. AVH due to HEV is usually an acute, self-limiting illness, similar in clinical presentation to AVH caused by hepatitis A virus (HAV). When HEV causes AVH in patients of chronic liver disease it may worsen rapidly to a syndrome called acute-on-chronic liver failure (ACLF) leading to very high mortality. Acute deterioration of liver function in a patient with compensated chronic liver disease is the characteristic feature of ACLF. The typical disease course of patients with ACLF is the appearance of organ failure, which progresses to multi-organ failure and death. Many publications have reported HEV as one of the leading causes for ACLF from Asia and Africa, where HEV is endemic. The mortality rate of HEV-related ACLF (HEV-ACLF) ranges from 0% to 67% with a median being 34%. These patients require admission in the intensive care unit and they benefit from a team approach of clinicians with expertise in both hepatology and critical care. The goals of treatment are to prevent further deterioration in liver function, reverse precipitating factors, and support failing organs. Liver transplantation is required in selected patients to improve survival and quality of life. One preliminary report suggests that ribavirin may be an effective and safe drug for treatment of HEV-ACLF however this requires validation in large trials.

Hepatic and systemic hemodynamic derangements predict early mortality and recovery in patients with acute-on-chronic liver failure

BACKGROUND AND AIMS

Acute-on-chronic liver failure (ACLF) is a clinical entity where there is a potential for reversibility of hepatic dysfunction once the acute hepatic insult resolves. The portal and systemic hemodynamics in ACLF patients to study its relevance in determining the clinical outcomes was studied.

METHODS

Clinical, laboratory, portal, and systemic hemodynamic assessments were done at admission and after 3 months. Standard medical care was given to all the patients.

RESULTS

Fifty-seven patients with ACLF were enrolled, and they underwent baseline hepatic venous pressure gradient (HVPG) measurement. Twenty-six (46%) patients died during the 3-month follow-up. Presence of high HVPG and hepatic encephalopathy were found to be independent baseline predictors of mortality. Of the 31 surviving patients, 24 consented for a repeat HVPG. The baseline HVPG reduced from 16 (range 12-30) to 13 (range 6-21) mmHg; (P < 0.05). The reduction in HVPG correlated with clinical and biochemical recovery, and reduction in Child-Turcotte-Pugh score score (P < 0.05), while the aortic mean arterial pressure, cardiac index and systemic vascular resistance index improved significantly (< 0.05). Six (25%) patients developed upper gastrointestinal bleed; the median HVPG between bleeders and non-bleeders was not different possibly because of early onset of bleed (median 20 [15-45 days]).

CONCLUSIONS

Baseline HVPG is an independent predictor of mortality in ACLF patients. The portal and systemic circulatory anomalies regress substantially by 90 days and correlate with clinical recovery. However, in the initial phase, the raised portal pressure predisposes these patients to high risk of variceal bleeding.

Acute-on chronic liver failure

Acute-on-chronic liver failure (ACLF) is an increasingly recognised entity encompassing an acute deterioration of liver function in patients with cirrhosis, which is usually associated with a precipitating event and results in the failure of one or more organs and high short term mortality. Prospective data to define this is lacking but there is a large body of circumstantial evidence suggesting that this condition is a distinct clinical entity. From the pathophysiologic perspective, altered host response to injury and infection play important roles in its development. This review focuses upon the current understanding of this syndrome from the clinical, prognostic and pathophysiologic perspectives and indicates potential biomarkers and therapeutic targets for intervention.

Acute-on-chronic liver failure in chronic hepatitis B

Acute-on-chronic liver failure (ACLF) in chronic hepatitis B (CHB) is most commonly caused by acute severe exacerbation of CHB. The pathophysiology of ACLF in CHB is still poorly understood. Despite the identification of important predisposing factors and prognostic markers, ACLF in CHB remains a disease associated with high mortality. The majority of studies using nucleoside analog therapy did not show any significant improvement in survival, although larger prospective studies are needed. Liver transplantation is the definitive treatment for ACLF in CHB. The challenge ahead would be prognosticating cases with favorable or unfavorable outcomes in order to streamline patients for early transplantation or for medical therapy.

Acute-on-chronic liver failure: the heart and systemic hemodynamics

PURPOSE OF REVIEW

Circulatory abnormalities in cirrhosis include hyperdynamic circulation and cirrhotic cardiomyopathy. The extent of circulatory abnormalities is further exaggerated in acute-on-chronic liver failure (ACLF). The mechanism remains unclear and management also needs to be evaluated.

RECENT FINDINGS

The predominant mechanism of ACLF is thought to be a systemic inflammatory reaction. Cardiovascular-active factors such as tumor necrosis factor and nitric oxide are increased and cortisol is decreased; the former further dilates the vasculature and the latter decreases the sensitivity to vasoconstrictors. The exaggerated vasodilatation further decreases the cardiac afterload. However, no study has yet demonstrated the benefit of vasodilators/vasoconstrictors in the management of ACLF. Standard medical treatment in this setting is associated with high mortality. Patients treated with molecular adsorbent recirculating system (MARS) had improved serum levels of inflammatory mediators such as tumor necrosis factor alpha and interleukin-6, but this was not associated with improved survival. Liver transplantation eventually reverses the cardiovascular abnormalities.

SUMMARY

Circulatory abnormalities are exaggerated in ACLF. The predominant mechanism is a systemic inflammatory reaction. Modalities such as MARS improve serum markers of inflammation, but not survival. Liver transplantation is the definitive treatment of the cardiovascular abnormalities of ACLF.

Renal function and severity of bright liver. Relationship with insulin resistance, intrarenal resistive index, and glomerular filtration rate

AIMS

Relationships of renal function and liver disease are described in acute and chronic liver failure. The aim of the study is to investigate which relationship, if any, is present between severity of non-alcoholic fatty liver disease (NAFLD), assessed by bright liver score (BLS) versus mild-moderate renal insufficiency assessed by glomerular filtration rate (GFR) and by ultrasound intra-renal arterial resistive index (RRI). Moreover, which difference, if any, can be found in NAFLD patients with normal versus increased transaminases.

PATIENTS

The study enrolled 323 NAFLD and 176 non-NAFLD consecutive patients, comparable for age, gender distribution, GFR, and RRI referred to a university clinical day hospital after an ultrasound diagnosis of bright liver, for clinical-nutritional counselling. Personalized computerized mediterranean diet, physical activity increase, and smoking withdrawal integrated counselling were provided.

RESULTS

In NAFLD patients, homoeostasis model (HOMA) has a significant correlation with BLS. According to the severity of BLS, grade II-III versus grade I patients have significantly higher values of HOMA, body mass index (BMI), triglycerides, and longitudinal right liver length. By odds ratio, more severe BLS, increased HOMA, and transaminases are associated with lower GFR. Increased transaminases are associated with higher grades of BLS, HOMA, and BMI. By multiple linear regression waist-to-hip ratio, RRI, and BLS, as significant independent factors (p < 0.0001), explain significantly variance to GFR. This is not observed in normal control group, in which only RRI is a factor explaining GFR.

CONCLUSION

Greater RRI, abdominal obesity, and greater BLS account for a lower GFR in NAFLD patients suggesting the hypothesis that inter-related factors can be operating early in the natural history of obesity-related kidney and liver disease.

Predictors of outcome in acute-on-chronic liver failure in children

BACKGROUND AND AIMS

Acute-on-chronic liver failure (ACLF) is associated with a high mortality rate in the absence of liver transplantation. There is limited data on predictors of survival in ACLF in children. Therefore, we prospectively studied the predictors of outcome of ACLF in children.

METHODS

A prospective evaluation of 31 children in the age group of 1-16 years who fulfilled the criteria for ACLF according to Asian Pacific Association for the Study of the Liver (APASL) 2008 consensus was done. All consecutive children were evaluated for etiology, diagnosis and severity of ACLF. For grading of organ dysfunction, the sequential organ failure assessment (SOFA) score was calculated. SOFA constitutes the parameters of respiration, coagulation, cardiovascular system, central nervous system, and renal and liver functions. We evaluated possible correlation between outcomes and different variables.

RESULTS

Of the 31 children who fulfilled the criteria for ACLF, the common underlying chronic liver diseases (CLD) were autoimmune hepatitis (AIH) in 41.9% and Wilson disease in 41.9% of the patients. Superinfection with hepatitis A virus (HAV) (41.9%) was the most common etiology of acute deterioration. To find the best predictor for outcome, linear regression analysis was performed. Multivariate analysis revealed that the SOFA score and the International Normalized Ratio (INR) were predictors of survival. Six (19.4%) patients died. Causes of death were multiorgan failure in four and liver failure in two patients.

CONCLUSION

The mortality in ACLF is 19.4% and the causes of death were multiorgan failure and liver failure. The SOFA score and INR were predictors of outcome of ACLF in children.

Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific Association for the study of the liver (APASL)

The Asian Pacific Association for the Study of the Liver (APASL) set up a working party on acute-on-chronic liver failure (ACLF) in 2004, with a mandate to develop consensus guidelines on various aspects of ACLF relevant to disease patterns and clinical practice in the Asia-Pacific region. Experts predominantly from the Asia-Pacific region constituted this working party and were requested to identify different issues of ACLF and develop the consensus guidelines. A 2-day meeting of the working party was held on January 22-23, 2008, at New Delhi, India, to discuss and finalize the consensus statements. Only those statements that were unanimously approved by the experts were accepted. These statements were circulated to all the experts and subsequently presented at the Annual Conference of the APASL at Seoul, Korea, in March 2008. The consensus statements along with relevant background information are presented in this review.